Technical White Paper Refinement of Alternatives Fitzgerald & Halliday, Inc. URS Corporation AES Keville Enterprises, Inc. In association with: State Project 151-301 Fitzgerald & Halliday, Inc. URS Corporation AES Keville Enterprises, Inc. In association with: Prepared for: Prepared by: June 2007 Connecticut Department of Transportation State Project 151-301 Technical White Paper Refinement of Alternatives Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 1 1 Introduction ……………………………………………………………… …………………………………………. 4 1.1 Screening Analysis ……………………………………………………………… ………………………….. 4 2 Alternative Definitions ……………………………………………………………… ………………………….. 7 2.1 Conceptual Alternative 6 ……………………………………………………………… ………………….. 8 2.2 Conceptual Alternative 7 ……………………………………………………………… ………………….. 9 2.3 Conceptual Alternative 8 ……………………………………………………………… ………………… 10 2.4 Selection and Refinement of a Preferred Transportation Alternative …………………….. 11 3 Operations and Safety ……………………………………………………………… ………………………… 15 3.1 Traffic Volumes ……………………………………………………………… …………………………….. 15 3.2 Freeway and Ramp Analysis……………………………………………………………… …………… 15 3.2.1 Freeway Capacity Analysis ……………………………………………………………… ……… 17 3.2.2 Ramp Merge/Diverge Analysis ……………………………………………………………… …. 18 3.2.3 Weave Analysis ……………………………………………………………… ……………………… 21 3.3 Local Traffic Analysis ……………………………………………………………… …………………….. 24 3.4 Routing Analysis……………………………………………….. ………………………………………….. 26 3.5 Geometric Improvements ……………………………………………………………… ……………….. 38 3.5.1 Summary of Geometric Deficiencies …………………………………………………………. 40 4 Environmental Analysis ……………………………………………………………… ……………………… 41 4.1 Land Use and Neighborhoods………………………………………. ………………………………… 41 4.1.1 Existing Conditions ……………………………………………………………… …………………. 41 4.1.2 Land Use and Neighborhood Impacts ……………………………………………………….. 42 4.2 Business Activity and Major Employers ……………………………………………………………. 44 4.2.1 Existing Conditions ……………………………………………………………… …………………. 44 4.2.2 Impacts to Major Employers ……………………………………………………………… …….. 44 4.3 Visual/Aesthetic Resources……………………………………………………………… …………….. 45 4.3.1 Existing Conditions ……………………………………………………………… …………………. 45 4.3.2 Visual/Aesthetic Impacts ……………………………………………………………… …………. 46 4.4 Historic Resources ……………………………………………………………… ………………………… 46 4.4.1 Existing Conditions ……………………………………………………………… …………………. 46 4.4.2 Historic, Archeological, and Section 4(f) Resource Impacts………………………….. 48 4.5 Community and Institutional Resources ……………………………………………………………. 48 4.5.1 Existing Conditions ……………………………………………………………… …………………. 48 4.5.2 Community Facilities and Resources Impacts…………………………………………….. 49 4.6 Environmental Justice ……………………………………………………………… ……………………. 49 4.6.1 Existing Conditions ……………………………………………………………… …………………. 49 4.6.2 Impacts to Environmental Justice Populations ……………………………………………. 50 4.7 Surface Water and Groundwater……………………………………………………………… ……… 51 4.7.1 Existing Conditions ……………………………………………………………… …………………. 51 4.7.2 Impacts to Surface and Groundwater ………………………………………………………… 52 4.8 Floodplains ……………………………………………………………… …………………………………… 53 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 2 4.8.1 Existing Conditions ……………………………………………………………… …………………. 53 4.8.2 Impacts to Floodplains ……………………………………………………………… ……………. 53 4.9 Wetlands ……………………………………………………………… ……………………………………… 54 4.9.1 Existing Conditions ……………………………………………………………… …………………. 54 4.9.2 Impacts to Wetlands ……………………………………………………………… ……………….. 54 4.10 Endangered Species ……………………………………………………………… ……………………… 54 4.11 Hazardous Materials Risk Sites ……………………………………………………………… ………. 55 4.11.1 Existing Conditions ……………………………………………………………… …………………. 55 4.11.2 Impacts to Hazardous Materials Risk Sites ………………………………………………… 55 4.12 Farmlands ……………………………………………………………… ……………………………………. 55 4.12.1 Existing Conditions ……………………………………………………………… …………………. 55 4.12.2 Impacts to Prime Farmlands ……………………………………………………………… ……. 56 4.13 Air Quality ……………………………………………………………… …………………………………….. 56 4.13.1 Air Quality Attainment Status ……………………………………………………………… …… 56 4.13.2 Impacts to Air Quality ……………………………………………………………… ……………… 57 4.14 Noise ……………………………………………………………… ……………………………………………57 4.14.1 Existing Conditions ……………………………………………………………… …………………. 57 4.14.2 Impacts to Noise Sensitive Receptors ……………………………………………………….. 58 4.15 Summary Matrix ……………………………………………………………… ……………………………. 58 5 Cost and Constructability ……………………………………………………………… …………………… 60 5.1 Discussion of Conceptual Alternatives and Cost Estimates …………………………………. 60 5.1.1 Conceptual Alternative 6 ……………………………………………………………… …………. 60 5.1.2 Conceptual Alternative 7 ……………………………………………………………… …………. 60 5.1.3 Conceptual Alternative 8 ……………………………………………………………… …………. 61 5.1.4 Summary of Costs ……………………………………………………………… ………………….. 61 5.2 Constructability ……………………………………………………………… ……………………………… 62 5.2.1 Conceptual Alternative 6 ……………………………………………………………… …………. 63 5.2.2 Conceptual Alternative 7 ……………………………………………………………… …………. 64 5.2.3 Conceptual Alternative 8 ……………………………………………………………… …………. 64 6 Financial Analysis ……………………………………………………………… ………………………………. 66 6.1 Benefit-Cost Analysis ……………………………………………………………… …………………….. 66 6.1.1 Benefits ……………………………………………………………… ………………………………… 66 6.1.2 Costs ……………………………………………………………… ……………………………………. 66 6.2 Benefit Cost Ratio ……………………………………………………………… …………………………. 67 7 Visualization ……………………………………………………………… ………………………………………. 69 8 Summary ……………………………………………………………… ……………………………………………. 72 8.1 Capacity Analysis of Interchange System …………………………………………………………. 72 8.2 Routing Analysis……………………………………………….. ………………………………………….. 73 8.3 Geometric Improvements ……………………………………………………………… ……………….. 74 8.4 Local Road Impacts……………………………………………………………… ……………………….. 75 8.5 Environmental Impacts ……………………………………………………………… …………………… 76 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 3 8.6 Capital Cost Estimates ……………………………………………………………… …………………… 78 8.7 Benefit Cost Analysis ……………………………………………………………… …………………….. 78 8.8 Ranking of Conceptual Alternatives ……………………………………………………………… …. 79 8.8.1 Construction Cost ……………………………………………………………… …………………… 81 8.8.2 Life Cycle Cost ……………………………………………………………… ………………………. 82 8.8.3 Constructability ……………………………………………………………… ………………………. 82 8.8.4 Environmental Impact……………………………………………………………… ……………… 83 8.8.5 Safety/Meets Design Standards. ……………………………………………………………… . 83 8.8.6 Connectivity ……………………………………………………………… …………………………… 84 8.8.7 Economic Development ……………………………………………………………… ………….. 84 8.8.8 Intermodal Connections ……………………………………………………………… ………….. 85 8.8.9 Traffic Operations/Capacity Accommodation ……………………………………………… 85 8.9 Recommendation ……………………………………………………………… ………………………….. 85 9 References ……………………………………………………………… ……………………………………… …. 87 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 4 1 Introduction 1.1 Screening Analysis In Technical Memorandum #2, a sc reening analysis of the five preliminary improvement alternatives and a no-build alte rnative was undertaken using criteria developed by the study team and project stakeholders. Of thes e five preliminary alternatives, two included partial reconstruction of the interchan ge with the primary goals of reducing overall project cost and environmental impact. Based on the screening analysis, the five alternatives ranked from highest to lowest as follows: • Preliminary Alternative 5 – Full Build • Preliminary Alternative 2 – Safety and Operational Improvements • Preliminary Alternative 4 – Partia l Build (New I-84 Westbound Mainline) • Preliminary Alternative 3 – Partial Build (New I-84 Eastbound Mainline) • Preliminary Alternative 1 – TSM/TDM/Transit • No-build – Includes Maintenance of Existing Interchange Structure Only Based on the screening analysis and careful consideration of structural issues, it was recommended that the study not advance the Partial Build alternatives fo r further consideration . The primary reasons for not recommendi ng any alternative that would make use of some of the existing structure was that such an alternative would still require significant reconstruction of most, if not a ll, of the existing interchange and would not fully address the safety and operational deficienci es that the study identified as high priority. Given the substantial cost and compromised performance of the Partial Build alternatives, it was clear to the study team that such an al ternative would not be a viable long term solution and therefore, not appropriate for further study. This recommendation would also apply to an option for in-kind replacement of the existing I-84 structures over the Naugatuck River and existing rail yard, as well as the Route 8 structures which allow for access to and from I-84 and loca l connections. To replace the existing I-84 and Route 8 structures would require a complete replacement, including ramps and connecting roadways on a new location. The relocation of th ese structures to facilitate the movement of traffic during reconstruction would ultimately result in an overall effort and cost that would be comparable to that required for the new infrastruc ture associated with a full-build alternative. Results of Screening Analysis The process of developing the screening criteria and the relative weighting of each was a collaborative effort between ConnDOT, FHWA, COGCNV, City of Waterbury and consultant staff which resulted in the following list of screening criteria: Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 5 • Construction Cost • Life Cycle Cost • Constructability • Environmental Impact • Safety/Meets Design Standards • Connectivity • Economic Development • Intermodal Connections • Traffic Operations/Capacity Accommodation. Each of the five preliminary alternatives was assessed using the screening criteria. For the purposes of this Memorandum, the performance of th e Partial Build alternatives relative to each screening criterion is discussed below. Construction Cost – Preliminary construction cost estimates for the Partial Build alternatives proved to be 70- 90% of the cost of the Full Build alternative. Life Cycle Cost – Life cycle cost refers to the maintenance cost associated with each Preliminary Alternative over the 50-year pe riod beyond 2030. The Partial Build alternatives 3 and 4 were anticipated to have a higher life cy cle cost than a Full Build alternativ e due to the fact that part of the I-84 mainline would not be replaced and t hus require extensive future maintenance. Constructability – The Partial Build alternatives were given the lowest ranking in terms of constructability. The Partial Build alternatives involve maintaining portions of the existing I-84 mainline and constructing new mainline spans. These alternatives would pose significant challenges to construction since the existing system of piers are not capable of supporting new ramp connections. The existing viaduct is a no n-redundant structure, meaning a single failure, such as a fatigue crack in a weld, could cause the total collapse of at least a portion of the structure. Additionally, the pier s cannot be easily modified and are not oriented in a way that would allow proper geometric design of new ramps. Finally, these alte rnatives would require complex and costly traffic management program s to handle existing highway traffic while construction is ongoing. Environmental Impact – The Partial Build alternatives would impact the environment in roughly equal proportions to the Full Build alternative. Safety/Meets Design Standards – This goal is a measure of a roadway system’s ability to safely and efficiently accommodate traffic. The Par tial Build alternatives addressed fewer roadway geometric deficiencies (e.g. left hand ramp, clos ely spaced ramps, substandard radii, etc.) when compared to the Full Build Alternative. Connectivity – The Partial Build alternatives performed similarly to the Full Build alternative in terms of serving important destinati ons within the City of Waterbury. Economic Development – The Partial Build alternatives were not as highly rated in this category as the Full Build alternative, which was seen as supporting economic development by rebuilding Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 6 the I-84/Route 8 structure and its approaches resulting in significantly improved access and circulation. Intermodal Connections – The Partial Build alternatives performed similarly to the Full Build in terms of allowing for improved intermodal connections. Traffic Operations/Capacity Accommodation – For the Traffic Operations/Capacity Accommodation goal, freeway segments, weave ar eas and ramp junctions with LOS E and LOS F were identified as traffic operational deficienci es. The Partial Build alternatives are projected to include between 10 and 23 traffic operational deficiencies compared to 3 under the current Full Build alternative. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 7 2 Alternative Definitions Technical Memorandum #2 evaluated five Pre liminary Alternatives for the I-84/Route 8 Interchange area, which are ge nerally described as follows: Preliminary Alternative 1, TSM/TDM/Transit – This alternative was conceived as a “minimum build” concept that would maximize the operation of the existing transportation system without any roadway construction. Preliminary Alternative 2, Safety and Operational Improvements – This alternative would make minor improvements to the local roadway system to increase safety, and would involve minimal reconfiguration of the I-84/Route 8 infrastructure. Preliminary Alternatives 3 and 4, “Partial Bu ild” Additional Mainline Capacity Expansion – These two alternatives seek to address many of the deficiencies present in the existing corridor by rebuilding either the eastbound or westbound I-84 mainline. At the same time, they would maintain some of the existing mainline roadway structures in an attempt to minimize costs and environmental impacts. Preliminary Alternative 5, “Full Build” – This alternative would involve tota l reconstruction of the I-84 corridor with new eastbound and westbound ma inlines. The new structures that would carry both the eastbound and westbound mainlines w ould be constructed to run parallel to and south of the existing highway. The vertical stacking of the I-84 br idge over the Naugatuck River would be eliminated. The primary reasons for cons tructing the bridge in a parallel, rather than a stacked, configuration are as follows: • The overall profile would be lower in elevation resulting in aesthetic improvements; • Fewer design exceptions are required – i.e. left hand ramps, substandard grades, ramps spacing, etc. – which is a major issue with the curr ent interchange; • Maintenance and protection of traffic during construction is less complex, thus minimizing impacts to daily travel through the city; and • Construction methods are more conventional resulting in faster and more economical construction. The screening analysis conducted in Technical Memorandum #2 identified three transportation alternatives to be advanced to this phase of the project. To maintain a consistent numbering convention, the three alternativ es will be referred to as Conceptual Alternative 6, 7, and 8 throughout the remainder of this docum ent. These alternatives are: • Conceptual Alternative 6 – A combination of Preliminary Alternatives 1 and 2, which involves Transportation Demand Management/Transportation System Management/Transit and Safety Operation improvements. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 8 • Conceptual Alternative 7 – A derivative of Preliminary Alternative 5, which involves the full reconstruction of I-84 and Route 8 interchange with Route 8 following existing alignment. • Conceptual Alternative 8 – A derivative of Preliminary Alternative 5, which involves the full reconstruction of I-84 and Route 8 interchange with Route 8 realigned to the east side of the Naugatuck River. Preliminary Alternatives 3 and 4 were eliminat ed from further consideration due to reasons stated previously. The following simple illustra tion explains the relationship of the current Conceptual Alternatives to the Preliminary A lternatives identified in Technical Memorandum #2. Ultimately, a Preferred Altern ative will be developed as a final product of this study. It should be noted that the No Build condition, while not an alternative per se, will also be advanced as a possible outcome of the study. The No Build condi tion implies that nothing will be done to the existing interchange over the next 25 years; however, that is not the case. Significant rehabilitation work wi ll be necessary to maintain the existing structure in safe operating condition and the cost of those im provements is recognized in this study. The three Conceptual Alternatives are described in more detail below. 2.1 Conceptual Alternative 6 Conceptual Alternative 6 is a combination of Transportati on System Management (TSM), Transportation Demand Management (TDM), Transit and Safety improvements. This alternative looks at enhancing the efficiency and effectiveness of the existing transportation system by improving transit, modifying signal timing and improving signage within the study area. The safety and operational enhancements undertaken under this alternative would improve traffic operations as well as driver and pedestrian sa fety particularly on the local roadway system. 6 7 8 1 2 3 4 5 Preliminary Alternatives Conceptual Alternatives Preferred Alternative (TBD ) Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 9 Conceptual Alternative 6 woul d not involve major structural modifications on the highway system. Key features of Conceptual Alternative 6 are illustrated in Figure 2-1 and would include: • New local connections from: o Sunnyside Avenue to Field Street; o West Main Street to Bank Street; and, o Bank Street to South Main Street. • A new bus circulator route to run between Brass Mill Mall and Waterbury Hospital to compliment the existing bus system. • The modification of existing transit service to improve intermodal connections between bus and rail transit in the downtown area. Th is includes providing efficient connections from the proposed intermodal cente r (site of existing train station) to existing pulse points at the City Green. The ongoing study of the proposed transit center is being closely monitored and the recommendations from that study will be coordinated with the planning recommendations pr esented in this study. • Pedestrian and bicyclist facility improvements, particularly in the vicinity of the existing rail station, to enhance access to bo th rail and bus transit systems. • I-84 and Route 8 Signage/Way Finding improvements at the following locations to improve access to the highway system from downtown Waterbury: o City Green; o Intersection of Highland Avenue and Sunnyside Avenue; o Intersection of Mill Street and Baldwin Street; and, o Intersection of Bank Str eet and Meadow Street. • Signal timing and coordination improvements at the Hamilton Avenue/Washington Street/Silver Lane intersection, Union Street /I-84 Entrance Ramp intersection and Union Street/I-84 Exit Ramp/Brass Mill Mall Drive intersection to reduce congestion and delays on the Union Street corridor. • Signal timing improvements on West Main Street/Thomaston Avenue intersection, West Main Street/Willow Street intersection and Freight Street/Willow Street intersection. • The consolidation of the I-84 eastbound exit ramps to Meadow and South Main Streets. 