3.0 Project Alternatives

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1 Whittier Bridge/I-95 Improvement Project EA/DEIR 3.0 Project Alternatives 3.1 INTRODUCTION This chapter provides a summary analysis of the potential project alternatives for the Whittier Bridge/I-95 Improvement Project and describes the methodology by which alternatives were comparatively evaluated. Reasons for eliminating project alternatives from further consideration are described. Alternative Merrimack River crossing and highway widening alignment alternatives are analyzed in detail. Summary analyses of alternative bridge types and shared-use path options are also included. 3.2 MERRIMACK RIVER CROSSING AND HIGHWAY WIDENING ALTERNATIVES The list of project alternatives includes the alternatives described in the Environmental Notification Form filed with the Massachusetts Executive Office of Energy and Environmental Affairs in June 2009 and as listed in the Certificate of the Secretary of Environmental Affairs on the Environmental Notification Form (EEA File # 14427, July 10, 2009). The alternatives include Merrimack River-crossing alternatives for the existing I-95 Whittier Bridge, and highway widening design alternatives for the I-95 corridor within the project limits from Newburyport through Amesbury and north into Salisbury. The following summarizes the No Build and Build Alternatives for the River Crossing Alternatives and Highway Widening Alternatives: No Build: The No Build Alternative will be analyzed in the EA/DEIR, in compliance with NEPA/MEPA requirements. This alternative would involve limited maintenance rather than replacing or rehabilitating the Whittier Bridge without additional travel lanes or breakdown shoulders. River Crossing Alternatives: - Progressive Alternative: The Progressive Alternative would replace the piers and superstructure in stages. In the first phase, a new southbound bridge would be constructed to carry southbound traffic. In subsequent phases, a new northbound bridge would be constructed to carry northbound traffic, the bridge would then be widened and traffic relocated. In the final phase, the existing bridge would be demolished Rehabilitation Alternative: This alternative would involve extensive rehabilitation of the existing structure to replace the deck, stringers, floor beams, most of the bracing, gusset plates, wire rope hangers and expansion joints. In addition, existing piers and footings that do not meet code would need to be replaced. No temporary bridge to carry traffic during construction would be constructed. Retrofit with Adjacent Structure Alternative: This alternative would be similar to the Rehabilitation Alternative with the addition of a temporary bridge to carry traffic during construction, maintaining three lanes of traffic in each direction on I-95. New 6-Lane Bridge Alternative: This alternative would provide two new bridges, carrying three lanes of traffic northbound and three lanes of traffic southbound. New 8-Lane East West Bridge Alternative: Under this alternative, two new 4-lane bridges would be constructed simultaneously to the east and west of the existing bridge. Traffic would then be transferred to the new bridges, and the existing bridge would be demolished. New 8-Lane East Bridge Alternative: This alternative would provide a new bridge to the east of the existing bridge, to which all traffic would be temporarily relocated. The existing bridge would then be demolished, and a second new bridge would be constructed in its place. When construction is completed, the two new bridges would be configured to carry four lanes of traffic northbound and four lanes of traffic southbound. New 8-Lane West Bridge Alternative: This alternative is similar to the previous alternative, except in this case a new bridge would be constructed to the west of the existing bridge, so that all six lanes of traffic could be relocated to the new bridge. The existing bridge would then be demolished and a new bridge would be constructed to carry northbound traffic. When completed, traffic would be reconfigured to four lanes northbound and four lanes southbound. Highway Widening Alternatives: - Inside Highway Widening Alternative (Northern Terminus to Route 286): The Inside Highway Widening Alternative would begin at the Route 110 interchange and end at the Route 286 interchange. The alternative would widen the northbound and southbound barrels within the existing median. - Outside Highway Widening Alternative (Northern Terminus to Route 286): The Outside Highway Widening Alternative would begin at the Route 110 interchange and end at the Route 286 interchange. This alternative would widen the northbound and southbound barrels to the outside of the existing highway Inside Northbound/Outside Southbound Highway Widening Alternative (Northern Terminus to Route 286): The Inside Northbound/Outside Southbound Highway Widening Alternative would begin at the Route 110 interchange and end at the Route 286 interchange. This alternative would widen the northbound barrel into the existing median and widen the southbound barrel to the outside of the existing highway. Outside Northbound/Inside Southbound Highway Widening Alternative (Northern Terminus to Route 286): The Outside Northbound/Inside Southbound Highway Widening Alternative would also begin at the Route 110 interchange and end at the Route 286 interchange. This alternative would widen the northbound barrel to the outside of the existing highway and widen the southbound barrel into the existing median. Northern Terminus to Route 110 Highway Widening Alternative: This alternative would involve widening both the northbound and southbound barrels with a fourth lane to the outside of the existing highway between Route 110 and I-95. The alternatives screening process described in this chapter is intended to identify feasible project alternatives for the project to carry forward in the detailed environmental impact assessment process, as detailed in Chapter Process A range of engineering, environmental, cost, and schedule screening criteria were developed with which the River Crossing and Highway Widening Alternatives were assessed. The screening criteria were developed based on the professional judgment of the senior professional staff of the project team and Massachusetts Department of Transportation Highway Division (MassDOT) and on previous experience of the senior professionals. The screening factors reflect the relevant factors affecting the feasibility of the alternatives. Once the screening criteria were finalized, project team members assessed each alternative for the criteria within their area of expertise and determined the rating for the particular alternative for those criteria. Alternatives were ranked on a three-point qualitative scale: Positive, Neutral, or Negative. Alternatives were ranked Negative if the alternative did not meet the criteria, Positive if the alternative met or exceeded the criteria, and Neutral if the alternative was not affected by the criteria. Numerous criteria were not employed in this screening process, as they were indistinguishable across alternatives (e.g., traffic noise exceeded Federal Highway Administration s Noise Abatement Criteria for existing conditions). Similarly, air quality did not vary between alternatives as the project would not include changes at interchange ramps/local streets and, 3-1