2.2 Conceptual Alternative 7 Conceptual Alternative 7 is one of two Full Build alternatives that were derived from Preliminary Alternative 5 from th e previous phase of this study. Conceptual Alternative 7 would expand mainline capacity and enhance roadway safety by reducing turbulent traffic flows resulting from the mix of local and high-speed through traffic. U nder this alternative, frontage roads are used to collect and distribute local tr affic while the interstate mainline and associated high speed ramps are dedicated to longer distance through trips. Under this alternative, new I-84 and Route 8 mainlines would be constructed. The new I-84 eastbound and westbound mainlines would run parallel to each other and would be located south Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 10 of the current I-84 footprint. The new Route 8 ma inline would for the most part, remain within the existing footprint of Route 8. Key features of Conceptual Alternative 7 are illustrated in Figure 2-2 and would include: • New I-84 and Route 8 Mainlines. • The introduction of a frontage road off the I-84 westbound exit ramp at Interchange 22 to reduce congestion on the I-84 mainline, west of Interchange 22. • The consolidation and relocation of the existi ng I-84 ramps at Interchange 18 to the area west of Country Club Road. • The introduction of new entrance ramps from Field Street to I-84 westbound and Route 8 northbound and southbound. • The relocation of the Rout e 8 northbound exit ramp to I- 84 eastbound at Interchange 30 further south to eliminate weaving on the Route 8 northbound mainline. • New local connections from: o Sunnyside Avenue to Meadow Street; and, o West Main Street to South Main Street. 2.3 Conceptual Alternative 8 Conceptual Alternative 8 is the other Full-Build alternative being considered. This alternative expands mainline capacity and enhances safety by removing left-hand exit and entrance ramps and increasing spacing between ramps. In additi on, this alternative would minimize construction staging, shorten the duration of construction, an d maximize local access through the use of at- grade frontage roads. Under this alternative, new I-84 and Route 8 mainlines would be constructed. The new I-84 eastbound and westbound mainlines would run parallel to each other and would be located south of the current I-84 footprint. The new Rout e 8 northbound and southbound mainlines would run parallel to each other and would be lo cated east of the Naugatuck River. Key features of Conceptual Alternative 8 are illustrated in Figure 2-3 and would include: • New I-84 and Route 8 Mainlines. • Two new interchanges at Freight and West Main Streets. • The introduction of a frontage road off the I-84 westbound exit ramp at Interchange 22 to reduce congestion on the I-84 mainline, west of Interchange 22. • The consolidation and relocation of the existi ng I-84 ramps at Interchange 18 to the area west of Country Club Road. • The introduction of a new entrance ramp from Field Street to I-84 westbound • The relocation of Interchange 30 on Route 8 fr om the Washington Street area to Fifth Street. • The relocation of the Rout e 8 northbound exit ramp to I- 84 eastbound at Interchange 30 further south to eliminate weaving on the Route 8 northbound mainline. • New local connections from: Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 11 o Sunnyside Avenue to South Main Street; o West Main Street to Meadow Street area; o West Main Street to Washington Avenue; and, o Bank Street to Baldwin Street. • The conversion of South Leonard Street to a two-way street, south of Washington Avenue. 2.4 Selection and Refinement of a Pref erred Transportation Alternative The goal at this phase of the project is to ev aluate the three Conceptual Alternatives and ultimately select a Preferred Alternative to be eval uated in greater detail. It is envisioned that Conceptual Alternative 6 and one of the Full Build alternatives (Conceptual Alternative 7 or 8) would be advanced to the next phase of the project where they would be consolidated into a single Preferred Alternative. For this screening to be successful, careful consideration of the pros and cons of each of the Full Build alterna tives must be given so that the transportation alternative that moves forward in the study process has the great est potential for advancement, ultimately, to construction. As part of this effort, the projec t team held a series of meetings with the Connecticut Department of Transportation, the City of Waterbury, the C ouncil of Governments of the Central Naugatuck Valley (COGCNV) and the Waterbury Deve lopment Commission (WDC) to assess each Conceptual Alternative on the basis of their strengths and weaknesses. Key issues arising from the di scussions related to how each Conceptual Alternative would fit into the City of Waterbury Long Range Economic Development plan, the constructability of the alternatives, various property impacts, and im provements to the local roadway system. The comments and feedback obtained from the deliber ations proved to be a valuable guide in developing strategies to further refine the alternatives presen ted in this document. Some of the stakeholder comments are presented in the Appendi x, which is provided on CD at the back of this report. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 15 3 Operations and Safety A future (2030) traffic operations and safety evaluation of the three Conceptual Alternatives was undertaken. The evaluation of Conceptual Alterna tives involved capacity analysis of the highway system using methodologies in the Highway Cap acity Manual for estimating Level of Service (LOS) on the freeways and interchange ramps, local road impact analysis, and local road routing analysis. Safety was assessed in terms of th e number of geometric improvements under each alternative. The effect of ge ometric improvements in terms of reductions to accident rates is quantified in Chapter 6. 3.1 Traffic Volumes ConnDOT provided future year 2030 peak hour traffic volumes for use in the analysis of the three Conceptual Alternatives. These volumes were based on historical traffic growth data and projected regional growth within the study area. The traffic volumes for each alternative are provided electronically in CADD and PDF fo rmat on CD at the back of this report. 3.2 Freeway and Ramp Analysis A capacity analysis of the highway system under each Conceptual Alternative was conducted. A study of capacity is important in determining th e ability of a specific roadway, intersection, or freeway to accommodate traffic under various levels of service. “Level of Service” (LOS) is a qualitative measure describing the degree of traffic congestion and driver comfort. In general there are six levels of service describing flow conditions: Level of Service A , the highest LOS, describes a condition of free flow, with low volumes and unrestricted speeds. Level of Service B represents a stable traffic flow with operating speeds beginning to be restricted somewhat by traffic conditions. Level of Service C , which is normally utilized for design purposes, describes a stable condition of traffic operation. It entails moderately restri cted movements due to higher traffic volumes, but traffic conditions are not objectionable to motorists . Level of Service D reflects a condition of more restrictive movements for motorists and the influence of congestion becomes more noticeable. It is generally considered the lower end of “acceptable” service. Level of Service E is representative of the actual capacity of the roadway or intersection and involves delay to all motorists due to congestion. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 16 Level of Service F , the lowest LOS, is described as forced flow and is characterized by volumes greater than the theore tical roadway capacity. Complete congestion occurs, and in extreme cases, the traffic stream comes to a complete halt. This is considered an unacceptable traffic operating condition. Table 3-1 highlights the LOS criteria for freeway sections. The level of service criteria for freeway sections is based on maximum density defined in terms of passenger cars per mile per lane (pc/mi/lane). Table 3-1 LOS Criteria for Freeway Sections Level of Service Maximum Density (pc/mi/lane) A 11 B 18 C 26 D 35 E 45 F Greater than 45 Source : 2000 Highway Capacity Manual Table 3-2 highlights the LOS criteria for freeway-ra mp junctions. The level of service criteria for freeway-ramp junctions is based on maximum density defined in terms of passenger cars per mile per lane. Table 3-2 LOS Criteria for Freeway-Ramp Junctions Level of Service Maximum Density (pc/mi/lane) A 10 B 20 C 28 D 35 E Greater than 35 F Demand exceeds capacity Source : 2000 Highway Capacity Manual Table 3-3 highlights the LOS criteri a for freeway weaving sections. The level of service criteria for freeway weaving sections is based on maximu m density defined in terms of passenger cars per mile per lane. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 17 Table 3-3 LOS Criteria for Weaving Areas Level of Service Maximum Density (pc/mi/lane) A 10 B 20 C 28 D 35 E Less than or equal to 43 F Greater than 43 Source : 2000 Highway Capacity Manual 3.2.1 Freeway Capacity Analysis A capacity analysis was conducted on freeway se gments on both the I-84 and Route 8 mainlines under all three Conceptual Alternatives. For all intents and purposes, Alternative 6 is identical to the No Build scenario for the freeway operational analysis. The results of the analysis on I-84 and Route 8 are presented in Table 3-4 and Table 3-5 respectively. Table 3-4 Future (2030) Freeway Capacity Analysis Summary-I-84 Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 SECTION ALONG I-84 EB WB EB WB EB WB Between Int. 17 and Int. 18 F(F) F(F) C(D) C(C) C(D) C(C) Between Int. 18 and Int. 19 D(E) D(D) C(C) D(D) C(C) D(D) Between Int. 19 and Int. 20 F(F) D(D) B(C) D(D) D(D) D(D) Between Int. 20 and Int. 21 E(E) D(D) C(C) D(D) D(D) D(D) Between Int. 21 and Int. 22 E(E) F(F) C(C) D(D) D(D) D(D) Between Int. 22 and Int. 23 F(F) F(E) C(C) D(D) C(C) D(D) East of Int. 23 D(D) F(F) D(D) D(D) D(D) D(D) Note: X(X) Represents LOS for AM peak hour. PM peak hour levels of service shown in parenthesis. As illustrated in Table 3-4, most segments on the I-84 mainline would operate at LOS E or F under Conceptual Alternative 6 during the future (2030) A.M. and P.M. peak hour conditions. Under Conceptual Alternatives 7 and 8, it is anticipated that all segments would operate at LOS D or better under future (2030) peak hour conditions. As illustrated in Table 3-5 on the following page , most segments on the Route 8 mainline would operate at LOS E or F under Conceptual Alternat ive 6 during future (2030) peak hour conditions. Under Conceptual Alternatives 7 and 8, it is anti cipated that all Route 8 segments would operate at LOS D or better. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 18 Table 3-5 Future (2030) Freeway Capacity Analysis Summary – Route 8 Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 SECTION ALONG RTE 8 NB SB NB SB NB SB Between Int. 29 and Int. 30 D(E) C(C) B(C) D(D) B(C) D(D) Between Int. 30 and Int. 31 D(F) E(E) B(C) C(C) C(D) C(C) Between Int. 31 and Int. 32 C(D) B(B) B(C) C(C) C(D) C(C) Between Int. 32 and Int. 33 B(C) C(C) B(D) C(B) – B(B) Between Int. 33 and Int. 34 C(E) E(C) B(D) C(C) B(D) C(B) Between Int. 34 and Int. 35 C(F) E(D) B(D) B(D) D(C) D(C) Note: X(X) Represents LOS for AM peak hour. PM peak hour levels of service shown in parenthesis. 3.2.2 Ramp Merge/Diverge Analysis Table 3-6 and Table 3-7 present the ramp me rge/diverge analysis for the I-84 eastbound and westbound directions respectively while Table 3-8 a nd Table 3-9 represent the ramp analysis for the Route 8 northbound and southbound directions. Table 3-6 Future (2030) Ramp Analysis Sum mary – I-84 Eastbound Direction Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Interchange 18 Exit ramp to Chase Parkway F(F) C(C) C(C) Entrance ramp from Chase Parkway F(F) B(B) C(B) Interchange 19 Entrance ramp from Chase Parkway – – B(C) Exit ramp to Route 8 SB F(F) A(A) A(A) Exit ramp to Route 8 NB F(F) A(A) A(A) Entrance ramp from Highland Ave. F(F) C(C) – Exit Ramp to Bank Street Connector – B(B) C(C) Interchange 20-21 Entrance ramp from Route 8 SB F(F) C(C) C(C) Entrance ramp from Route 8 NB F(F) C(C) C(C) Interchange 22 Exit ramp to South Main Street F(F) – – Entrance Ramp from Baldwin Street – – C(C) Table continued on next page Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 19 Interchange 23 Exit ramp to Frontage Road F(F) B(C) C(D) Entrance ramp from Hamilton Ave. C(D) C(C) C(D) Note: X(X) Represents LOS for AM peak hour. PM peak hour levels of service shown in parenthesis. Table 3-7 Future (2030) Ramp Analysis Summary – I-84 Westbound Direction Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Interchange 18 Exit ramp to West Main St./Highland Ave. F(F) – – Entrance ramp from Chase Pkwy. F(F) B(B) B(B) Interchange 19 Entrance ramp from Route 8 SB F(F) D(D) D(D) Entrance ramp from Route 8 NB F(D) D(D) D(D) Exit ramp to West Main St./Highland Ave – A(A) A(A) Interchange 20 Exit ramp to Route 8 SB F(F) B(B) C(C) Exit ramp to Route 8 NB D(F) B(B) C(C) Entrance Ramp from Field St. – D(D) D(D) Interchange 21 Exit ramp to Meadow St. F(F) – – Entrance ramp from Bank St. (Left) F(F) – – Entrance ramp from Bank St. (Right) F(F) – – Interchange 22 Exit ramp to Union St. F(D) C(C) C(C) Entrance ramp from Union St. F(F) B(B) B(B) Interchange 23 Exit ramp to Hamilton Ave. F(F) C(C) C(C) Note: X(X) Represents LOS for AM peak hour. PM peak hour levels of service shown in parenthesis. With the exception of the I-84 eastbound entrance ramp from Hamilton Avenue, all I-84 ramp merges and diverges within the study area are an ticipated to operate at LOS F during either the future (2030) A.M. or P.M. peak hour conditions for Conceptual Alternative 6. Under Conceptual Alternatives 7 and 8, all ramps are anticipated to operate at LOS D or better. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 20 Table 3-8 Future (2030) Ramp Analysis Summary – Route 8 Northbound Direction Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Interchange 30 Exit ramp to South Leonard Street B(C) B(C) B(C) Entrance ramp from South Leonard Street C(D) B(B) C(D) Interchange 31 Exit ramp to I-84 EB C(D) B(C) C(D) Interchange 32 Exit ramp to Riverside St. B(C) B(C) – Interchange 33 Exit ramp to I-84 WB B(C) B(C) B(C) Entrance ramp from I-84 EB B(D) B(D) – Entrance ramp from Riverside St. D(F) – – Entrance ramp from I-84 WB C(F) A(A) A(A) Interchange 34 Entrance ramp from W. Main Street D(F) B(C) A(A) Note: X(X) Represents LOS for AM peak hour. PM peak hour levels of service shown in parenthesis. Table 3-9 Future (2030) Ramp Analysis Summary – Route 8 Southbound Direction Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Interchange 30 Exit ramp to Charles Street D(D) D(D) D(D) Entrance ramp from Charles Street D(D) D(D) D(D) Interchange 31 Entrance ramp from I-84 WB D(D) D(D) D(D) Entrance ramp from I-84 EB C(B) C(B) D(D) Entrance ramp from Riverside B(B) B(B) – Exit ramp to I-84 EB F(C) B(B) – Interchange 32 Exit ramp to Riverside St. F(E) – – Interchange 33 Entrance ramp from West Main Street – – B(B) Exit ramp to I-84 WB F(C) D(B) – Exit ramp to Freight Street – – B(B) Entrance ramp from Freight Street – – C(D) Table continued on next page Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 21 Interchange 34 Exit ramp to W. Main Street C(B) D(C) C(B) Note: X(X) Represents LOS for AM peak hour. PM peak hour levels of service shown in parenthesis. For Route 8, six (6) ramp merges/diverges are antic ipated to operate at either LOS E or F during either the future (2030) AM or PM peak hour conditions under C onceptual Alternative 6. Under Conceptual Alternatives 7 and 8, all ramps are an ticipated to operate at LOS D or better during peak periods. 3.2.3 Weave Analysis A weave analysis is necessary on freeway segmen ts where an entrance ramp is directly followed by an exit ramp in close proximity. A number of weave segments were identified u nder all three Conceptual Alternatives based on freeway segment lane continuity and distance be tween entrance-exit ramp segments. Conceptual Alternative 6 recorded the highest number of weaves with seven weave segments; Conceptual Alternative 7 recorded five weav e segments while Conceptual Alternative 8 recorded six weave segments. The weave segments under each alternative are shown in Table 3-10. Table 3-10 I-84 and Route 8 Weave Segments Alternative Weave Segment Conceptual Alternative 6 I-84 Eastbound from • Chase Parkway to Route 8 SB • Route 8 NB to South Main Street I-84 Westbound from • Bank Street to Route 8 NB • Bank Street to Route 8 SB • Route 8 SB to Highland Ave Route 8 Northbound from • West Main Street to Watertown Ave. Route 8 Southbound from • Watertown Ave to West Main Street Table continued on next page Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 22 Conceptual Alternative 7 I-84 Eastbound from • Chase Parkway and Route 8 SB • Route 8 NB to Frontage Road I-84 Westbound from • Hamilton Avenue and Route 8 NB/SB • Field Street to Highland Ave Route 8 Southbound from • I-84 EB/WB to Interchange 30 Exit Conceptual Alternative 8 I-84 Eastbound from • Chase Parkway and Route 8 SB • Route 8 NB to Frontage Road I-84 Westbound from • Hamilton Avenue to Route 8 NB/SB Route 8 Northbound from • Washington Avenue to I-84 EB Route 8 Southbound from • West Main to I-84 WB • I-84 EB/WB to Interchange 30 Exit The weave segments were analyzed using the Highway Capacity Software (HCS). The results of the weaving analysis are summarized in Table 3-11. Table 3-11 Future (2030) Weave Analysis Summary – I-84 and Route 8 Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 SECTION BETWEEN AM PM AM PM AM PM I-84 Eastbound Direction Chase Parkway and Route 8 SB E F D D D D Route 8 NB to South Main Street F F – – – – Route 8 NB to Frontage Road – – D D C D Westbound Direction Hamilton Avenue to Route 8 NB/SB – – D E D E Bank Street to Route 8 NB E F – – – – Bank Street to Route 8 SB F F – – – – Field Street to Highland Ave – – C C – – Route 8 Southbound to Highland Ave F F – – – – Table continued on next page Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 23 Route 8 Northbound Direction West Main Street to Watertown Ave. D F – – – – Washington Avenue to I-84 EB – – – – D E Southbound Direction Watertown Ave to West Main Street F E – – – – West Main to I-84 WB – – – – C E I-84 EB/WB to Interchange 30 Exit – – D D E E As Table 3-11 indicates, almost all weave segmen ts would operate at LOS E or F during either the future (2030) A.M. or P.M. peak hour conditions under Conceptual Alternative 6. Under Conceptual Alternative 7, it is anticipated that the I-84 westbound weave segment from the Interchange 22 entrance ramp near Hamilton Avenue to the Route 8 northbound/southbound exit ramp would operate at LOS E during future (2030) P.M. peak hour conditions. The current spacing of this weave segment is 2,100 feet. The level of service for this segment can be improved by increasing the spacing of this segmen t to more than 2,500 feet. A spacing of more than 2,500 feet between en trance and exit ramps is not considered a weave section. Based on a review of Conceptual Alternative 7, the Exit 22 entrance ramp can be pulled back to eliminate the weave. Under Conceptual Alternative 8, four (4) weave segments are anticipated to operate at LOS E during future (2030) P.M. peak hou r condition. These segments are: • The I-84 westbound segment from the Interchange 22 entrance ramp near Hamilton Avenue to the Route 8 northbound/southbound exit ramp at Interchange 20; • The Route 8 northbound segment from th e Interchange 30 entrance ramp near Washington Avenue to the I-84 east bound exit ramp at Interchange 31; • The Route 8 southbound segment from the Interc hange 33 entrance ramp near West Main Street to the I-84 westbound exit ramp; and • The Route 8 southbound segment from the I-84 eastbound/westbound entrance ramp to the Fifth Street exit ramp at Interchange 30. The level of service at the four weave segmen ts could be improved by providing additional mainline lanes and increasing ramp spacing. Similar to Conceptual Alternative 7, the ramp spacing between the Interchange 22 entrance ramp and the Route 8 northbound/southbound exit ramp at Interchange 20 can be increased by pulling back the Interchange 22 entrance ramp. The curre nt spacing of this weave segment is 2,450 feet. Increasing the ramp spacing by 50 feet or more would eliminate the weave section. The weave section between the Route 8 nor thbound Interchange 30 entrance ramp and the Interchange 31 exit ramp (to I-84 eastbound) can be eliminated by braiding the entrance and exit ramps. Alternatively, th e weave segment should be four lanes wide. This can be achieved by providing a two lane entrance ramp from Wash ington Avenue (Interchange 30) and a two-lane exit ramp to I-84 eastbound (Interchange 31). Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 24 The Route 8 southbound weave segment from the In terchange 33 entrance ramp near West Main Street to the I-84 westbound exit ramp is approxima tely 700 feet. This creates a problem with the weave section. The solution may be to eliminate the weave section. The weave section on Route 8 southbound betw een the I-84 eastbound/westbound entrance ramp to the Fifth Street exit ramp at Interchange 30 can be eliminated by braiding the entrance and exit ramps. Alternatively, th e weave segment should be four lanes wide. This can be achieved by providing a two lane entrance ramp from I-84 (Interchange 30) and a two-lane exit ramp at Interchange 31. Additional analysis and refinements, such as those mentioned above, will be made to the Preferred Alternative in the s ubsequent phase of this study. 3.3 Local Traffic Analysis Although a detailed assignment of local road traffi c was not performed at this stage of the study, a qualitative review of the new local roadway sy stem under the three Conceptual Alternatives was conducted. The aim of this review was to a ssess the relative impact the new roads would have on the local roadway system. Intersections that are expected to experience a reduction in traffic volume are seen as positively impacted wh ile those that are expected to experience an increase in traffic volume will be more closely an alyzed so that improvements can be made, if necessary, to maintain safe and efficient operation. For the purposes of this study it should be noted that only ex isting intersections were analyzed. It was not necessary to analyze the new intersections created as a result of the new local connections since these intersections would be designed to accommodate the forecasted traffic demand. Additionally, this analysis is not base d on a detailed assignment of traffic along the local street network. It is based a professional judgment a nd for comparative purposes only. Once a Preferred Alternative is selected, detailed traffic assignment will be performed and LOS calculated for the local street system. Table 3-12 lists the impacted inte rsections in the study area. The appendix CD at the back of th is report provides more information. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 25 Table 3-12 Existing Intersections with Anticipa ted Net Increase/Decrease in Traffic Intersection Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 West Main Street/Riverside Street NB 5 5 West Main Street/Riverside Street SB 5 5 West Main Street/Meadow Street 5 5 ; Freight Street/Riverside Street SB 5 5 Freight Street/Meadow Street 5 5 ; Meadow Street/Grand Street 5 5 Grand Street/Field Street ; 5 5 Grand Street/Bank Street 5 5 Grand Street/South Main Street 5 5 Union Street/South Elm Street 5 5 Union Street/Mill Street 5 5 Union Street/Brass Mill Mall 5 5 Bank Street/West Liberty Street 5 5 5 Bank Street/Riverside Street 5 5 South Leonard Street/Bank Street 5 5 Chase Parkway/Sunnyside Avenue ; ; Sunnyside Avenue/Draher Street ; ; ; Sunnyside Avenue/Highland Avenue ; ; ; Legend 5 Decrease in intersection volume ; Increase in intersection volume For each alternative, the number of existing inte rsections that would experience a net increase or decrease in traffic volume as well as the number of existing intersections that would be improved to accommodate the forecasted traffic demand was ta llied. These results are summarized in Table 3-13. It is clear from Table 3-13 that for each alternative, there would be more intersections experiencing a net decrease in traffic volume th an an increase. Of the three alternatives, Conceptual Alternative 7 would result in the most improvements to existing local intersections; however, Alternative 8 will have 14 new intersections that will be constructed to operate at acceptable Levels of Service. It is important to note that a decrease in traffic volume does not necessarily mean that the intersection will operate at acceptable LOS. It is certain that any new intersection will be built to handle the traffic volume forecas ted to use it. For this reason, it is expected that Alternative 8 will most eff ectively improve local street operations. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 26 Table 3-13 Impact of Local Roadway Improvements Number of Existing Intersections anticipated to Increase in Volume Decrease in Volume Upgraded or new intersections Conceptual Alternative 6 4 9 7 Conceptual Alternative 7 2 15 5 Conceptual Alternative 8 5 7 14 3.4 Routing Analysis One of the key issues considered in this st udy was how each alternative would provide access to the City of Waterbury downtown area in a dir ect and timely manner. A routing analysis was undertaken to address the highway access and egress routes to five cardinal locations in the downtown area. These locations are: • Waterbury Hospital; • St. Mary’s Hospital; • Proposed intermodal transportation center; • Public garages; and • Government Center. This analysis involved identifying the most logical travel path to these five locations based on directness and convenience of the travel route. Figure 3-1 through Figure 3-5 illustrate the most likely travel paths to the various cardinal locations under Conceptu al Alternative 7, while Figure 3-6 through Figure 3-10 present the most likely travel paths under Conceptual Alternative 8. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 37 The travel paths developed under Conceptual Alternat ives 6, 7 and 8 were compared to the travel paths currently used by motorists to assess any routing improvements in terms of directness of the route and convenience of access. The results of the analysis are summarized in Table 3-14. Table 3-14 Summary of Routing Analysis Origin Destination Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 I-84 EB Waterbury Hospital    St Mary’s Hospital    Government Center    Transportation Center    Parking Garages    I-84 WB Waterbury Hospital   5 St Mary’s Hospital    Government Center    Transportation Center    Parking Garages    Route 8 NB Waterbury Hospital    St Mary’s Hospital    Government Center    Transportation Center    Parking Garages    Route 8 SB Waterbury Hospital    St Mary’s Hospital   5 Government Center   5 Transportation Center   5 Parking Garages   5 Legend 5 Improved Routing  No Routing Improvements Since Conceptual Alternative 6 would not invol ve any major modifications to the highway system, there would be no routing improvements with respect to the cardinal locations under this alternative. Under Conceptual Alternative 7, it is anticipated that the new travel routes would not offer much improvement in terms of directness of path. It is, however; anticipated that there would be five routing improvements under Conceptual Alternative 8. These improvements are discussed below. I-84 Westbound to Waterbury Hospital Most motorists currently traveling to Waterbur y Hospital from I-84 would either use the Field Street exit on I-84 or the Route 8 northbound exit ra mp at Interchange 35 to get to the Hospital. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 38 The new West Main Street exit ramp provided under Conceptual Alternative 8 would provide a more direct route to Waterbury Hospital than the routes currently used by motorists. Route 8 SB to St Mary’s Hospital, Governm ent Center, Transportation Center and Parking Garages Most motorists currently traveling from Route 8 southbound would use the West Main Street exit at Interchange 34 to get to the above locati ons. The new southbound Freight Street exit ramp provided under Conceptual Alte rnative 8 would provide a more direct route to the above locations than the route currently used by motorists. 3.5 Geometric Improvements A number of geometric deficiencies were identified in the existing conditions phase of this study based on stipulated guidelines from “A policy on Geometric Design and Highways and Streets” by the American Association of State Highway and Transportation Officials (AASHTO)-2001 edition. These deficiencies were highlighted in Chapter 6 of Technical Memorandum # 1 and include: • Left hand ramps; • Steep grades; • Substandard acceleration a nd deceleration lengths; • Substandard ramp spacing; • Substandard curve radius; and • Substandard ramp superelevation As stated earlier in this chapter, traffic safety under the three Conceptual Alternatives was assessed based on each alternative’s ability to imp rove geometric deficiencies identified in the existing conditions phase of this study. Since Conceptual Alternative 6 involves only minimal improvements to the highway system, it would not be able to address most of the geometric issues identified. On the other hand, Concep tual Alternatives 7 and 8, being Full Build alternatives, would be able to address a majority of the geometric deficiencies. Left hand ramps There are currently eight (8) left hand ramps w ithin the study area. Conceptual Alternative 6 does not involve any structural improvements on the highway system; therefore, there would be no improvements relative to left hand ramps under this alternative. Under Conceptual Alternatives 7 and 8, seven (7) left hand ramps would be eliminated. The exception would be the entrance ramp from I-84 eas tbound to Route 8 northbound. Substandard Grades Three (3) ramps with substandard grades were identified under the existing condition. None of the steep grades would be improved under C onceptual Alternative 6. Under Conceptual Alternatives 7 and 8, all substa ndard grades would be improved. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 39 Substandard Acceleration and Deceleration Lengths There are currently six (6) substandard ramp acceleration lengths and three (3) substandard deceleration lengths on the highway system. None of these substandard acceleration and deceleration lengths would be improved under C onceptual Alternative 6. Under Conceptual Alternatives 7 and 8, all subs tandard acceleration and decelera tion lengths would be improved. Substandard Ramp Spacing Under the existing interchange configuration, ther e are twenty-one (21) segments with ramp spacing deficiencies within the study area. Under Conceptual Alternative 6, the ramp spacing deficiency between Meadow Street exit ramp and South Main Street exit ramp on I-84 eastbound is the only segment that would be improved due to the consolidation of the Meadow Street/South Main Street ramps. Most of the substandard ramp spacing defici encies would be improved under Conceptual Alternative 7 and Conceptual Alternative 8. Under Conceptual Alternative 7, there would be five (5) segments with substandard ramp spacing. These segments are: • The I-84 eastbound segment from the Route 8 northbound entrance ramp to the Interchange 23 exit ramp (Frontage Road); • The Route 8 northbound segment from the I-84 westbound entrance ramp to the entrance ramp from West Main Street; • The Route 8 southbound segment from the I-84 westbound exit ramp to the I-84 eastbound exit ramp; • The Route 8 southbound segment from the I- 84 eastbound exit ramp to the entrance ramp from West Main Street; and • The Route 8 southbound segment from the I-84 westbound entrance ramp to the Interchange 30 exit ramp. Under Conceptual Alternative 8, th ere would be six (6) segments with substandard ramp spacing. These segments are: • The I-84 eastbound segment from the Chase Parkway entrance ramp to the Interchange 19 exit ramp; • The I-84 eastbound segment from the Route 8 northbound entrance ramp to the Interchange 23 exit ramp (Frontage Road); • The Route 8 northbound segment from the Inte rchange 30 entrance ramp to the exit ramp to I-84 eastbound; • The Route 8 northbound segment from the I-84 eastbound exit ramp to the I-84 westbound exit ramp; • The Route 8 southbound segment from the West Main Street entrance ramp to the I- 84 westbound exit ramp; and • The Route 8 southbound segment from the I- 84 entrance ramp to the Interchange 30 exit ramp. Under both Conceptual Alternatives 7 and 8, it is expected that more detailed engineering design will identify solutions to address the remaining substandard spacing issues. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 40 Substandard Curve Radius Currently the I-84 westbound exit ramp at Intercha nge 18 is the only ramp with a substandard curve radius. Under Conceptual Alternative 6, the curve radius on this r amp would not be improved. Under Conceptual Alternatives 7 and 8, the new I-84 eastbound entrance and exit ramps at Chase Parkway would not meet AASHTO curve radius design standards based on a 25 MPH design speed. This tight ramp geometry is a result of intentional avoidance of property impacts in this area. Lowering the design sp eed may result in achieving AASHTO standards. Substandard Ramp Superelevation Under Conceptual Alternative 6, there are two ramps with substandard superelevation rates. These ramps are: • The I-84 westbound exit ramp to Route 8 southbound at Interchange 20; and • The Route 8 northbound exit ramp to I-84 eastbound at Interchange 31. Under Conceptual Alternatives 7 and 8, th ere would be no ramps with substandard superelevation rates. 3.5.1 Summary of Geometric Deficiencies The number of geometric deficiencies under each of the three alternatives was tallied. Table 3-15 presents a summary of geometric deficiencies for each alternative. As the table indicates, Conceptual Alternative 7 would have the least number of geomet ric deficiencies with eight deficiencies followed closely by Conceptual Alternative 8 with nine deficiencies. Table 3-15 Summary of Geometric Deficiencies Geometric Deficiency Number of Deficiencies Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Left-hand Ramps 8 1 1 Substandard Grade 3 0 0 Substandard Acceleration Length 6 0 0 Substandard Deceleration Length 3 0 0 Substandard Ramp Spacing 21 5 6 Substandard Curve Radius 1 2 2 Substandard Superelevation 2 0 0 Total 44 8 9 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 41 4 Environmental Analysis The Interstate 84 (I-84) and Route 8 Interchange st udy area is situated entirely within the City of Waterbury and is generally bounded on the east a nd west by I-84 Interchanges 18 and 23 and to the north and south by Route 8 Interchanges 35 and 30 . The study area extends to a distance of approximately 1000 feet from either side of th e I-84 and Route 8 highways. The transportation network, in addition to Interstate 84 and Route 8, includes a complex system of local roads, a rail line that carries passengers (Metro-North), and freight service north and south of Waterbury. An important water feature in the study area is the Na ugatuck River, which runs north-south, parallel to Route 8. A multi-use trail has been planned with an alignment that parallels this river on the east. The following is a screening level assessment of the potential impacts of three proposed Interstate 84/Route 8 Interchange physical improvement alternatives on environmental resources in the study area. The overall focus of the st udy is to improve mobility through the I-84/Route 8 Interchange, including access to downtown Waterbury via local road enhancements and Transportation Demand Management/Transportation System Management. Environmental impacts are described in the study area from west to east and north to south where applicable. The analysis process for the environmental screening involved the overlay of concept alternatives on mapped resources . This task was completed primarily for the purposes of identifying potential alternative fatal flaws and to gain a planning-level view of potential issues and concerns associated with the alternative configurations. A detail ed impact analysis is neither prudent nor possible at this stage of project development. An in-d epth analysis will be conducted for compliance with National Environmental Policy Act (NEPA) and Connecticut Environmental Policy Act (CEPA) requirements as a preferred alternative is advanced into preliminary design. Further refinements of a selected preferred alte rnative would be developed with the intent to minimize potential impacts id entified within this study. 