2 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Purpose and Need) therefore, would not result in a noticeable improvement in congestion at these locations. Likewise, the number of existing oil and hazardous materials and listed hazardous waste sites within the project corridor was not a distinguishing factor among the alternatives. It is important to note that, subsequent to the screening of alternatives described in this chapter, design development of the Preferred Alternative has resulted in a reduction in the amount of work required in order to construct the project. Specifically, the Pine Hill/Ferry Road Bridge will now be replaced in its entirety instead of being rehabilitated, as described in Section 3.5. This change is not reflected in the screening described in this chapter; however, it would not result in changes to the relative ranking of the alternatives as the change to the Pine Hill/Ferry Road Bridge is constant for all river crossing alternatives except for the Rehabilitation Alternative Screening Criteria Purpose and Need This criterion assesses the potential of each alternative to meet the Purpose and Need of the project. The Purpose and Need identifies the characteristics (geometry, safety, traffic, etc.) necessary to meet the basic requirements of the project purpose. For this project, these characteristics include meeting highway design standards and improving the cross section to provide for a safe project design (both highway and bridge crossing) while providing adequate capacity for projected future traffic volumes in the project corridor Highway Configuration The highway alignment alternatives corresponding to the selected bridge alternatives and the widening of the existing highway alternatives were qualitatively evaluated separately based on their ability to meet a proposed design speed of 70 mph. The proposed design speed established the range of design values for many of the geometric elements for the highway. The following categories were used for this evaluation: Horizontal Alignment: This factor evaluates the ability for a given alternative to meet the design requirements as set forth by the MassDOT and American Association of State Highway and Transportation Officials (AASHTO). This category also evaluates the ability of the alternative to provide the desired shoulder width of 10 feet. Vertical Alignment: This factor evaluates the ability for a given alternative to meet the design requirements as set forth by the MassDOT and AASHTO. The vertical alignment depends on the bridge type. All alternatives that involve constructing a new bridge can accommodate a profile change of up to an additional 6 feet, if necessary, for the type of bridge proposed. Impacts to Existing Infrastructure: This factor evaluates the impact to existing bridges and ramps along the project corridor Bridge Configuration The Bridge Configuration screening subcategories used to rate the proposed River Crossing Alternatives include the following: Design Standards/Complexities: This subcategory defines the relative difficulty in achieving compliance for each of the proposed alternatives with current AASHTO structural design standards. It also defines the level of design complexity associated with implementing such standards with the objective of providing bridge-service life of 75 years for each of the proposed alternatives. Structural Safety: This subcategory outlines whether any of the proposed alternatives may possibly present one or more structural safety concerns. Issues associated with structural safety may typically materialize either during construction and repair or throughout the service life of the structure. Constructability: This subcategory defines the level of construction complexity associated with each of the proposed alternatives. Constructability or construction complexity relates not only to constructing the new northbound and southbound bridges under either a progressive staging scheme or a staged-construction scheme, it also applies to retrofitting and rehabilitating the existing bridge as well as demolishing and removing the existing bridge. Context-Sensitive Structure: This subcategory defines how each of the proposed alternatives ranks from the standpoint of the context of the structure and its surrounding environment. Maintenance and Inspection: This subcategory defines how each of the proposed alternatives would rank from the standpoint of maintenance and inspection. The existing truss bridge comprises multiple non-redundant members, which are characterized by the fact that a failure of one main member, in either tension or compression, could cause the bridge to collapse. Accordingly, the frequency and depth of inspections and extent of maintenance associated with a truss-type structure would be far more extensive compared to the level of maintenance and inspection anticipated for a new girder type or signature (extradosed, tied arch, etc.) bridge structure. Life Cycle/Cost: This subcategory defines how each of the proposed alternatives rank from the standpoint of life cycle/cost, which seeks to define a threshold of benefits realized from the proposed structure over an extended period while minimizing financial cost. Financial cost includes not only the cost of building a new structure or rehabilitating an existing structure, but also includes the cost of maintenance and repair of that structure over time. Life cycle/cost is evaluated on an entire cycle over the long term Traffic To conduct the traffic analysis, the peak-hour conditions of summer Saturday AM northbound and Sunday PM southbound for future (2030) traffic were evaluated as the design scenario. For all measures, a base condition of good weather, good visibility, and no incidents or accidents was assumed. The traffic screening subcategories that were used to rate the proposed River Crossing and Highway Widening Alternatives included the following: Travel Time: The amount of time it takes a vehicle to traverse a given segment depends on the speed of vehicles and the number of lane changes that are occurring. To determine the average speeds for the different alternatives, a VISSIM model was calibrated for each of the conditions. Travel time will depend on the speed of vehicles and the number of lane changes that occur for merging, weaving, and diverging conditions. Level of Service (LOS): LOS is an indicator of operating conditions occurring on a given roadway. It is based on the freedom vehicles have to maneuver within the traffic stream and their proximity to other vehicles. As a result, it is measured by the density of the traffic stream in terms of passenger cars/mile/lane (pc/mi/ln). It is defined in the Highway Capacity Manual 2000 (HCM) by six levels A being the best and F is failure. Any given roadway can operate at a different LOS depending on the time of day, day of week, or period of year. For this analysis, the 2030 peak travel conditions (August Sunday PM Peak for southbound traffic and August Saturday AM Peak for northbound traffic) were analyzed to determine future operating conditions for a worst-case scenario. For a freeway segment, LOS C, a stable flow condition, is generally considered acceptable for peak flow. Base conditions for evaluating LOS for a freeway segment included the following: - Minimum lane width 12 feet; - Minimum right shoulder lateral clearance 6 feet between edge of travel lane and nearest obstacle/object that influences traffic behavior; - Minimum median lateral clearance 2 feet; - Traffic 100 percent passenger vehicles; 3-2