4.1 Land Use and Neighborhoods 4.1.1 Existing Conditions Documentary information on land use was obtaine d primarily from the Council of Governments of the Central Naugatuck Valley (COGCNV). Limite d visual inspections were also conducted. Land use in the study area is a reflection of the historic growth and settlement patterns of Waterbury that were driven by the industrial de velopment of the Naugatuck River Valley in the early nineteenth century. Since World War II, the region’s economy has diversified and its residents have become more widely dispersed throughout nearby suburbs. Predominant land uses in the study area are curren tly a mix of uses, which is common to most urban areas. Residential land uses in the immediate vicinity of the I-84/Route 8 Interchange are concentrated southwest and northwest of th e interchange. Industrial land uses occur predominantly in the immediate vicinity of the I-84 and Route 8 Interchange to the east, in the Freight Street area, and South Ma in Street corridor. Commercial land uses occur farther from the Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 42 interchange, and include downtown Waterbury to the northeast of the interchange. They generally occur to the northeast and southeast, along the West Main Street and East Main Street corridors. Some recreational (parks) and institutional (schools and City government) land uses are scattered within the area as well. There are twelve (12) neighborhoo ds in the study area designated as such for planning purposes by the City of Waterbury. They generally include a diverse mix of land uses such as residential, retail, and small industrial sites. Those that ar e mostly residential with some neighborhood scale commercial activity include the Boulevard, Bunker Hill, Country Club, Town Plot, Washington Hill, and West End neighborhoods. 4.1.2 Land Use and Neighborhood Impacts Potential land use impacts were assessed by overl aying each of the three Conceptual Alternative design plans onto existing land use mapping in order to identify locations where property acquisitions, impacts to land use patterns, or alterations to land access may occur. Neighborhood cohesion impacts were considered to occur in th ose instances where an alternative creates a new physical barrier to travel either within an established neighborhood or between a designated neighborhood and a known community facility or key resource. Table 4-1 summarizes the potential property acquisitions that may be re quired. The potential land use and neighborhood impacts are described in more detail below. Table 4-1 Potential Property Acquisitions Partial Property Acquisition Full Property Acquisition Conceptual Alternative 6 16 6 Conceptual Alternative 7 63 27 Conceptual Alternative 8 67 41 Conceptual Alternative 6 • Thomaston Avenue extension; West Main to Freight Street – two full industrial property takes; • New Connector Road – West Main to Bank St reet – three full industrial property takes, one full commercial property take, and three partial or strip takings from industrial properties; • New roundabout on Bank Street – four partial commercial property takes; • New connector road to South Main Street in the vicinity of the Exit 20 off-ramp westbound – two full commercial property takes and four partial takes; three from commercial properties, and one of which appears to be an apartment complex; and Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 43 • New connector road from Riverside to Union Street – three partial commercial property takes. The new local roads will enhance access in the vicinity of the downtown and to the industrial area east of the intercha nge. However, the industrial land ac quisitions may disrupt the existing pattern of land use in this area and new access ma y encourage changes in use. There will be no adverse impacts to neighborhood cohesi on from Conceptual Alternative 6. Conceptual Alternative 7 • All of the impacts anticipated with Conceptual Alternative 6 with the following additions and modifications; • Exit 18 eastbound ramps – two partial institu tional and three full residential takes; • Exit 18 westbound ramps and local road realignment – three partial residential takes, one partial industrial take, and two full commercial takes; • Exit 19 eastbound off-ramp and Chase Parkway north – one partial commercial take and one partial recreational property take; • Exit 19 eastbound on-ramp – three partial commercial takes; • New connector road Bank Street to South Main Street – six partial commercial takes • Bank Street realignment – tw o partial commercial takes; • No impact to properties at the intersection of South Main Street and South Elm Street; • Exit 21 entrance ramp (may be elevated) – one commercial and one industrial property partial take; • Exit 23 new ramps – partial take of some vacant land which is part of a cemetery; • Exit 32 entrance ramp – three partial residential takes; • Thomaston Avenue extension West Main to Ba nk Street – four full industrial takes and five partial industrial takes; • New connector road Bank Street to South Main Street – eight full commercial property takes ; • Sunnyside Avenue improvements to Meadow Street – one full commercial take; • New frontage road along the south edge of I-84/ Exit 21 eastbound on-ramp – two partial commercial property takes; • Charles Street and Exit 30 on Route 8 – three partial residential takes, one partial multi- family complex acquisition, one full industrial take and 10 full residential takes; and • Leonard Street – 11 partial commercial property acquisitions. Impacts to land use patterns would be somewhat similar to those described for Conceptual Alternative 6, except that there w ould be no impact to the Maloney Interdistrict Magnet School. Enhanced access to the Country Club and Town Plot neighborhoods may also be achieved under this alternative. However, a drawback is that th ere may be some residential property takes in the Town Plot neighborhood as well as at the periphery of the Country Club neighborhood. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 44 Conceptual Alternative 8 • All of the impacts anticipated with Conceptual Alternative 7 at exits 18, 19, 23 and connector/frontage roads with the follow ing other additions and modifications; • Thomaston Avenue Extension West Main to Fr eight Street – two full industrial takes; • New connector road, Freight Street to realigned Sunnyside Avenue – one partial industrial take; • Meadow Street intersection with Sunnysid e Avenue – two full commercial takes; • Exit 21 new connector road – two full commercial takes; • South Elm Street reconfigurat ion at exit 21 entrance ramp – one full school property take (Maloney Inter-district Magnet Sc hool), one full residential take, and one full industrial take; and • South Elm Street cul-de-sac – two pa rtial commercial property takes. Impacts to land use patterns would be similar to those described for Conceptual Alternative 6. Neighborhood impacts would be similar to those described above for Conceptual Alternative 7 except that Conceptual Alterna tive 8 would also involve taking a school (Maloney Interdistrict Magnet School), which is considered to be a significant adverse impact to neighborhood cohesion. 4.2 Business Activity and Major Employers 4.2.1 Existing Conditions There is a high concentration of businesses with 50 or more employees in the study area, particularly near downtown Water bury. The clustering of these businesses in the vicinity of I-84 and Route 8 is indicative of the important relati onship between the transportation infrastructure and employment centers. The larges t employers in the study area include: • Brass Mill Center and Commons; • City of Waterbury; • Connecticut Light & Power; • Home Depot; • Jarjura’s Fruit ; • MacDermid, Inc.; • Sports Authority; • St. Mary’s Hospital; • Waterbury Hospital; and • Webster Bank. 4.2.2 Impacts to Major Employers The potential commercial and indu strial property takes described in Section 2 above would also result in some potential for relocation of employment in the study area. Major employers with 50 or more employees that may need to be relo cated under each alternative are estimated below. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 45 Conceptual Alternative 6 This alternative could result in the relocation of three major employers in the industrial area along the northeast qu adrant of the interchange between Frei ght Street and West Main Street. As there is a substantive amount of warehousing ac tivity in this area, the remaining employer dislocations may have less of an adverse employmen t impact than that typically associated with an industrial property acquisition. Conversely, the new connector road to industrial land may enhance access and encourage redevelopment and infill of underutilized parcels. Conceptual Alternative 7 This alternative would have impacts similar to th ose described for Conceptual Alternative 6 with one additional major employer relocation with an added industrial property take in the industri al area between Freight and West Ma in Street. In addition, this alternative could require the acquisition of two large retail employers in the area immediately east of Bank Street at the Exit 21 entrance. This alternative, however, also pr ovides enhanced access to employment centers along Chase Parkway and Sunnyside Avenue in the vicinity of Exits 18 and 19. Conceptual Alternative 8 This alternative would have impacts similar to those described for Conceptual Alternative 7 except that the major retail empl oyers in the vicinity of Bank Street would not be dislocated. There also may be a relocation of two add itional major employers, one along Chase Parkway south of I-84 in the vicinity of Exit 18, and one near the new intersection of West Main and South Main Streets where the magne t school property may be acquired. 4.3 Visual/Aesthetic Resources 4.3.1 Existing Conditions Visual and aesthetic resources in the study area include ridgelines, parks, historic sites and/or neighborhoods, and streetscapes. Notable resources include th e historic Union Station, a landmark tower visible from I-84, Route 8, and much of Waterbury. The Waterbury Green on West Main Street, inclusive of its monuments and sculptures, is also a visual and aesthetic resource, as is Saint Anne’s Church on East Clay Street. Anothe r feature unique to Waterbury is the “Holy Land,” characterized by a large cros s positioned on a ridgeline, visible over several miles. The Naugatuck River, winding its way fr om north to south through Waterbury, bisecting the city, is also an aesthetic natural resour ce in the region, though it disappears from view somewhat as it rests at lower elevations throu gh the heart of the city. Nonetheless, the I- 84/Route 8 Interchange with its el evated and stacked roadway structures creates a visual barrier that is prominent in views of th e area from varied vantage points. Additional information regarding visualization is provided in Chapter 7 of this report. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 46 4.3.2 Visual/Aesthetic Impacts Conceptual Alternative 6 In general, under Conceptu al Alternative 6 there are expected to be minor impacts to the visual setting of the study area . Since Conceptual Alternative 6 is limited primarily to modifications and additions to the local road network, the visu al effect will also be localized, meaning only those living and working nearby will have their view shed affected or altered. Conceptual Alternative 7 I-84 and Route 8 already comprise a substantive component of the study area visual backdrop. Conceptual Alternative 7 will in clude some additional new local roads (as with Conceptual Alternative 6) as well as substantial reconfiguration of the mainline highways and associated ingress and egress ramps (up to eight new bridge structures are estimated). Those new highway elements can be expected to intensify their predominance in the visual setting of the area; however the overall heights of the I-84 mainline bri dge spans will be lower in elevation than the existing stacked viaduct structure. Conceptual Alternative 8 Conceptual Alternative 8 is expected to have imp acts similar to those of Conceptual Alternative 7 with some additional effects. This alternativ e would include a number of new bridge and/or ramp structures associated with the relocation of Route 8 to the east of the Naugatuck River. In addition, the potential acquisition of the South End nei ghborhood school property under Conceptual Alternative 8 could ha ve an adverse impact on the visual setting of that specific neighborhood. A positive visual benefit resulting from this alternative is the reclaiming of riverfront property on the west si de of the Naugatuck River. The relocation of Route 8 will open up some prime land and may allow for so me attractive waterfront development. 4.4 Historic Resources 4.4.1 Existing Conditions Historic Resources For this screening study, an Area of Potential Effect (APE) of 500 feet was defined. The State Historic Preservation Office (SHPO) has not yet reviewed this proposed APE. It will be formally considered by SHPO during future design studies that will include formal documentation required to satisfy NEPA. Potentia l historic and archaeological resources within the 500-foot APE were identified as follows: through consultation with the SHPO; review of available maps provided by local planning depart ments and historical societies; and through searches of the State Register of Historic Pla ces, the Historic American Engineering Record, and of the National Register Information System Data base. In addition to this research, portions of the study area were field checked in November, 2004. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 47 There are numerous resources that may be eligible for listing on the National Register of Historic Places (NRHP) in the study area. They include several two-to-four-story brick industrial buildings (such as the Waterbury Rolling Mills) that date from around 1900, which are located on East Aurora and Freight Streets. Two potentially historic railroad crossings are located at Bank Street and at Freight Street. Throughout the Bunker Hill, Brooklyn, and Downtown neighborhoods of Waterbury, the study corridor closely parallels densely settled residential areas, many of which contain homes and churches that are well over 50 years of age and may also be eligible for inclusion on the (NRHP). This includes the Saint Anne’s church noted earlier. The three NRHP listed resources that fall within the APE are shown in Table 4-2. Table 4-2 National Register of Historic Places within Area of Potential Effect Propert y Location Description Protection Downtown W aterbury Historic District Bounded by Main, Meadow, and Elm Streets 106 buildings of various styles dating from 1850–1950 Listed on the National Register of Historic Places Hamilton Par k Bounded by Silver and East Main Streets, Idylwood Ave., Plank Rd., the Mad River and I-84 Historic Park designed by George Dunkelburger in 1903 Listed on the National Register of Historic Places Riverside Cemetery 496 Riverside Street Cemetery with Gothic- style, stone gatehouse and iron fence surrounding the grounds Listed on the National Register and as a National Historic Site Archeological Resources Due to the history of the area, locations of arch eological sensitivity can be expected to be found all along the Naugatuck River an d throughout the study area. Specific locales of potential archeological resources have not yet been determined for this project. As the project progresses to the preliminary design phase these areas will be identified and consultation will be sought with the State Archaeologist to determine significance. Section 4(f) Properties Section 4(f) of the Department of Transportation Act of 1966 protects historic resources eligible for listing or listed on the NR HP, public parks and recreation areas, and wildlife/waterfowl preserves from adverse impacts. Historic 4(f) resources were listed in the foregoing section. Information on public parklands and wildlife and waterfowl refuges was obtained from consultation with the Connecticut Department of Environmental Protection (DEP) and review of maps and local documentation. Section 4(f) resources in the study area include: Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 48 • Hayden Park; • The Waterbury Green; • Library Park; • Edmund Rowland Park; • Chase Park; • West Dover Street Playground; • Rolling Mill Playground; • Hamilton Park; and • Washington Hill Park. 4.4.2 Historic, Archeological, and Section 4(f) Resource Impacts Conceptual Alternative 6 Some of the local roads to be improved under Con ceptual Alternative 6 appear to abut the edges of the Downtown Waterbury National Register Historic District. These improvements will primarily be enhancements to existing streets at the district’s edge and consequently the impact to this historic district is expected to be minor . No other impacts to historic or Section 4(f) resources are anticipated under Conceptual Alternative 6. Conceptual Alternatives 7 and 8 Historic and Section 4(f) resource impacts associat ed with Conceptual Alternatives 7 and 8 are expected to be similar to those described for Conceptual Alternative 6. In addition, these alternatives will be located near Riverside Cemete ry, a historic and Section 4(f) resource due to its listing on the NRHP. 4.5 Community and Institutional Resources 4.5.1 Existing Conditions There are a wide variety of community and institutional faci lities within the project study area including public schools, churches , fire stations, police stations, hospitals, post offices, libraries and museums. There are approximately five places of worship in the study area. Other community facilities and resource s within the study area include: • Barnard School; • City of Waterbury Public Library; • Central Naugatuck Valley Community College; • Kennedy High School; • Kingsbury School; • Maloney School; • Mattatuck Museum; Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 49 • Saint Mary’s Hospital; • State Street School; • Teikyo Post University; • University of Connecticut, Waterbury Branch; • Washington School; • Waterbury Hospital; and • West Side School and West End Middle School Complex. 