3 - Lanes of traffic More than five lanes in each direction; - Interchange spacing Five intersections per mile; and - Level terrain. If any of these conditions are not met, the LOS on the segment will deteriorate. Highway Capacity Software was used to evaluate each of the alternatives. Capacity: The HCM defines capacity as the maximum sustained 15-minute flow rate that can be accommodated by a uniform freeway segment. Capacity can be derived from the HCM speed-flow relationships; therefore, any impacts to the free-flow speed of the interstate will lower the capacity of the roadway. The conditions that affect free-flow speed include: - Lane width < 12 feet; - Right shoulder lateral clearance <6 feet; - Number of lanes (more lanes make it easier to avoid slower traffic); and - Interchange density (more interchanges result in more weaving to exit interstate). Based on these characteristics, free-flow speed (FFS) is derived as follows using the HCM. FFS = Base FFS f LW f LC f N f ID f LW = Adjustment for Lane Width f LC = Adjustment for Lateral Clearance f N = Adjustment for Number of Lanes f ID = Adjustment for Interchange Density Right-of-Way Conceptual designs of each proposed alignment were evaluated to determine the impacts outside of the existing right-of-way (ROW) for the following three categories: Fee Taking: These are strip takings from abutting properties that are necessary to keep the actual highway within the ROW. Permanent Easement: These are required in instances where a design element, such as a retaining wall, drainage feature or critical slope, is located near or outside the ROW line. The easement would allow for maintenance and/or access. Temporary/Construction Easement: These are required when constructing a design feature located near the ROW line requires temporary access and/or impacts on abutting properties Cost This criterion assesses the relative cost differences between the River Crossing and Highway Widening Alternatives. The cost differentiators include constructability, site access, construction staging ease/restraints, traffic management plans, ease of existing Whittier Bridge demolition and need to inspect and strengthen the structure, and schedule impact on extended contractor overhead costs of the specific alternative to meet the budget of the project. The resulting cost assessment is a qualitative indicator of the relative cost effectiveness of the project scope as implemented through the various alternatives. Due to the conceptual nature of the highway and river crossing alternatives at the time of the assessment and the difficulty inherent in determining costs at the conceptual level of design, the cost analysis was qualitative, not quantitative Construction Utility Relocation: This criterion assesses the relative difficulty or complexity required to relocate or reconstruct existing municipal or private aboveground (e.g., electric power lines) or underground (e.g., water, sewer) utilities adjacent to or crossing the I-95 project corridor. Constructability/Demolition of Existing Structure: This criterion assesses the relative constructability differences between the bridge and highway alternatives. The constructability differentiators include safety of operation, site access, construction staging ease/restraints, traffic management plans, ease of existing Whittier Bridge demolition, and need to inspect and strengthen the structure prior to demolition. The resulting constructability assessment is a qualitative indicator of the relative constructability for the project scope as implemented through the various alternatives. Maintenance of Traffic: This evaluates how a given alternative lends itself to traffic management, including the ability to meet vertical and horizontal design standards for the temporary alignments and the number of times traffic will be shifted to new alignments Schedule This criterion assesses the relative schedule differences between the bridge and highway alternatives. The schedule differentiators include constructability, site access, construction staging ease/restraints, traffic management plans, ease of existing Whittier Bridge demolition and need to inspect and strengthen the structure, and schedule of the specific Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Right-of-Way) alternative to meet the budget of the project. The resulting schedule assessment is a qualitative indicator of the relative schedule duration for the project scope as implemented through the various alternatives Environmental Stormwater The selected highway and bridge alternatives were qualitatively evaluated based on their potential for implementing stormwater management measures that meet the requirements of the 2008 Massachusetts Wetlands Protection Act regulations and the Massachusetts Department of Environmental Protection (MassDEP) Massachusetts Stormwater Handbook. Consistent with the regulations, the following criteria was chosen to evaluate each alternative: Potential to Provide Water Quality Treatment: This evaluates the likelihood that a given alternative can be designed to conform with MassDEP s Standard 4 of the Stormwater Management Standards to remove 80 percent of the average annual post-construction load of Total Suspended Solids (TSS). Also considered is whether the required water quality volume can be captured and treated and whether proper pre-treatment can be provided (especially prior to infiltration in a critical area). Potential to Provide Recharge Volume: This evaluates the likelihood that a given alternative can be designed to conform to MassDEP s Standard 3 of the Stormwater Management Standards to infiltrate the required recharge volume as determined in accordance with the Massachusetts Stormwater Handbook. This would require the annual recharge from the post development site to approximate the annual recharge from the pre-development conditions based on soil types. Potential to Provide Peak Flow Attenuation: This evaluates the likelihood that a given alternative can be designed to conform to MassDEP s Standard 2 of the Stormwater Management Standards so that post-development peak discharge rates do not exceed predevelopment peak discharge rates. This would require incorporating stormwater detention volume or other attenuation measures to control runoff rates from the new development. Potential for Staging of the Stormwater Management Measures during Construction: This evaluates the likelihood that a given alternative can be designed to conform to MassDEP s Standard 8 of the Stormwater Management Standards so that erosion, sedimentation and other pollutant sources during construction can be properly controlled by the maintenance of the existing drainage system, staging of the new drainage system improvements and implementing a compliant stormwater pollution prevention plan. 3-3