4.5.2 Community Facilities and Resources Impacts Conceptual Alternative 6 Conceptual Alternative 6 may require acquisition of a portion of the Maloney Inter-district Magnet School parking lot at the proposed new T-intersection at South Main and South Elm Streets. Access to some other community facil ities may be indirectly benefited by improved access on local roads in the northeast quadrant of the study area. No other direct impacts to community facilities and resources are anticipated with th is alternative. Conceptual Alternative 7 This alternative, similar to Conceptual Alte rnative 6, will have no impacts on community facilities and resources. In addition, no impact to the magnet school is anticipated. This alternative is also expected to result in enhanced access to the Central Naugatuck Valley Community College off of Chase Parkway on the north side of I-84 near Interchange 19. No other direct impacts to community facilities and re sources are anticipated with this alternative. Conceptual Alternative 8 This alternative may have the same impacts as Conceptual Alternative 7 on community facilities and resources. However, this alternative ma y require full acquisition of the magnet school located at the reconfigured intersection of South Main and South Elm Streets. 4.6 Environmental Justice 4.6.1 Existing Conditions Title VI of the Civil Rights Act of 1964 requires th at “no person in the United States shall, on the ground of race, color, or national or igin be excluded from participation in, be denied the benefits of, or be subjected to discri mination under any program or activity receiving Federal financial assistance.” In 1994, President C linton issued Executive Order 12898, Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations. The Executive Order further amplifies Title VI by providing that “each Federal agency shall make achieving environmental justice pa rt of its mission by identifying and addressing, as appropriate, disproportionately high and adve rse human health or environmental effects of its programs, policies, and activities on minority populations and low-income populations”. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 50 This section of the screening report responds to this mandate by identifying the presence of low income and minority (environmental justice or EJ) populations within the study area using 2000 U.S. Census data. An environmental justice population is considered to occur where the concentration of the target populations is substantially higher th an surrounding geographic areas. In addition, environmental justice populations as defined by the COGCNV were considered. With that approach, environmental justice populations are considered to exist where the percentage of the popul ation that is minority or low in come is 25% or more than the concentration of such populations in a relevant geographic comparison area. Data on EJ populations in the study area is shown in Table 4-3. The study area as a whole can be considered an EJ population with approximate ly 67 percent minority as compared with 33 percent in the City of Waterbur y and just 16 percent in the COGCNV region. Eight percent of the study area population is below th e poverty level, which is less than that in the City of Waterbury overall and comparable to the pe rcentage in the COGCNV region. The highest percentage EJ population in the st udy area resides north of I-84, north of Silver Street and across Route 8 to Route 73 (Watertown Avenue). Ther e are also concentrated EJ populations on the south side of I-84, west of Route 8 in the Brookl yn section of Waterbury and on the south side of I-84, east of Route 8, largely on the eas t side of South Main Street. Table 4-3 EJ Populations Study Area City of Waterbury COGCNV Region %Minority 66.7% 33% 16.2% low Poverty 8% 16% 8.6% 4.6.2 Impacts to Environmental Justice Populations Conceptual Alternative 6 Conceptual Alternative 6 may be expected to have an overall beneficial effect on access to community resources and employment opportunities for EJ populations as the entire study area constitutes an EJ region within the City of Waterbury. Conceptual Alternatives 7 and 8 Conceptual Alternatives 7 and 8 may have the same beneficial effects as Conceptual Alternative 6. However, a closer look at the Census Bl ock groups within the study area relative to percentage of minority populations indicates that there may also be some adverse impacts to the most highly concentrated EJ popul ations within the study area itself with these alternatives. Potential residential property acquisitions under both alternatives and impacts to the magnet school property under Conceptual Alternative 8 may create a direct negative impact to EJ Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 51 neighborhood cohesion more so than would be experienced by the general population of the study area as a whole or the City of Waterbury. 4.7 Surface Water and Groundwater 4.7.1 Existing Conditions Surface Water There are several watercourses wi thin the study area. These watercourses are listed below and are briefly described as they relate to the existing I-84 and Route 8 Interchange. Watercourses that are not classified by the DEP for water qual ity are presumed Class A, which is the default classification assigned where wate r quality data is unavailable. • Naugatuck River : The Naugatuck River runs north-south through the study area, generally paralleling Route 8, wh ich is located west of the river. Within the study area there are several crossings of the Naugatuck Ri ver; West Main Street and Freight Street (north of the I-84/Route 8 Interchange), and Bank Street and Washington Avenue (south of the interchange). The freight and commuter rail tracks cross the Naugatuck River three times within the study area, all south of the interchange near the Naugatuck River’s confluence with the Mad River. The surface wa ter quality classification of the Naugatuck River is C/B, indicating an existing classifi cation of C, with the goal of attaining a classification of B. • Mad River: The Mad River flows into the study area from the east and essentially parallels I-84 on the north. From Hamilton Park, located southwest of the Route 69 (Silver Street) and East Main Street inte rsection, the Mad River crosses Route 69 and then flows behind the Brass Mill Center and Commons. The river then submerges, passing under I-84, and then re-emerges north of Liberty Street. From here the river flows to the south of I-84, between Mill Street and River Street, crossing South Main Street and Washington Avenue (northeast of this intersection). South of Washington Avenue, the Mad River discharges into the Naugatuck Rive r. The surface water quality classification of the Mad River is B. • Steele Brook : Only a small portion of Steele Brook lies within the study area. Steele Brook flows in a southerly direction, along th e eastern side of Route 73 (Watertown Avenue). The brook crosses East Aurora Street before crossing Route 8, just northeast of Route 8 Interchange 35 (Route 73 ). Steele Brook empties into the Naugatuck River just east of Route 8 at this location. The surface water quality classification of the Steele Brook is B. • Hop Brook : West of the I-84/Route 8 Interchange, there are two smaller unnamed streams located partia lly within the study ar ea that are associated with the Hop Brook watershed. One of these streams flows north to south along the western edge of the Naugatuck Valley Community College campus and crosses Chase Parkway, I-84, and Country Club Road, before exiting the st udy area. The second unnamed stream flows north to south from the vicinity of Chas e Parkway through the Teikyo Post campus and Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 52 then exits the study area. The surface water quality classification of both of these watercourses is A. Groundwater and Public Water Supplies According to DEP GIS data, there are no potentia l well fields, sole source aquifers, aquifer protection zones, well-head zones, or stratified drift aquifers in the immediate vicinity of the proposed project. Groundwater is classified as GB throughout most of the study area. However, there are a few locations where the groundwater is classified as GA. These locations include the western portion of the study area in the vicin ity of West Main Street and Chase Parkway, an area to the southwest of the I-84/Route 8 Interchange near Porter Street and the Metro-North Waterbury Branch, and an area northwest of the I-84/Route 8 Interchange between Aurora Street and Route 73. The City of Waterbury, Bureau of Water, provides drinking water to residents in the study area. The water is supplied primarily from surface rese rvoirs located in Litchfield County. The water is piped from the reservoir to the Harry P. Danaher Water Treatment Plant located in Thomaston prior to being distributed to City of Waterbury customers. A few sma ll areas in the western portion of the study area are not se rved by the City of Waterbury, Bureau of Water. There are no public water supply reservoirs or stratified drift aquifers in the immediate vicinity of the proposed project. 4.7.2 Impacts to Surface and Groundwater Conceptual Alternative 6 No adverse impacts to any groundwater resources are expected with Conceptual Alternative 6. This alternative is also e xpected to have no adverse impact on any surface waters. Conceptual Alternatives 7 and 8 Conceptual Alternatives 7 and 8 may have some im pact to rivers and streams at locations where new support structures are cons tructed adjacent to or across these water bodies. Both alternatives include a modified river crossing on Sunnyside Avenue and new support structure for the interchange itself over the Naugatuck Rive r. They each also include potential impacts to an unnamed stream in the vicinity of Intercha nge 19. Additionally, while the Mad River flows underground through the core of the study area, the widening and reconstr uction of Interchanges 30 and 33 on Route 8 as well as Interchange 23 on I-84 may have an impact on this resource, especially if substantial excavat ion is required. Finally, Conceptu al Alternative 8 also includes modified crossings of the Naugatuck River on Freight and West Main St reet which may impact the Naugatuck River in those locales. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 53 4.8 Floodplains 4.8.1 Existing Conditions Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps and GIS data were reviewed to identify 100-ye ar floodplains within the project study area. Those adjacent to, or in close proximity to the existing I-84/Rout e 8 Interchange right-of-way are described below . • Naugatuck River : The 100-year floodplain associated with the Naugatuck River parallels Route 8 and tends to be wider (approximate ly 300 feet wide) along the western side of the river, north of the I-84/ Route 8 interchange. The wi dth of the 100-year floodplain gradually narrows as it follows the rivers edged passing under the interchange southward to the crossing with the freight rail line. The 500-year floodplain associated with the river is primarily located east of the river a nd is most expansive north of the interchange where it extends eastward approximately 2,000 feet. • Mad River : The 100-year floodplain associated with the Mad River is continuous through the study area. The 100-year fl oodplain ranges from approxima tely 200-feet wide, at its narrowest point, south of I-84, to its widest point of approximately 1,100-feet wide north and east of Silver Street. • Hop Brook : At the extreme western edge of the study area, the 100-year floodplain associated with the Hop Brook watershed’s Welton Brook lies north of I-84 on either side of Chase Parkway in the vicinity of the Naugatuck Valley Community College campus. At its widest point in the study area, the floodplain is approximately 500 feet. • Steele Brook : The 100-year floodplain associated with Steele Brook at the northern edge of the study area lies between Route 8 a nd Route 73 (Watertown Avenue). This floodplain, at its widest point in the study area is 850 feet. 4.8.2 Impacts to Floodplains Conceptual Alternative 6 The new or improved local roads, including the new roundabout, propos ed as part of Conceptual Alternative 6 all occur with in the Naugatuck River 500-year floodplain. The proposed new connector road from Riverside to Union Ave nue may be partially located in a 100-year floodplain. Consequently, there may be some adve rse effects to floodplain resources with this alternative. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 54 Conceptual Alternative 7 Conceptual Alternative 7 would have the same floodplain impacts as Conceptual Alternative 6. In addition, the Naugatuck River 100-year flood plain may be further impacted by new support structures for the new intercha nge configuration and by the ne w crossing extending Sunnyside Avenue to Meadow Street. Conceptual Alternative 8 Conceptual Alternative 8 would have the same floodplain impacts as Conceptual Alternative 7. Additionally, the proposed We st Main Street and Freight Street crossings of the Naugatuck River may further impact 100-year floodplain resources. 4.9 Wetlands 4.9.1 Existing Conditions Wetlands in the study area were id entified using DEP GIS Data. Ther e are several wetlands in the Hop Brook watershed, west of th e I-84 and Route 8 Interchange. A large wetland is located south of I-84, southeast of the Chase Parkway and Country Club Road in tersection, and is characterized by Carlisle muck soils. Another wetland area, also characterized by Carlisle muck, is located between I-84 and the Chase Parkway and West Main Street intersection. 4.9.2 Impacts to Wetlands Conceptual Alternative 6 No impacts to wetlands are anticipated under Conceptual Alternative 6. Conceptual Alternative 7 and 8 Conceptual Alternatives 7 and 8 may have an impact on wetlands in the vicinity of the Interchange 19 westbound off ramp and associated modified local roads. Wetlands may also be potentially impacted where reconfiguration of Interchange 18 is proposed and where Chase Parkway would be widened south of I-84. 4.10 Endangered Species According to the DEP Natural Diversity Database there are no records of any threatened or endangered species or species of special concern w ithin the project study area. The U.S. Fish and Wildlife Service, in correspondence dated Novemb er 8, 2004, noted that there are no federally- listed or proposed, threatened, or endangered species or critical ha bitat known to occur within the study area. Therefore, no impacts to this resource are anticipated. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 55 4.11 Hazardous Materials Risk Sites 4.11.1 Existing Conditions Due to the prevalence of industrial land use within the proposed project area, there is a high risk for encountering contamination during project c onstruction. Information from the Environmental Protection Agency (EPA) Toxics Release Inve ntory (TRI) was used to identify potential hazardous sites. There are 18 TRI hazardous waste sites identified in the study area where toxic releases have been reported. Of these 18 sites, two are active or archived superfund sites. Thes e two sites are located southeast of the I-84 and Route 8 Interchange, with in a cluster of hazardous materials risk sites bounded by South Leonard Street, South Main St reet, and Washington Avenue. Generally, the hazardous materials risk sites are located along the CONRAIL freight rail line, which runs north- south and parallel to Route 8. 4.11.2 Impacts to Hazardous Materials Risk Sites Conceptual Alternative 6 Conceptual Alternative 6 has potential to encounter hazardous materials during project construction of local roads in the vicinity of the Freight Street industrial area and in any location where the project may interface w ith the rail line. This would include the new connector roads proposed between West Main Street and Bank Street. Conceptual Alternative 7 and 8 Conceptual Alternatives 7 and 8 would have the sa me potential to encounter hazardous risk sites as Conceptual Alternative 6. In addition, these alternatives have the potential to disturb hazardous risk sites in the vicinity of the pr oposed reconfiguration and/or reconstruction of several exits including Interchanges 22 and 23 on I-84 and Interchange 30 on Route 8. 4.12 Farmlands 4.12.1 Existing Conditions The U.S. Department of Agriculture (USDA) Natural Resource Conservation Service (NRCS) soils information was used to identify prime and statewide important farmland soils within the study area. These soils have not be en field checked to determine if they have been developed and/or otherwise altered sinc e the mapping, which would disqua lify them as farmland, or to determine if they are actively farmed. The data indicates that there is prime farmland to the immediate northwest of the I-84 and Route 8 interchange in the vicinity of Chase Park, as well as to the southwest of the interchange, in close proximity to Riverside Cemetery and Barnard School. There are additional farmland soils of statewide importance shown along th e western edge of Route 8, both north and south of the I-84 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 56 and Route 8 Interchange. The prime farmland soils are described as Agawam Fine Sandy Loam with 8 to 15 percent slopes and Woodbridge Fine Sandy Loam with 3 to 8 percent slopes, and the farmland soils of statewide importance are Paxt on and Montauk with 8 to 15 percent slopes. Farther from the I-84 and Route 8 Interchange, at the western edge of the study area, there are large patches of prime farmland soils, as well as farmland soils of statewide importance, south of Interstate 84 in the vicinity of Country Club Road There are also prime farmland soils and statewide important farmland soils north of I-84 in the vicinity of Park Road, West Main Street, and Rowland Park, as well as Gr andview Avenue. East of the I-84 and Route 8 Interchange, there are small and scattered prime farmland soils and additional soils of statewide importance at the eastern edge of the study area in the vicinity of Route 69 (Silver Street) and East Main Street. There is also a small area of prime farmland soils and additional soils of statewide importance south of Interstate 84 at the corner of Washington Avenue and Sylvan Avenue. 4.12.2 Impacts to Prime Farmlands Due to the developed nature of the study area, no significant impacts to prime farmland soils are anticipated from the proposed alte rnatives. Areas where these soils occur and may be affected by the project alternatives are in use for purposes other than farmi ng and the potential for future agricultural use is negligible. 4.13 Air Quality 4.13.1 Air Quality Attainment Status The Clean Air Act of 1970 and subsequent am endments established National Ambient Air Quality Standards (NAAQS) for six criteria pollutants including carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), lead (Pb), ozone, and particulate matter (PM). The Clean Air Act required states to monitor regiona l air quality to determine if regions meet the NAAQS. If a region exceeds any of the NAAQS, that part of the state is classified as a non- attainment area for that pollutant, and the state must develop an air quality plan, called a State Implementation Plan (SIP), that will bring that region into compliance. Motor vehicles are sources of CO, ozone precursors, and PM em issions. Other sources include stationary sources such as power plants and boilers, area sources such as bakeries painting activities, and non-road vehicle sources su ch as construction and farm equipment. The current (CT DEP, December 2006) air qualit y attainment designations for the Central Naugatuck Valley Region, which is included with in the Greater New York City Air Quality Region, are presented below for the six criteria pollutants. • Carbon Monoxide: The entire state of Conn ecticut is now designated as being in attainment for CO. • Ozone: The entire state of Conn ecticut is designated as non-attainment for the one-hour ozone standard. The Central Naugatuck Valley region is classified as a “serious non- Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 57 attainment area” for the one-hour standard. Th e region must meet the ozone standard by 2007. In April of 2004, the EPA determined the entire state of Connecticut to be in moderate non-attainment for the eight- hour ozone NAAQS. The maximum attainment date is projected to be June 2010. • PM: EPA has established NAAQS for two size ranges of PM. The entire state of Connecticut is currently in attainment of PM 10 (particulate matter with a diameter of 10 microns or less). In January of 2005, the EPA classified the Greater New York City Air Quality Region, which includes the project study area, as non-attainment for PM2.5 (particulate matter with a diam eter of 2.5 microns or less). • NO2, Pb, and SO2: The entire state of Connectic ut is in attainment for these pollutants. 4.13.2 Impacts to Air Quality The primary source of potential air quality impact s with this project would be motor vehicles. The project alternatives are intended to enhance the existing roadway infrastructure to improve safety and reduce congestion. They will not increas e traffic volumes on the highway mainlines in and of themselves, but will be c onfigured to respond to growth in travel demand that will occur in the area over time. Nonetheless, there may be some localized change to air quality as new ramps and intersections alter tra ffic flows and potentially add tra ffic to some new spot locations in the study area. In summary, no significant adve rse impacts to air quality are anticipated and some beneficial effect may occur if congesti on and related idling of vehicles is reduced. 4.14 Noise 4.14.1 Existing Conditions The Federal Highway Administration’s Noise Ab atement Criteria (NAC) documented in 23 CFR 772, Procedures for Abatement of Highway Traffic Noise and Construction Noise is based on Land Use Activity Categories. La nd uses considered most sensitive to highway noise are designated as either Land Use Activity Category A or B. Land Use Activity Category A includes lands on which serenity and quiet are of extrao rdinary significance and serve an important public need and where the preservation of th ose qualities is essential if the area is to continue to serve its intended purpose. Such uses include outdoor amphitheatres, outdoor concert pavilions, and National Historic Landmarks with significant outdoor use. Land Use Activity Category B includes picnic areas, recreation areas, pl aygrounds, active sports areas, park s, residences, motels, hotels, schools, churches, libraries, and hospitals. Category A and B land uses in the study area were identified using existing land use maps and GIS data. There are no Category A land uses within the study area. Category B land uses include: • All residences; • The schools as identified in Sect ion 6 on community resources; • The parks as identified in S ection 4 on historic resources; • Saint Mary’s Hospital; and Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 58 • Waterbury Hospital. 4.14.2 Impacts to Noise Sensitive Receptors The noise sensitive receptors in the project st udy area occur in an urban environment where a heightened level of backgr ound noise is common. I-84 and R oute 8 are existing highway structures that contribute to that background noise under existing conditions. The project alternatives will move these highway elements as well as local roads closer to some noise sensitive resources, particularly residences. Conse quently, all of the alternatives may have some limited adverse noise impacts but are not expected to elevate area noise levels significantly. Areas of particular concern in clude Waterbury Hospital and the residential neighborhoods close to Interchanges 18 on I-84 and 30 on Route 8. Ther e may be some particular yet minor adverse noise effects under Conceptual Alternatives 7 and 8 in these locations. 4.15 Summary Matrix Table 4-4 summarizes the results of the screening level environmental analysis. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 59 Table 4-4 Potential Adverse Impact Summary Matrix Resource Conceptual Alternative 6 Adverse Impacts Conceptual Alternative 7 Adverse Impacts Conceptual Alternative 8 Adverse Impacts Land use & Neighborhoods Up to 22 partial or full acquisitions Up to 90 partial or full acquisitions Minor neighborhood impacts Up to 108 partial or full acquisitions including school. Major Employers None At least 5 major employers dislocated At least 5 major employers dislocated Visual None Minor adverse – intensifies highway elements of visual setting Intensifies highway elements of visual setting Historic and 4(f) Minor adverse if roads abutting downtown historic district are widened Located adjacent to historic cemetery Located adjacent to historic cemetery Community Facilities Minor impact to magnet school None Adverse effect if magnet school is acquired Environmental Justice None Minor impact to EJ neighborhoods Adverse effect if magnet school is acquired Surface and Groundwater None New highway support structures and reconfigured bridges may have some adverse effect on rivers and streams New highway support structures and reconfigured bridges may have some adverse effect on rivers and streams Floodplains Proposed roundabout in 500-year floodplain New connector road in 100 year floodplain Same as Conceptual Alternative 6 New highway infrastructure may impact 100 year floodplain Same as Conceptual Alternative 6 New highway infrastructure may impact 100 year floodplain Reconstructed local road bridges may impact 100 year floodplain Wetlands None Some potential impacts at new/reconfigured egress ramps, Interchanges 18 and 19 Some potential impacts at new/reconfigured egress ramps, Interchanges 18 and 19 Hazardous Materials Potential to disturb risk sites associated with industrial land use Potential to disturb risk sites associated with industrial land use Potential to disturb risk sites associated with industrial land use Farmlands None None None Air Quality None None None Noise Minor adverse effects Minor ad verse effects Minor adverse effects Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 60 5 Cost and Constructability 5.1 Discussion of Conceptual Alternatives and Cost Estimates 5.1.1 Conceptual Alternative 6 This alternative involve s only minor structural improvements. Four new bridges and ten new retaining walls are proposed, w ith no requirements for miscellaneous & temporary structures anticipated. Three bridges would be demolished unde r this alternative. Repairs would be made to all existing structures within the project lim its, except for the three bridges being demolished. While this is the least costly alternative in terms of initial capital cost, it is likely to be at least as expensive as the Full-Build alternatives in te rms of life cycle cost, due to the tendency for construction costs outpacing inflation over time. 5.1.2 Conceptual Alternative 7 This alternative is one of tw o Full-Build structure alternat ives, and involves shifting the alignment of I-84 over the Nauga tuck River to the south, and reconstruc ting the I-84/Route 8 Interchange in approximately the same footprin t as the existing interchange. In addition, a portion of Route 8 northbound would be shifted to the east side of the river, and several bridges along the I-84 and Route 8 corridors in the vicinity of the interchange would be constructed or replaced. A total of 46 new bridges and 29 new retaining walls are proposed for this alternative. For several of the bridges within the interchange itsel f, pier placement will be very limited and will depend on the maintenance and protection of tra ffic and construction staging sequencing. In addition, crane access to the proposed bridges within the interchange is expected to be limited. Launching trusses or other means is expected to be necessary to be able to construct this alternative. For these reasons, we have used slightly higher uni t costs for the proposed bridges for this alternative than for Con ceptual Alternative 8. Also, it is expected that this alternative will require a number of temporary structures and other works in order to be able to maintain traffic during construction. A total of 30 existing structures would be demolished and a total of 13 existing structures would be retained and repaired for this alternative. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 61 5.1.3 Conceptual Alternative 8 This alternative is the second of two full-build a lternatives, and involves shifting the alignment of I-84 over the Naugatuck River to the sout h, shifting a portion of Route 8 northbound and southbound to the east of the river, and reconstructi ng the I-84/Route 8 Interchange to the east of the river. In addition, several bridges along the I-84 and Route 8 corridors in the vicinity of the interchange would be c onstructed or replaced. A total of 52 new bridges and 34 new retaining walls are proposed for this alternative. For a few of the bridges within the interchange itself, pi er placement will be very limited and will depend on the maintenance and protection of traffic and construction staging sequencing. However, we would expect that cranes would generally be able to access the site, resu lting in conventional construction for all of the proposed bridges. It is expected that this alternative will require some temporary structures and other works in order to be able to maintain traffic during construction; however, the number and complexity of such struct ures is expected to be significantly fewer than that required for Conceptual Alternative 7. A total of 40 existing structures would be demolis hed and a total of two existing structures would be retained and repaired for this alternative. 5.1.4 Summary of Costs Conceptual capital cost estimates including all structural and civil items have been developed for each Conceptual Alternative. These costs are in 2006 dollars given the conceptual stage at which alternative development and phasing schedules are. As the Conceptual Alternatives continue to be refined throughout this study, future year cost s will be developed and reported in a financial plan for the project. The cost estimates include the taking of property that might be necessary to construct these alternatives. A simple formula was used that multiplied the number of estimated property takes by an assumed average cost of $ 1,000,000. As alternatives are refined, such costs will be refined as appropriate. Refer to Table 5-1 for tabulation of all costs a ttributed to each Conceptual Alternative. More details on costs are provided on the appe ndix CD at the back of the report. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 62 Table 5-1 Summary of Conceptual Alternative Costs by Major Cost Items Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Civil Highway Costs $72,356,575 $224,702,833 $245,560,209 Structural Bridge Costs $154,068,190 $636,864,853 $572,962,498 Subtotal A $226,424,765 $861,567,686 $818,522,707 Lump Sum Items $66,795,306 $254,162,468 $241,464,199 Subtotal B $293,220,070 $1,115,730,154 $1,059,986,906 Additional Items $67,660,616 $256,617,935 $243,796,988 Total Cost $360,880,686 $1,372,348,089 $1,303,783,894 Total Cost (Rounded) 1 $360,900,000 $1,372,300,000 $1,303,800,000 Total Cost based on an assumed 2025 year of construction 2 $588,112,000 $2,236,259,000 $2,124,633,000 1 Year 2006 dollars 2 Year 2025 dollars based on a 2.75% inflation rate provided by ConnDOT 5.2 Constructability Constructability refers to the relative ease with which an alternative can be constructed. Given modern construction techniques and unlimited funding, virtually anything can be built; however, it is the responsibility of ConnDOT to justify the expenditure of public funds, assure that work zones are safe, and minimize inconvenience on users of the transportation system. Constructability can also substa ntially affect the total cost for project construction. Constructability is inclusive of stage construction, maintenance of traffic and work zone safety. Construction staging includes the planned transiti on of construction from the existing facility to the newly completed facility. Transitional traffic cross-overs, temporary paved embankments, and interim lane configurations are included under this item. Pr oper barricades, physical barriers and warning devices provide work zone safety to the contractors’ manpower and equipment. Also, special construction techniques and methods may need to be used to construct the project in such a restrictive environment. Since the level of conceptual planning detail and scope of this study does not allow for evaluating the maintenance and protection of traffic, construction access and staging, and construction methods in detail, a lump sum co st for each alternative was assumed based on Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 63 professional judgment and past experience. Th e lump sum cost assumed for each alternative takes into account several consid erations. Primarily, these were: • Cost of temporary bridges required to ma intain traffic during construction staging. • Cost of the relatively large amount of tem porary and/or permanent sheet piling compared to similar structures. This is due to larg e grade separations in a congested area and substructure construction immediately adjacent to live traffic. • Cost of temporary access roads and temporar y structures on access roads, taking into account the congested site. • General cost of working in a confined area. • Cost of temporary work trestle s which are anticipated to be required in order to construct piers in the river. In addition, impact to work zones must be c onsidered when planning a new highway project. Work zone impacts assessment is the proces s of understanding and managing the safety and mobility impacts of a road construction, maintenan ce, or rehabilitation project. Assessing work zone impacts is important for developing eff ective Transportation Management Plans (TMPs) that provide for safety, mobility, and quality while maintaining, rehabilitating, and rebuilding highways. Work zone impacts will be assessed more completely in the final phase of this study and it is expected that strategies to mitigate impacts will include: • Alternate network options; • New and temporary roadway connections; • Frontage road development; • Protection of traffic; • Development of Intelligent Transportation Systems (ITS); • Others. For each of the three Conceptual Alternatives, a preliminary review has been made to identify the potential issues that could arise during co nstruction. The information presented in the following paragraphs is not meant to reflect a detailed evaluation of all constructability issues, but to provide general guidance on selecting a Preferred Alternative. A more comprehensive list of issues will be developed for the Preferred Alternative. 5.2.1 Conceptual Alternative 6 Conceptual Alternative 6 has the fe west issues with regard to constructability. The structural components of the interchange that are going to be modified are limited to the consolidation of the Interchange 21 and 22 exit ra mps in the eastbound direction. This will require diverting traffic to other ramps on a temporary basi s until the new exit ramp is completed. Another structural element that is not related to the interchange but is part of the local street network is the extension of Sunnyside Avenue over the Naugatuck River. It is anticipated that the structure and approaching roadways can be bui lt without any disruption to traffic. It is unclear at this stage of the study whether this new connection will result in constructability issues if a new interchange is subsequently cons tructed. Once a Preferred Alterna tive is defined, Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 64 the staging of this connection will have to be closely coordinated with the development of the new interchange structures. The remaining components of this alternative relate to intersection improvements, local road improvements, transit route enhancements and bi cycle and pedestrian amenities. Each of the improvements is relatively short-te rm and will impose little inconvenience to users of the system. It should be noted that the tr ansit and pedestrian improvements included in this alternative are not likely to make a significant impact in terms of reducing vehicle trips on the highways. They would, however, provide travel options for shorter-d istance trips. During the construction of a new interchange, the early provision of more lo cal connector roads, pedestrian and bicycle routes, and transit can assist in maintainin g mobility through and within the project area, particularly within the city. 5.2.2 Conceptual Alternative 7 Conceptual Alternative 7 would be the most difficult to construct. The primary reason is that Route 8 would have to be reconstructed over its existing footprint. To accomplish this, temporary roadways would have to be construc ted to carry traffic while Route 8 is being demolished and new structures erected. The new temporary roadways would have to be built on the east side of the Naugatuck Ri ver, requiring new bridges. Once the permanent structures are complete, the temporary roadways would be demolished and removed. For several of the bridges within the interchange itself, pier placement will be very limited and will depend on the maintenance and protection of tr affic and construction staging sequencing. In addition, crane access to the proposed bridges within the interchange is expected to be limited. Launching trusses or other means are expected to be necessary to be able to construct this alternative. This alternative would have to be analyzed in great depth to fully understand and plan how the construction would be phased and traffic maintain ed over the construction period. It appears that the construction of this alternat ive is feasible, although difficult. By removing the Route 8 ramps to and from the south, space can be provided for the relocation of Route 8 to the east side of the river. From that point the I-84 spans can be c onstructed. It may be necessary to remove the upper deck (I-84 eastbound) without disrupting the fl ow of traffic to and from Route 8 to the north. The constructability of this alternative is indeed complex and would likely require special construction methods and equipment, increasi ng the overall cost and timeframe for project completion. 