4 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Environmental) Potential to Manage Stormwater from The Redevelopment Portion of the Project: This evaluates the likelihood that the redevelopment portion of a given alternative can be designed to conform to MassDEP s Standard 7 of the Stormwater Management Standards so that Standard 2, Standard 3 and the pretreatment and structural stormwater Best Management Practices (BMP) requirements of Standards 4, 5 and 6 can be met to the maximum extent practicable. Potential to Treat Stormwater from the Bridge Structure: This evaluates the likelihood of providing water quality treatment of runoff from the bridge structure or a portion of the structure by piping runoff to BMPs located on the landside of the bridge. Each highway alternative was evaluated with regard to the criteria above for each of five major drainage zones (watersheds) that have been established for the corridor. The drainage zones were established based on generalized watershed areas, or highway segments with distinct drainage characteristics, as follows: Zone 1: Southern project terminus to the Merrimack River (approximately 2,700 linear feet); Zone 2: The Whittier Bridge structure and a portion of the I-95 approaches (approximately 1,200 linear feet); Zone 3: North of the Whittier Bridge to the Boston & Maine Railroad (approximately 4,600 linear feet); Zone 4: North of the Boston & Maine Railroad to the ridge line north of Route 286 (approximately 9,200 linear feet); and Zone 5: The ridge line north of Route 286 to northern project terminus (approximately 1,300 linear feet). Drinking Water Quality The I-95 corridor passes through water supply protection areas in Newburyport to the south of the Merrimack River and in Salisbury at the northern end of the project corridor. In Newburyport, the Zone II Wellhead Protection Areas for existing water supply wells located both west and east of I-95 intersect with the I-95 mainline. In Salisbury, I-95 passes through the Zone IIs associated with three existing water supply wells located to the east of the highway and north of the project limits, and through a Zone I for one water supply well. Bartlett Spring Pond in Newburyport is an active surface water supply and lies within 400 feet of the existing I-95 southbound roadway. Any widening of the I-95 southbound lanes to the west would result in alterations to the existing terrain and additional impervious surface within 400-feet of the pond. MassDOT has consulted with DEP on the status of the Zone A surface water supply protection zone for Bartlett Spring Pond. DEP, in an dated April 6, 2011, stated that there is currently no 400-foot Zone A associated with Bartlett Spring Pond since it is not so listed in 314 CMR 4.00, and it was not approved by DEP after December 29, 2006 in accordance with 314 CMR 4.06(3). DEP does note that the use of Bartlett Spring Pond as a public water supply must be protected and maintained and that conditions that are reasonable to protect the pond as a drinking water source may be included in any permit approvals (e.g., strict compliance with stormwater standards.) DEP also notes that the pond may be listed as a public water supply/outstanding Resource Water (ORW) in the next revisions to 314 CMR 4.00 and that the current status may change. If it does become listed as a Class A ORW, the provisions applicable to waters designated as public water supplies and ORWs in 314 CMR 4.00, such as no discharge of dredged or fill material into wetlands or waters within 400-feet of the high water mark of Bartlett Spring Pond per 314 CMR 4.06(1)(d)(1) without a variance under 314 CMR 9.00, would be applicable. Additionally, provisions in other regulations pertaining to ORWs and/or waters designated as public water supplies may also apply. Alternatives that would not result in additional impervious surface (and additional volume of stormwater to be treated) in the Zone IIs were judged to be Positive. Build Alternatives that would result in additional impervious area discharged in Zone IIs (with concomitant treated stormwater volumes) were judged to be Neutral (based on the assumption that all stormwater discharges would be treated in compliance with stormwater performance standards). Any alternative that would result in highway widening within 400-feet of Bartlett Spring Pond, given the potential for the creation of a future 400- foot Zone A water supply protection area around the pond, was judged to be a Negative ranking. Wetlands Wetland resources within the project corridor are generally limited to specific areas of the project. At the Merrimack River crossing, the wetlands are a mix of freshwater (e.g., Bordering Vegetated Wetlands) and coastal resources associated with the Merrimack River (e.g., Coastal Bank, Coastal Beach, Land Subject to Coastal Storm Flowage, Rocky Intertidal Shore, Salt Marsh). To the north of the river in Amesbury and Salisbury, the wetlands are generally inland resource areas which lie along outside edges of the I-95 corridor or within the infield of ramps at Exit 58 (Route 11) and Exit 59 (I-495). In general, any River Crossing and Highway Widening Alternatives that would result in no permanent direct impacts to wetland resources were judged to be Positive. River Crossing and Highway Widening Alternatives that would result in minimal permanent direct impacts to wetland resources (e.g., less than 5,000 square feet of vegetated wetlands or minor indirect impacts to wetland resource areas (e.g., salt marsh) on the banks of the Merrimack River) were judged to be Neutral. River Crossing and Highway Widening Alternatives that would result in greater permanent direct impacts to wetland resources (e.g., greater than 5,000 square feet of vegetated wetlands or destruction of salt marsh requiring a Variance) were judged to be Negative. Visual/View Points The Whittier Bridge is a prominent feature in the visual landscape for residents of the area, drivers passing over the bridge on I-95, and boaters on the Merrimack River, as well as pedestrians in parks and bicyclists on local trails with views of the river. Any alternative that alters the view to or the view from the Whittier Bridge by demolishing the bridge, modifying or replacing the bridge structure, would have an impact on these groups. Similarly, modifications to I-95 under each of the proposed alternatives would have an effect on both the view from the roadway for drivers and the view to the roadway from adjacent properties and roadways. This criterion will qualitatively evaluate the level of impact of each alternative. Photographs of existing conditions and renderings of views for each alternative and site visits will be used in this evaluation. A Positive rating was given for alternatives that would result in no change or improved views to and the views from the bridge and the roadway. An alternative that would result in minimal changes was considered Neutral. Alternatives that would impair or compromise views were considered Negative. Historic The Whittier Bridge is considered to be eligible for listing on the National Register of Historic Places as a historic structure and is known as a significant historic feature of the Massachusetts Interstate Highway network. Any alternative that would demolish or alter the existing bridge or construct an additional bridge structure adjacent to the existing bridge would likely result in a finding of Adverse Effect from the Massachusetts Historic Preservation Officer under the provisions of Section 106 of the National Historic Preservation Act. 3-4

5 For this criterion, any alternative that would not result in any changes to the historic character and elements of the existing Whittier Bridge was considered to be Positive. Build Alternatives that would result in minimal changes to the existing bridge, but not demolish the existing bridge, were determined to be Neutral. Build Alternatives that would result in the demolition and replacement of the existing bridge were considered to be Negative. Navigation The Whittier Bridge includes four piers within the waterway and five spans or openings beneath the bridge. There are two navigation channels under the bridge the north and south channels which maintain vertical clearances of 56 feet and 32 feet, respectively. The north channel (herein referred to as Federal Channel) is mapped and maintained by the U.S. Army Corps of Engineers (USACE) as a 150-foot-wide federal channel with a 7-foot channel depth. The south channel is referred to as Steamboat Channel according to the U.S. Coast Guard Light List, Volume 1, Atlantic Coast, dated The Federal Channel is between piers 3 and 4, and the Steamboat Channel is between piers 1 and 2. According to the hydrographic survey performed beneath the bridge, the span in the middle of the bridge between piers 2 and 3 is not used for navigation because of shallow depths. The remaining openings located between existing piers 1 and 4, adjacent to the north and south banks, respectively, also do not provide safe passage for navigation because of shallow depths. This criterion considers potential impacts during both the construction (temporary) and operational (permanent) phases of the new bridge project. The construction of either of the Build Alternatives includes both the construction of a new bridge crossing as well as the demolition of the existing Whittier Bridge. Operational impacts include the location and number of bridge piers within the Merrimack River and the potential impact to the existing navigation channels and existing river boat traffic. A Build Alternative potentially interfering with existing navigation caused by either a complicated or extensive construction/demolition period, or with the existing navigation channels after construction was considered Negative. Alternatives considered having less potential for construction/demolition impacts and no permanent impacts to navigation are Neutral. An alternative judged to pose the potential for improvements to navigation was considered Positive Screening Results No Build Alternative Purpose and Need The No Build Alternative would not result in any changes to the existing Whittier Bridge, nor would it result in improvements to the cross-section along I-95 in the project corridor; therefore, no safety improvements or highway capacity improvements would be constructed. For these reasons, this alternative was rated Negative. The pier locations of the existing bridge are shown in Figure 3-1; however, in accordance with NEPA and MEPA requirements, the No Build Alternative is carried forward as a point of comparison with the Build Alternative(s) that meet the project s Purpose and Need. Highway Configuration Horizontal Alignment: This alternative would maintain the existing horizontal alignment. This alternative would not provide for the desired shoulder widths, resulting in a Negative rating. Vertical Alignment: This alternative would maintain the existing vertical alignment. The rating for this category is Positive. Impacts to Existing Infrastructure: No impacts to existing infrastructure are expected. The rating for this category is Positive. Bridge Configuration Under this alternative, the existing bridge would remain in place in lieu of constructing a new structure using any of the River Crossing Alternatives; however, because of the indeterminate nature of much of the existing structure, together with the extensive state of deterioration as identified in MassDOT bridge inspection reports and other records, a major rehabilitation of the structure would be necessary. As discussed in detail under Section , conducting such major repair is not considered a prudent course of action. Accordingly, with the exception of Hydraulics and Context-Sensitive Structure, which have Neutral ratings, this alternative has Negative ratings for the remaining four Bridge Configuration subcategories: Design Standards/Complexities, Structural Safety, Maintenance and Inspection, and Life Cycle/Cost. Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( No Build Alternative) Traffic The No Build Alternative would maintain the bridge cross section of six lanes with no shoulders. The following criteria describe the impact the three-lane section in each direction with no shoulders would have on traffic conditions: Travel Time: Travel time depends on the speed of vehicles and the number of lane changes that occur for merging, weaving, and diverging conditions. Although the posted speed on I-95 is 65 mph, speeds across the bridge are slower because of the constraints of the roadway. In the northbound direction, the average peak-hour speed would be mph, taking 34.1 seconds to cross the bridge. For southbound traffic, average peak-hour traffic speeds would be mph, taking 34.2 seconds to cross the bridge. Since a three-lane section with no shoulder provides average speeds less than the posted speed limit over the bridge and increases travel time, the rating for this category is Negative. Level of Service (LOS): Using the HCM, the 2030 LOS for a three-lane section with no shoulders results in a density of 32.9 pc/mi/ln northbound and 40.8 pc/mi/ln southbound. Based on the criteria, these densities equate to a LOS D northbound and LOS E southbound. These conditions do not meet the AASHTO guidelines, which details a design LOS C as an acceptable threshold for peak-hour freeway flow. As a result of these operating conditions, the rating for this category is Negative. Capacity: With a base free-flow speed of 70 mph and a reduction of 3.0 mph for fewer than five lanes, and a reduction of 2.0 mph for lateral clearance/shoulder width less than 2 feet on the bridge, a freeflow speed of 65.0 mph is used on the bridge. This results in a capacity of 2,350 vehicles per hour (vph) per lane or 7,050 vph over the bridge. Since there is reduced capacity because of shoulder width, and no increased capacity to meet 2030 demands, the rating for this category is Negative. Right-of-Way Fee Taking: No fee takings are required for this alternative, so the rating is Positive. Permanent Easement: No permanent easements are required for this alternative, so the rating is Positive. Temporary/Construction Easement: No temporary/construction easements are required for this alternative, so the rating is Positive. 3-5

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7 Cost The existing highway alignment includes numerous bridge structures some reaching the end of their economic life and others in need of preservation programs to ensure cost-effective life cycle costs. The Whittier Bridge and I-95 over the Evans Place Bridge have reached the end of their economic life and require replacement. The other bridges within the study area I-95 over Route 110, I-95 over Railroad ROW, and the three northern bridges were constructed in the late 1960s with I-495 and are in need of bridge preservation and rehabilitation. The No Build Alternative would continue to require increasingly more costly repairs to keep the structures in full service, resulting in a Positive near-term rating but Negative long-term rating; consequently, the overall rating is Negative. Construction Utility Relocation: No existing municipal utilities would be affected by the No Build Alternative, and no utility relocations or reconstructions would be required; therefore, the No Build Alternative is rated Positive for this criterion. Constructability/Demolition of Existing Structure: The existing highway alignment includes numerous bridge