5.2.3 Conceptual Alternative 8 Conceptual Alternative 8 would be the less difficult of the two Full Build alternatives to construct. While still incredibly complex and costly, Conceptual Alternative 8 differs in that it can be constructed almost entirely offline. That is, the new mainline segments of I-84 and Route 8 would be on parallel alignments, which would not necessitate diverting traffic from the existing highway during constructi on. Of course, once the new segments of highway are ready Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 65 to tie into the existing alignment, temporary roadways would have to be built to maintain the flow of traffic; however, the extent of temporary construction and the duration over which motorist would be inconvenienced would be minimized. For a few of the bridges within the interchange itself, pier placement will be very limited and will depend on the maintenance and protection of traffic and construction staging sequencing; however, it is expected that cranes would genera lly be able to access the site, resulting in conventional construction fo r all of the proposed bridges. Again, the key to this alternative is the removal of the Route 8 ramps and the relocation of the Route 8 mainline to the east side of the river. The I-84 spans can, for the most part, be constructed offline and the staging of the project should occur from west to east, in general. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 66 6 Financial Analysis 1 6.1 Benefit-Cost Analysis A benefit-cost analysis is a systematic eval uation of the economic advantages (benefits) and disadvantages (costs) of a set of investment alternatives. Typically, a “Base Case” is compared to one or more Conceptual Alterna tives which have some significant improvement compared to the Base Case. The analysis evaluates incrementa l differences between the Base Case and the Conceptual Alternative(s). In othe r words, a benefit-cost analysis tries to answer the question: What additional benefits will result if this alternative is undertaken, and what additional costs are needed to bring it about? The objective of a benefit-cost analysis is to tran slate the effects of an investment into monetary terms and to account for the fact that benefits generally accrue over a long period of time while capital costs are incurred primar ily in the initial years. The primary transportation-related elements that can be monetized are travel time costs, vehicle operating costs, safety costs, ongoing maintenance costs, and remaining capital value (a combination of capital expenditure and salvage value). 6.1.1 Benefits The benefits of a transportation investment ar e typically estimated by comparing the amount of travel time, vehicle miles traveled and expected nu mber of crashes for the alternative to the Base Case. The physical projection of the change brought about by each alternative is usually accomplished by engineering analysis. The second step is translating these physical benefits into monetary values. Typically, the following benefits are included in the analysis: • Travel-Time Savings • Vehicle Operating Cost Savings • Safety Benefits • Air Quality Benefits 2 6.1.2 Costs In economic terms, the cost of a transportation investment is the value of the resources that must be consumed to bring the project about. The total value of construction and any additional maintenance costs must be estimated. It is impor tant to note that the analysis does not emphasize who incurs the cost but rather aims to include any and all costs that are involved in bringing about the project. Typical costs include: 1 Financial Analysis chapter is taken from Mn/DOT Office of Investment Management Website http://www.oim.dot.state.mn.us/EASS/ 2 Litman, Todd – Transportation Cost and Benefit Analysis – Air Pollution Costs Victoria Transport Policy Institute (www.vtpi.org) Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 67 • Capital Costs • Major Rehabilitation Costs • Routine Annual Maintenance Costs • Remaining Capital Value (RCV) 6.2 Benefit Cost Ratio By converting user benefits to monetary values , benefit-cost ratios were calculated for each of the three Alternatives. The calculation for B/C is simply the total discounted benefits divided by the total discounted costs. Conc eptual Alternative 8 had the highe st B/C ratio with a value of 1.03. Conceptual Alternative 7 had a B/C value of 0.95 and Conceptual Alternative 6 came in at 0.29. According to this analysis, Conceptual Altern ative 8 is the most cost effective project of the three Alternatives. Given that the B/C ratio is over a value of 1.0, the ratio also indicates that the long-term benefits outweigh the costs and the project is economically justifiable. It should be noted that although the Full Build alternatives yield relatively high B/C ratios and indicate strong economic justifica tion for a new interchange, the tota l cost of such a project is considerable. The main reason th at the benefits outweigh the costs for Conceptual Alternative 8 is the substantial time savings that would be real ized by the millions of vehicles that use the interchange per year as a result of additional ca pacity and improved safety. It should also be noted; however, that the existing st ructure cannot be maintained forever. There will be a point in time in which a major rehabilitation, or comple te replacement, would be necessary. Such a situation could indefinitely take the structure of f-line, resulting in major disruption to mobility, quality of life, the environment, and economic gr owth – not to mention a significant financial investment. Table 6-1 lists the results of the analyses. A more detaile d methodology on the benefit-cost analysis can be found on the appendix CD at the back of this report. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study _____________________________________________________________________________________________ Wilbur Smith Associates June 2007 68 Table 6-1 Benefits and Costs Travel Time Safety Operating Emission Total Benefits Conceptual Alternative 6 $17,391,000 $2,035,000 $172,822,000 $420,000 $192,668,000 Conceptual Alternative 7 $1,183,434,000 $91,840,000 $615,216,000 $13,926,000 $1,904,415,000 Conceptual Alternative 8 $1,152,944,000 $91,840,000 $600,335,000 $13,180,000 $1,858,298,000 Capital Maintenance Total Costs Conceptual Alternative 6 $328,843,000 $751,000 $329,594,000 $29,816,000 $104,560,000 Conceptual Alternative 7 $907,930,000 -$114,946,000 $792,984,000 $294,719,000 $309,023,000 Conceptual Alternative 8 $732,216,000 -$122,675,000 $609,541,000 $287,582,000 $279,093,000 B/C Conceptual Alternative 6 0.29 Conceptual Alternative 7 0.95 Concep tua l Alternative 8 1.03 Discounted Total Costs Benefits Costs Discounted Total Benefits Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 69 7 Visualization To help understand the visual impact of the new interchange alternatives, photosimulations were developed on an aerial photograph of the I-84/ Route 8 Interchange looking north. Figure 7-1 shows the existing configuration of the interchange, which would look very similar under Conceptual Alternative 6. Figure 7-1: Existing Interchange Figure 7-2 illustrates the Conceptual Alternative 7 alignment which would reconstruct I-84 to the south of the existing structure, while maintain ing the new Route 8 structure on its existing footprint. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 70 Figure 7-2: Conceptual Alternative 7 Figure 7-3 illustrates Conceptual Alternative 8’s alignment, which would bisect the industrial properties on the east side of the Naugatuck River and reclaim the land currently occupied by the existing Route 8 ramps. This C onceptual Alternative would have a greater visual impact because it is considerably different from the current interchange layout. Numer ous opportunities exist to redevelop adjacent industrial land, as well as accommodate new waterfront uses, with this alternative. Overall, it is an ticipated that this Conceptual Alternative will result in more developable land than the other alternatives and will open up more riverfront property for new uses. The vertical profile will be significantly lo wer than the existing structure and the intent is to construct visually appealing and safe pedestrian access to the west side of the structure. Every attempt will be made to minimize the physic al barrier created by the realignment. The example land uses depicted in this photos imulation are not intended to be viewed as recommendations for future development and have not yet been reviewed by the City. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 71 Figure 7-3: Conceptual Alternative 8 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 72 8 Summary This Chapter serves as a summary of the major findings reported in this report. 8.1 Capacity Analysis of Interchange System The analysis of system capacity based on projected Year 2030 traffic demand resulted in a drastic improvement in Level of Service on the highway and asso ciated ramps for both Conceptual Alternatives 7 and 8. Conceptual Alternative 6 would be a modest modification from the No Build scenario. Both Conceptual Alternatives 7 and 8 operate at LOS D or better conditions, with Conceptual Alternative 7 perfor ming slightly better. Table 8-1 summarizes the number of ramps and segments according to LOS. Table 8-1 Future (2030) Level of Service Summary Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Freeway Analysis – I-84 LOS A-C 0 13 7 LOS D-E 15 15 21 LOS F 13 0 0 Freeway Analysis – Route 8 LOS A-C 12 18 15 LOS D-E 10 6 7 LOS F 2 0 0 Ramp Analysis – I-84 LOS A-C 1 34 34 LOS D-E 4 6 6 LOS F 39 0 0 Ramp Analysis – Route 8 LOS A-C 16 22 15 LOS D-E 12 8 11 LOS F 6 0 0 TOTALS LOS A-C 29 87 71 LOS D-E 41 35 45 LOS F 60 0 0 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 73 8.2 Routing Analysis A vehicle routing analysis was performed to ensure that the Conceptual Alternatives were not negatively impacting access to local destinations within the City of Waterbury. All three Conceptual Alternatives maintain adequate conn ectivity to local destination, with Conceptual Alternative 8 being superior in enhancing access to locations north of the interchange. Table 8-2 lists the improvements to downtown locations. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 74 Table 8-2 Summary of Routing Analysis Origin Destination Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 I-84 EB Waterbury Hospital    St Mary’s Hospital    Government Center    Proposed Transportation Center    Parking Garages    I-84 WB Waterbury Hospital   5 St Mary’s Hospital    Government Center    Proposed Transportation Center    Parking Garages    Route 8 NB Waterbury Hospital    St Mary’s Hospital    Government Center    Proposed Transportation Center    Parking Garages    Route 8 SB Waterbury Hospital    St Mary’s Hospital   5 Government Center   5 Proposed Transportation Center   5 Parking Garages   5 Legend 5 Improved Routing  No Routing Improvements 8.3 Geometric Improvements Each Conceptual Alternative was evaluated with respect to the number of substandard geometric deficiencies improved over the No Build scenari o. Both Conceptual Alternative 7 and 8 improve a majority of substandard conditions with Concep tual Alternative 7 performing slightly better. Table 8-3 lists the total number of remaining geometric deficiencies. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 75 Table 8-3 Summary of Geometric Deficiencies Geometric Deficiency Number of Deficiencies Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Left-hand Ramps 8 1 1 Substandard Grade 3 0 0 Substandard Acceleration Length 6 0 0 Substandard Deceleration Length 3 0 0 Substandard Ramp Spacing 21 5 6 Substandard Curve Radius 1 2 2 Substandard Superelevation 2 0 0 Total 44 8 9 8.4 Local Road Impacts A qualitative assessment of local road impacts wa s performed to determine the local City roads that are likely to experience a net increase or d ecrease in traffic volume due to the Conceptual Alternatives. Conceptual Alternative 8 has the greatest number of new intersections so it is expected that local traffic c onditions will be optimal under this alternative. Conceptual Alternative 7 does the best job of decreasing volume at existing inte rsections. Table 8-4 lists the number of intersections expected to witness a ne t increase or decrease in traffic volume in future Year 2030. Table 8-4 Impact of New Local Connections on Downtown Intersections Number of Intersections antic ipated to Existing Intersections Increase in Volume Decrease in Volume to be Improved Conceptual Alternative 6 4 9 7 Conceptual Alternative 7 2 15 5 Conceptual Alternative 8 5 7 14 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 76 8.5 Environmental Impacts Based on an analysis of secondary source environmental data, it was determined that there are no fatal flaws to developing each of the alternatives . Conceptual Alternative 8 potentially has the greatest impact upon the environm ent including property acquisitions. Table 8-5 summarizes the results of the environm ental impact analysis. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 77 Table 8-5 Potential Adverse Impact Summary Matrix Resource Conceptual Alternative 6 Adverse Impacts Conceptual Alternative 7 Adverse Impacts Conceptual Alternative 8 Adverse Impacts Land use & Neighborhoods Up to 22 partial or full acquisitions Up to 90 partial or full acquisitions Minor neighborhood impacts Up to 108 partial or full acquisitions including school. Major Employers None At least 5 major employers dislocated At least 5 major employers dislocated Visual None Minor adverse – intensifies highway elements of visual setting Intensifies highway elements of visual setting Historic and 4(f) Minor adverse if roads abutting downtown historic district are widened Located adjacent to historic cemetery Located adjacent to historic cemetery Community Facilities Minor impact to magnet school None Adverse effect if magnet school is acquired Environmental Justice None Minor impact to EJ neighborhoods Adverse effect if magnet school is acquired Surface and Groundwater None New highway support structures and reconfigured bridges may have some adverse effect on rivers and streams New highway support structures and reconfigured bridges may have some adverse effect on rivers and streams Floodplains Proposed roundabout in 500-year floodplain New connector road in 100 year floodplain Same as Conceptual Alternative 6 New highway infrastructure may impact 100 year floodplain Same as Conceptual Alternative 6 New highway infrastructure may impact 100 year floodplain Reconstructed local road bridges may impact 100 year floodplain Wetlands None Some potential impacts at new/reconfigured egress ramps, Interchanges 18 and 19 Some potential impacts at new/reconfigured egress ramps, Interchanges 18 and 19 Hazardous Materials Po tential to disturb risk sites associated with industrial land use Potential to disturb risk sites associated with industrial land use Potential to disturb risk sites associated with industrial land use Farmlands None None None Air Quality None None None Noise Minor adverse effects Minor ad verse effects Minor adverse effects Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 78 8.6 Capital Cost Estimates Cost estimates were developed for each Conceptu al Alternative and are listed in Table 8-6. Conceptual Alternative 7 was the most expensive. This is largely due to the amount of temporary structures required to maintain traffic operations during construction. Conceptual Alternative 8 is the least expensive Full Build alternative. C onceptual Alternative 6 is the least expensive of the alternatives but maintains virtually all of the existing structure so a high repair cost has been included in the estimate. In addition, Conceptu al Alternative 6 would be the most costly to maintain over time since the useful life of repair s is much lower than the useful life of new construction. Table 8-6 Summary of Conceptual Alternative Costs by Major Cost Items. Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Civil Highway Costs $72,356,575 $224,702,833 $245,560,209 Structural Bridge Costs $154,068,190 $636,864,853 $572,962,498 Subtotal A $226,424,765 $861,567,686 $818,522,707 Lump Sum Items $66,795,306 $254,162,468 $241,464,199 Subtotal B $293,220,070 $1,115,730,154 $1,059,986,906 Additional Items $67,660,616 $256,617,935 $243,796,988 Total Cost $360,880,686 $1,372,348,089 $1,303,783,894 Total Cost (Rounded) 1 $360,900,000 $1,372,300,000 $1,303,800,000 Total Cost based on an assumed 2025 year of construction 2 $588,112,000 $2,236,259,000 $2,124,633,000 1 Year 2005 dollars 2 Year 2025 dollars based on a 2.75% inflation rate provided by ConnDOT 8.7 Benefit Cost Analysis Based on the assumptions listed above and the performance measures reported by the VISSIM model, benefit-cost ratios were calculated for eac h of the three Alternatives. The calculation for B/C is simply the total discounted benefits divided by the total discounted costs. Conceptual Alternative 8 had the highest B/C ratio with a value of 1.03. Conceptual Alte rnative 7 had a B/C value of 0.95 and Conceptual Alternative 6 cam e in at 0.29. According to this analysis, Conceptual Alternative 8 is the mo st cost effective project of the three Alternatives. Table 8-7 Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 79 lists the results of the analysis . Given that the B/C ratio is over a value of 1.0, the ratio also indicates that the benefits outweigh the costs and the project is economically justifiable. It should be noted that although the Full Build alternatives yield relatively high B/C ratios and indicate strong economic justifica tion for a new interchange, the tota l cost of such a project is enormous. The main reason that the benefits outweigh the costs for Conceptual Alternative 8 is the substantial time savings that would be realized by the millions of vehicles that use the interchange per year as a result of additional ca pacity and improved safety. It should also be noted; however, that the existing st ructure cannot be maintained forever. There will be a point in time in which a major rehabilitation, or comple te replacement, would be necessary. Such a situation could indefinitely take the structure o ff-line, resulting in major disruption to traffic, quality of life, the environment, and economic gr owth – not to mention a significant financial investment. . Table 8-7 Summary of Benefit-Cost Analysis Conceptual Alternative 6 Conceptual Alternative 7 Conceptual Alternative 8 Total Discounted Benefits $29,816,000 $294,719,000 $287,582,000 Total Discounted Costs $104,560,000 $309,023,000 $279,093,000 B/C Ratio 0.29 0.95 1.03 8.8 Ranking of Conceptual Alternatives Early in the study process, decisions were made regarding the weighting factors to be used for each study goal; since some issues were determined to be more important than others. Weights for each goal were defined on a scale from 1 to 5. The highest weighting score of 5 was assigned to Safety/Meets Design Standards, whereas the lowest weighting of 3 was assigned to Construction Cost and Intermodal Connections. Table 8-8 shows the relative weights for each criterion. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 80 Table 8-8 Criteria Weight Factors Criteria Weight Construction Cost 3 Life Cycle Cost 4 Constructability 4 Environmental Impact 3.5 Safety/Meets Design Standards 5 Connectivity 4 Economic Development 3.5 Intermodal Connections 3 Traffic Operations/Capacity Accommodation 4.5 Source: Wilbur Smith Associates Based on the analyses completed coupled with professional judgment, each Conceptual Alternative was given a 1 to 5 score (1 being the lowest and 5 being the highest) based on its ability to satisfy each goal. To come up with a total score for ranking, each score was multiplied by the goal’s weighting factor and all weighted sc ores summed for each Conceptual Alternative. The scores were determined as follows: Table 8-9 is based on the weighted decision matrix used earlier in the study to evaluate the five Preliminary Alternatives. While this is a somewhat subjective rating system, it is based on the quantitative analyses presented in this report, an d is a good tool to assist in making an informed decision regarding selection of a Conceptual A lternative for the purpose of developing a final Preferred Alternative. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 81 Table 8-9 Ranking of Conceptual Alternatives 3 515391313 4 1414520520 4 5 20 5 20 1 4 4 16 3.5 5 17.5 4 14 2 7 13.5 5 1 5 2 10 5 25 4 20 4 1 4 4 16 4 16 5 20 3.5 1 3.5 2 7 4 14 5 17.5 3135153939 4.5 1 4.5 2 9 5 22.5 4 18 Decision Matrix for I-84/Rout e 8 Interchange Alternatives Rating (1 – 10) Weighted Rating Rating (1 – 10) Weighted Rating 76.5 Weighted Rating 4321 Rating (1 – 10) 104 120.5 Ranking of Alternatives No Build Alternative 7 Economic Development Environmental Impact Rating (1 – 10) Alternative 6 Criteria Relative Weighting (1 – 5) Weighted Rating Safety/Meets Design Standards Connectivity Total Scores Intermodal Connections Traffic Operations/Capacity Accommodation 127 Alternative 8 Construction Cost Constructibility Life Cycle Cost Grading Criteria 8.8.1 Construction Cost For the construction cost goal, the higher the scor e given translates to a lower construction cost. The No-Build – or do nothing – scenario does have the lowest overall construction cost, but the repair of the existing stru ctures over time will be significant. Based on construction cost alone, the No Build scenario was given a score of 5. Costs for the various Conceptual Alternatives are most affected by the significant structural costs associated with each alternative. For Conceptual Alternative 6, the structural costs are attributed primarily to maintaining the aging bridges that exist today and would remain in the future. The cost of maintaining the structures is significant and Conceptual Alternative 6 was therefore given a score of 3. Conceptual Alternative 7 is the most expensive alternative and this fact can be attributed to the complete reconstruction of th e I-84/Rte 8 interchange and the extensive number of temporary structures that would be required to maintain traffic during construction. Conceptual Alternative 7 was given a score of 1. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 82 Conceptual Alternative 8 would be slightly less expensive than C onceptual Alternative 7, and the cost is also attributed to the complete recons truction of the I-84/Rte 8 interchange. Conceptual Alternative 8 would still require temporary struct ures to maintain traffic during construction, but would have far fewer since most of the new alig nment will be constructed off-line. Conceptual Alternative 8 was also given a score of 1. 8.8.2 Life Cycle Cost For the life cycle cost goal, the higher the score given translates to a lower life cycle cost. It is estimated that the life cycle score for the No Build scenario is a 1. This is primarily based on the fact that the existing stacked viaducts, which are non-redundant structures, would need to be continuously repaired to preven t a major failure or collapse of the structure. In addition, these particular structures are difficult and expensive to repair, maintain, and improve, because of the difficulty involved in orde r to stage the work. This score al so takes into account the fact that multiple cycles of repair are anticipated on all structures during the lifetime of potential replacement structures. Conceptual Alternative 6 include s transit improvements, modifying signal timing, and improving signage and minor structural impr ovements. It is estimated that the life cycle score for this alternative is a 1. This score is based on the sa me reasoning given for the No Build. Conceptual Alternatives 7 and 8 are both full-build alternatives, which involve demolishing all existing viaducts and constructing new I-84 and Route 8 viaducts, new collector-distributor (C/D) viaducts, and new ramp structures. Due to the fact that the new structures constructed in each of these alternatives will have ve ry long life spans and will not require frequent repair and maintenance, the life cycle ranking for both was estimated to be a 5. 8.8.3 Constructability For the construction cost goal, the higher the sc ore given translates to the less expensive the alternative. The No Build scenario does not require any new structural modifications to the highway and local roadway network and is therefore given the highest ranking of 5. It should be noted that repair of existing structure is often difficult due to the existing configuration of the structure. Conceptual Alternative 6 maximizes the operation of the existing transportation system with minimal structural modifications to the highway and local roadway network. This alternative involves transit, signal timing, signage improveme nts, new local roads, and a couple of new bridges. Since Conceptual Alternative 6 does not require any structural modifications to I-84 and Route 8 mainline viaducts, this alternative is given a ranking of 5. Conceptual Alternative 7 represents a Full Build alternative which involves the replacement of both I-84 and Route 8 mainlines. Conceptual Alternative 7 poses the greatest construction challenge, since this alternative involves rebuilding the new Route 8 structures within the existing structural footprint. Special construction techniques would be needed for cranes and other machinery to operate in such a constricted work environmen t. In addition, this alternative would require the highest level Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 83 of effort in managing traffic operations while construction is ongoing. This alternative is therefore given the lowest ranking of 1. Conceptual Alternative 8, while still challenging in terms of constructability, is significantly simplifie d due to the fact that much of Route 8 will be constructed on new alignment away from the existi ng bridge footprint. The construction of this alternative lends itself to more traditional cons truction techniques and is therefore given a rating of 4. 8.8.4 Environmental Impact For the environmental impact goal, the higher the score given translates to a lower the environmental impact. The No Build will have little or no effect (score of 5) on just about all socioeconomic and environmental resources; however, under the No Build condition the existing traffic congestion and circulation problems that currently plag ue Waterbury and the surrounding transportation system will continue to exist and will only b ecome exacerbated over time, thereby further clogging infrastructure and adding to increased safety problems and delays. Since virtually the entire study area is comprised of an environmental justice (EJ) popul ation, it is very likely that this EJ population would be increasingly affected in an adverse manner by the increased traffic and circulation problems if no improvements are made. Additionally, increased traffic congestion over time will only exa cerbate air quality issues due to increased vehicle residence time in the study. Conceptual Alternative 6 will be similar to the No Build scenario, but will include some new local roads and a multi-use trail. Impacts are expected to be minima l so it was given a ranking of 4. Conceptual Alternatives 7 and 8 both have significant impacts on existing property and the Naugatuck River, although both attempt to mini mize these impacts to the extent possible. Conceptual Alternative 8 includes greater impact to existing properties, primarily because Route 8 is on a new alignment, but it can also be argued that these properties (many of them contaminated by hazardous materials) would be cleaned up to support new development. Conceptual Alternatives 7 and 8 were give scores of 2 and 1 respectively. 8.8.5 Safety/Meets Design Standards. For the safety/meets design standards goal, the hi gher the score given translates to a lower the negative impact. The safety of a roadway has much to do with the standards by which it has been designed. When I-84 was designed almost 50 years a go, design standards were different than they are today. The volume of traffic that the highway was expected to carry was far less than is realized today. In addition, the standards for ramp spacing and other geometric conditions were less stringent. The No Build scenario makes no geometric improvement s to the interchange and therefore, does not directly address deficiencies on the inters tate itself. A score of 1 is given. Conceptual Alternative 6 consolidates the closely spaced exit ramps of Interchanges 21 and 22 on I-84 eastbound, thereby making a minimal improvement to the overall safety of the system. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 84 A score of 2 is given. Concep tual Alternative 7 addresses the greatest number of geometric deficiencies within the study area .and is given a score of 5. Conceptual Alternative 8 has one more ramp spacing deficiency that Conceptual A lternative 7 and as such is given a slightly reduced score of 4. Both Full Build alternatives dramatically reduce the number of substandard conditions that exist in the No Build scenario. 8.8.6 Connectivity For the connectivity goal, the higher the score given translates to better connectivity to destination within Waterbury. The No Build scenario does not improve local road circulation nor does it provide improved connectivity to emerging development areas downto wn. For this reason it is given the lowest score of 1. Conceptual Alternative 6 improve s local connections within Waterbury and consists of new roadways and intersections in the downtown al ong with two new connector roads. Conceptual Alternative 6 improves transit c onnectivity and signal timing in the downtown area and provides new local road connections to facilitate cars, trucks, buses and pedestrian movement. For this reason Alterative 6 is given a score of 4. Concep tual Alternative 7 also provides a high level of connectivity through the use of collector-distributor (C/D) roads along I-84 and new local roads to improve circulation. Conceptual Alternativ e 7 is also given a score of 4. Conceptual Alternative 8 is given a score of 5 because it improves access to portions of the town that are poorly served today, such as the industrial land surrounding Freight Street. Conceptual Alternative 8 also provides more direct connectivity to Waterbur y Hospital and downtown destinations. 8.8.7 Economic Development For the economic development goal, the higher the score given translates to the better the alternative’s ability to accommodate and stimulate economic growth. The No Build scenario is given a score of 1 b ecause the existing transportation system is an impediment to economic growth. The traffic congestion projected to occur in 2030 will limit development opportunities. The Naugatuck Valley Development Corporation has economic development initiatives near the Jackson Street and Freight Street corridors. While all three Conceptual Alternatives accommodate access to this area, Conceptual Altern ative 8 would provide the most direct access from Route 8 and I-84. Also, recl aiming the land on the west side of the Naugatuck River where the existing interchange ramps to and from Ro ute 8 reside would make available prime river front land for new development. Conceptual Alte rnatives 6 and 7 would provide enhanced local road connectivity to downtown Waterbury and emerging development parcels, but Conceptual Alternative 6 would do li ttle to improve the conges tion that is projected to occur in 25 years. Therefore, Conceptual Alternatives 6 and 7 are given scores of 2 and 4 respectively. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 85 8.8.8 Intermodal Connections For the connectivity goal, the higher the score gi ven translates to the better the alternative’s interconnection with multiple tran sportation modes (i.e. bike, pedestrian, auto, truck, transit, freight, etc.). The No Build scenario would not improve or f acilitate the efficient interconnection between transportation modes. For this reason it is given the lowest score of 1. This goal is addressed most thor oughly by Conceptual Alternative 6, mainly due to the improved bicycle, pedestrian, local road, and transit connections, and is gi ven a score of 5. Conceptual Alternatives 7 and 8 both consist of improved lo cal road connections which improve access to the rail station. Also, both alternatives improve substandard ramp conditions that are currently challenging to trucks. For these reasons Conceptu al Alternatives 7 and 8 were both given a score of 3. 8.8.9 Traffic Operations/Capacity Accommodation For the traffic operations/capacity accommodation goa l, the higher the score given translates to the better the alternative’s abilit y to handle future travel demand. For each Conceptual Alternative, freeway segmen ts, weave areas and ramp junctions with LOS E and LOS F were identified as deficiencies. Th e number of operational/capacity deficiencies for each alternative was calculated and used as a basi s of ranking the alternatives. Since the No Build scenario does not improve any of the stat ed deficiencies it was given a score of 1. Conceptual Alternative 6 woul d improve one operational deficiency from the No Build condition. In all, there would be 44 operational deficiencies under this alternative. For this reason, Conceptual Alternative 6 is given a score of 2. Conceptual Alternative 7 would solve the greatest number of operation defici encies, with 8 remaining. Conceptual Alternative 8 leaves 9 deficiencies remaining. While it is possible that either of the Full Build alternatives can be further engineered to rectify some of these remaining deficiencies, the scores given to Conceptual Alternatives 7 and 8 at this point in the study process are 5 and 4 respectively. 8.9 Recommendation Comparing the results of the various analyses pres ented in this report for each of the Conceptual Alternatives, leads the Study Team to conclude th at Conceptual Alternative 8 would best satisfy the stated study goals. This alte rnative performs well with regard to improving traffic operations and reducing the number of substandard geometri c conditions currently present at the existing interchange. This alternative would provide the best connections with local Waterbury destinations and is expected to support local economic development efforts in the City. Finally, Conceptual Alternative 8 can be built with minimal disruption to traffic flow making it inherently easier to construct relative to the other alternatives. It also can be built using Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 86 conventional construction techniques because a majority of the structure would be built on new alignment. Throughout the study process, every considerat ion has been given to rehabilitating or constructing portions of the exis ting interchange to solve some of the many problems without the major expense of replacing the entire structure. It has become increasingly clear to the study team that the existing structure is fast approach ing the end of its useful life and does not lend itself to expansion in any way. The interchange is substandard with respect to the traffic demand that is currently placed upon it and should be repl aced with new structural components within the next 25 years. Finally, it is recommended that a Preferred Altern ative be selected for additional refinement and ultimately environmental review and design. As a preliminary recommendation, Conceptual Alternative 8 should be advanced as the long-term improvement alternative with elements of Conceptual Alternative 6 serving as near-term improvements. These two Conceptual Alternatives have complimentary features and w ould serve to improve the transportation system both prior to and during the construction of the interchange. This final alternative would be identified as Preferred Alternat ive 9 and, with the concurrence of study stak eholders, evaluated in greater depth and advanced as the fi nal recommendation of this feasibility study. Refinement of Alternatives I-84/Route 8 Waterbury Interchange Needs Study ___________________________________________________________________________________________ Wilbur Smith Associates June 2007 87 9 References Minnesota Department of Transportation. 2005. Benefit-Cost Analysis for Transportation Projects. Available: http://www.oim.dot.state.mn.us/EASS/ Litman, T. 2005. Transportation Cost and Bene fit Analysis: Techniques, Estimates and Implications, Victoria Transport Policy Institute. Available: www.vtpi.org Harwood, D.W. and Graham, J. L. 1983. Rehabilit ation of Existing Freeway-Arterial Highway Interchanges. Transportation Research Record 923, TRB, National Research Council, Washington, D.C., pp. 18-25.