structures some reaching the end of their economic life and others in need of preservation programs to ensure cost-effective life cycle costs. The Whittier Bridge and I-95 over the Evans Place Bridge have reached the end of their economic life and require replacement. The other bridges within the study area I-95 over Route 110, I-95 over Railroad ROW, and the three northern bridges were constructed in the late 1960s with I-495 and are in need of bridge preservation and rehabilitation. The No Build Alternative would continue to require increasingly more difficult repairs and constructability concerns to keep the structures in full service, resulting in a Negative near-term rating and long-term rating. Maintenance of Traffic: The No Build Alternative would require ongoing maintenance. Some maintenance operations would affect traffic with lane closures. The rating for this category is Negative. Schedule The existing highway alignment includes numerous bridge structures some reaching the end of their economic life and others in need of preservation programs to ensure cost-effective life cycle costs. For the No Build Alternative, as noted in the Cost description, increasing levels of repair would be required by these structures and each repair project would have schedule durations of some impact on the motoring public, resulting in a Positive near-term rating but a Negative long-term rating; consequently, the overall rating is Negative. Environmental Stormwater: The existing drainage infrastructure is assumed to provide a lower level of water quality treatment for existing stormwater discharges from the project relative to the overall water quality that could be provided through new drainage infrastructure that would be included under any of the Build Alternatives. Under the No Build Alternative, no changes to the existing stormwater drainage system would occur; therefore, this alternative is deemed Negative for this criterion. Drinking Water Quality: The No Build Alternative would not result in additional impervious surface or additional highway stormwater runoff within the Newburyport or Salisbury drinking water supply protection areas; however, no improvements to the stormwater-discharge water quality would be constructed. The No Build Alternative is rated Neutral for this criterion. Wetlands: The No Build Alternative would not result in any additional direct or indirect impacts to either coastal or inland wetland resources in the project corridor; however, several indirect impacts that are currently degrading wetlands would continue. One impact is to the salt marsh on the south side of the Merrimack River because of stormwater flow from a degraded 36-inch culvert on the east side of the highway. The flows bisect a salt marsh by scouring the peat and vegetation. Shading directly under the bridge has resulted in sparse, weedy vegetation in the coastal marshes and Bordering Vegetated Wetlands on the north side, and little vegetation on the south side. The other impacts are also stormwater related at Wetlands E and H where stormwater flows directly into the wetlands via a paved swale (Wetland E) and ditches (Wetland H) with little apparent treatment. Invasive plant species (purple loosestrife and Phragmites) at both wetlands benefit from these flows to the detriment of the native vegetation. The rating is Neutral for this criterion. Visual/View Points: The No Build Alternative would not result in any changes to the existing Whittier Bridge, nor would it result in constructing additional lanes to I-95 in the project corridor; therefore, it would not result in any change to the visual landscape. For this reason, this alternative was considered Positive for this criterion. Historic: The No Build Alternative would not result in demolishing or reconstructing the existing Whittier Bridge; therefore, this alternative is considered to be Positive. Navigation: The No Build Alternative would result in no temporary or permanent impacts to navigation on the Merrimack River, nor would there be any improvements to navigation. The rating is Neutral. Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Progressive Alternative) Conclusion for the No Build Alternative Pursuant to standard NEPA and MEPA practice, the No Build Alternative will be carried forward to the second-level screening analysis Progressive Alternative Under this staging scheme, the existing span/pier arrangement would be retained and the existing piers and superstructure progressively replaced with a new bridge. The pier locations for the Progressive Alternative are also shown in Figure 3-1. The proposed bridge would require six phases of construction: Phase I: New southbound bridge would be constructed just west of the existing structure, and once completed, the southbound traffic would be transferred to the new structure. Phase IIA: Install extensive temporary support girders under the floorbeams to temporarily support the main trusses in advance of the next phase. Stabilize pinned floorbeam connections in Spans 3, 4, and 5. Phase IIB: Existing southbound bridge would be demolished while traffic operates on the northbound side of structure. Phase IIC: New northbound bridge would be built over a portion of the existing old bridge footprint. Northbound traffic would be relocated to a new structure in its permanent operation. Phase III: Bridge would be widened to full width and traffic shifted to final alignment. Phase IV: Final demolition of the existing bridge. Purpose and Need The Progressive Alternative would result in constructing a new Merrimack River bridge crossing that would fully comply with current interstate highway design standards for lane and shoulder widths and would result in two additional travel lanes on I-95; therefore, this alternative would fully comply with the Purpose and Need of the project and is considered Positive for this criterion. Highway Configuration Horizontal Alignment: The bridge tangents for this alternative can be tied back into the existing baseline both north and south of the bridge (see Figure 3-2). The only deviation from the design requirements is that the large radius curves required on the north- and southbound barrel near the Evan s Place Bridge do not meet the MassDOT requirements for minimum length of curve (Figure 3-2, sheet 3). The impact of this deviation is minimal because of the large radii, so the rating is Neutral. 3-7

8

9 ZONE I

10

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12 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Progressive Alternative) Vertical Alignment: There are no issues with the vertical profile required for this alternative, so the rating is Positive. Impacts to Existing Infrastructure: The alignment required for the northand southbound barrels south of the bridge, to tie the bridge tangent back to the existing highway, would affect the Pine Hill/Ferry Road Bridge (Figure 3-2, sheet 2). This alternative would also affect the Route 110 eastbound to I-95 southbound on-ramp and the I-95 northbound to Route 110 eastbound off-ramp (Figure 3-2, sheet 4). Because of the number of impacts, the rating is Negative. Bridge Configuration The structural design attributes of the existing bridge, namely, the common center truss rib in Spans 3, 4, and 5 and the hinged floorbeam joint, have major limitations on maintaining the stability of the existing structure in a partially demolished condition during the progressive staged construction of the new bridge. Additionally, since many of the existing bridge main members have undergone short-term repairs and fixes that are of temporary nature, confirming the structural adequacy of the existing bridge members to carry existing traffic in this interim condition may be fairly complex, costly, and unreliable. The progressive staging scheme would be non-feasible because of the difficulty in performing the necessary repairs to the structure while it is carrying traffic. Constructing a temporary detour bridge, as outlined in Section , may be the only prudent course of action. Accordingly, this Progressive Alternative has Negative ratings for Design Standards/Complexities and Structural Safety and Neutral ratings for Hydraulics, Context-Sensitive Structure, Maintenance and Inspection, and Life Cycle/Cost. Traffic The Progressive Alternative would construct an eight-lane bridge with shoulders. The following criteria describe the impact the four-lane section in each direction would have on traffic conditions: Travel Time: Travel time depends on the speed of vehicles and the number of lane changes that occur for merging, weaving, and diverging conditions. In the northbound direction, the average peakhour speed would be mph, taking approximately 30.6 seconds to cross the bridge depending on span length. For southbound traffic, average peak-hour traffic speeds would be mph, taking approximately 30.7 seconds to cross the bridge. Since a four-lane section would improve travel times and speeds over the bridge, the rating for this category is Positive. Level of Service (LOS): Using the HCM, the 2030 LOS for a four-lane section with shoulders results in a density of 21.7 pc/mi/ln northbound and 24.6 pc/mi/ln southbound. Based on the HCM criteria, these densities both equate to a LOS C, which is a condition of stable flow and is considered acceptable for peak freeway flow. As a result of these operating conditions, the rating for this category is Positive. Capacity: With a base free-flow speed of 70 mph and a reduction of 1.5 mph for fewer than five lanes, a free-flow speed of 68.5 mph is used on the corridor. This results in a capacity of 2,385 vph per lane or 9,540 vph over the bridge. Based on improved capacity compared to No Build Alternative conditions, the rating for this category is Positive. Right-of-Way Similar to the No Build Alternative, no fee takings, no permanent easements, and no temporary/construction easements would be required for this alternative, so the rating is Positive in these three areas (See Section ). Cost The Progressive Alternative would involve a high level of cost and schedule risk costs because of the complexity of the staging, and the requirement to inspect, model, and analyze the existing structure for partial demolition under live load on the adjacent barrel of traffic. This uncertainty and associated interim strengthening costs and a meticulously planned demolition under active traffic from the adjacent barrel would create high costs with this element that would not be incorporated into the final project but would be staging and throw away costs, resulting in a Negative rating. Construction Utility Relocation: This alternative would result in reconstructing existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected. For these reasons, this alternative is judged to be Neutral. Constructability/Demolition of Existing Structures: The Progressive Alternative would involve an extreme level of constructability risk because of the complexity of the staging, and the requirement to inspect, model and analyze the existing structure for partial demolition under live load on the adjacent barrel of traffic. This uncertainty and associated interim strengthening scope and a meticulously planned demolition plan under active traffic from the adjacent barrel create severe constructability risk, limits ingenuity, and results in a high risk operation. This results in an unacceptable or Negative rating. Maintenance of Traffic: This alternative must be constructed in six stages, with detailed construction sequencing required. The northbound traffic in the third stage is located over the existing southbound barrel. This crossover is constructed in the second stage in the limited area between the relocated southbound traffic and existing northbound traffic. Due to these constraints, the rating for this category is Negative. Schedule The Progressive Alternative would involve a high level of schedule risk because of the complexity of the staging and the requirement to inspect, model and analyze the existing structure for partial demolition under live load on the adjacent barrel of traffic. This uncertainty and associated interim strengthening scope and a meticulously planned demolition plan under active traffic from the adjacent barrel create severe schedule risk, limit ingenuity, and results in a longer schedule. This results in a Negative rating. Environmental Stormwater: Substantial drainage infrastructure improvements would be required because of the revised southbound highway alignment, which would be located on the west side of the existing bridge. In Drainage Zone 1, there is an opportunity to locate a significant treatment BMP within the ROW, on the east side of the existing northbound corridor near the existing discharge to the Merrimack River. A benefit to locating a treatment BMP in this area is that it would be outside of any direct overland influence to Bartlett Spring Pond. In Drainage Zone 3, there are some limitations with respect to locating BMPs because of the existing topography and proximity of wetlands within the existing ROW. The new drainage infrastructure system would be designed to meet all the stormwater management standards defined as new development and that portion of the project that is defined as redevelopment would meet the stormwater standards as required to the maximum extent practical; therefore, the rating for this category is Neutral. Drinking Water Quality: This alternative is assumed to result in additional travel lanes on I-95 on the Newburyport approach to the new bridge, which would be constructed on the current bridge alignment. It is assumed that although the new travel lanes on I-95 would result in additional stormwater runoff into the existing highway drainage system, this criterion would only apply to the actual bridge crossing (highway widening is evaluated under the Highway Widening Alternatives later in this report); therefore, as it is assumed that stormwater runoff off the new bridge would be directed directly to the Merrimack River, there would be no additional stormwater discharge within any drinking water supply protection areas. This alternative is rated Neutral for this criterion. 3-12

13 Wetlands: Salt Marsh, Coastal Beach and Land Subject to Coastal Storm Flowage lie directly under the proposed bridge structure. This alternative would result in minor indirect impacts to wetland resource areas located on both banks of the Merrimack River from additional areas of shading, resulting from a wider new bridge structure, and permanent impacts to the river bottom resulting from the larger footprint of the existing bridge piers in the river. This alternative is rated Negative for this criterion. Visual/View Points: Since the Progressive Alternative would shift the bridge structure slightly to the west of the existing structure and would add additional lanes along I-95 in the project corridor, it would result in minor changes to the visual landscape. For this reason, this alternative is considered Neutral for this criterion. Historic: This alternative would alter the existing Whittier Bridge through progressively demolishing the existing bridge; therefore, this alternative is considered Negative for this criterion. Navigation: As noted in other sections, this alternative, because of the complexity of the staging and construction, would result in a longer schedule, thereby requiring equipment in the waterway for longer periods of time. The Progressive Alternative would not reduce existing vertical or horizontal clearance. There would be no long-term adverse impacts to navigation; however, the extended construction duration would have greater potential for impacts to navigation. This results in a Negative rating. Conclusion for the Progressive Staging Alternative Due to the significance of the Negative ratings for several criteria related to the design and structural safety of the bridge, as well as Negative ratings for the construction factors involving constructability and maintenance of traffic during construction, the Progressive Staging alternative will not move forward to the second screening analysis Rehabilitation Alternative Under this scheme, because of the extensive deterioration for the existing structure as identified in the inspection reports, the temporary nature of the near-term repairs, and the indeterminate nature of much of the structure, the existing bridge would need to undergo a major rehabilitation. The rehabilitation would require a temporary bridge to remove all traffic from the existing structure to support the rehabilitation. The pier locations for the Rehabilitation Alternative are also shown on Figure 3-1. Purpose and Need The Rehabilitation Alternative would not result in any geometric changes to the existing Whittier Bridge; therefore, no safety improvements or capacity improvements would be constructed. For these reasons, this alternative was rated Negative for this criterion. Highway Configuration Horizontal Alignment: This alternative would maintain the existing horizontal alignment. This alternative would not provide for the desired shoulder widths. The rating for this category is Negative. Vertical Alignment: This alternative would maintain the existing vertical alignment. The rating for this category is Positive. Impacts to Existing Infrastructure: No impacts to existing infrastructure are expected. The rating for this category is Positive. Bridge Configuration The Rehabilitation Alternative would involve replacing all the deck, stringers, floorbeams, most of the bracing, gusset plates, wire rope hangers, and expansion joints. Any truss-member gusset-plate connections identified as being deficient, as a result of the load rating analysis that is currently in progress, would also need to be replaced. Other truss members and connections may need to be replaced or strengthened based on the results of a fatigue life analysis, and deficiencies such as extensive pack rust and section loss. The existing footings at Piers 1, 2, 3, and 4 do not meet code requirements, as they are unreinforced concrete. These footings are non-ductile (inflexible) and could fail when subjected to an overload condition such as an earthquake. A preferred long-term solution would be to completely replace the piers, which would provide greatly enhanced safety for regular and seismic loads. Additionally, as a result of the common center-truss rib in Spans 3, 4 and 5 and the hinged floorbeam joint, to safely replace the deck members and wire rope hangers during rehabilitation, a temporary detour bridge would be constructed to remove all traffic from the existing bridge; therefore, it is not considered feasible to undergo the major bridge rehabilitation stated above while the bridge is carrying traffic. Accordingly, with the exception of Hydraulics and Context-Sensitive Structure, which have Neutral ratings, this alternative has Negative ratings for all remaining four Bridge Configurations subcategories: Design Standards/ Complexities, Structural Safety, Maintenance and Inspection, and Life Cycle/Cost. Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Rehabilitation Alternative) Traffic Rehabilitating the existing bridge would maintain the existing bridge cross section of six lanes with no shoulders, similar to the No Build Alternative., Under this alternative, the three traffic categories of Travel Time, Level of Service (LOS), and Capacity have all been rated Negative (see Section ). Right-of-Way Similar to the No Build Alternative, no Fee Takings, no Permanent Easements, and no Temporary/Construction Easements would be required for the Rehabilitation Alternative, so the rating is Positive in these three areas (see Section ). Cost The Rehabilitation Alternative would involve a high level of cost and schedule risk because of the complexity and requirement to inspect, model, and analyze the existing structure to completely rehabilitate the unloaded structure. The indeterminate nature of some of the built up members and connections, and the required interim support in place of the skeletal frame of the structure and a meticulously planned memberby-member rehabilitation would result in a very inefficient and costly program. This results in a Negative rating. Construction Utility Relocation: No existing municipal utilities would be affected by the Rehabilitation Alternative and no utility relocations or reconstructions would be required; therefore, the Rehabilitation Alternative is rated Positive for this criterion. Constructability/Demolition of Existing Structures: The Rehabilitation Alternative would involve extended work durations and a high level of constructability risk because of the complexity and requirement to inspect, model, and analyze the existing structure to completely rehabilitate the unloaded structure. The indeterminate nature of some of the built up members and connections, and required interim supporting in place of the skeletal frame of the structure and a meticulously planned member-bymember rehabilitation would result in a very inefficient and labor intensive program. This results in a Negative rating. Maintenance of Traffic: Maintaining traffic on the existing bridge while it is rehabilitated would be difficult. A temporary bridge would be required. The rating for this category is Negative. 3-13

14 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Retrofit with Adjacent Structure Alternative) Schedule The Rehabilitation Alternative would involve extended work durations and a high level of schedule risk because of the complexity and requirement to inspect, model, and analyze the existing structure to completely rehabilitate the unloaded structure. The indeterminate nature of some of the built up members and connections, and required interim supporting in place of the skeletal frame of the structure and a meticulously planned member-by-member rehabilitation would result in a very inefficient and labor intensive program. This results in a Negative rating. Environmental Stormwater: The existing stormwater infrastructure would remain primarily unimproved under this alternative, which would be similar to the No Build Alternative; therefore, this alternative is considered Negative for this criterion. Drinking Water Quality: The Rehabilitation Alternative would not result in additional impervious surface or additional highway stormwater runoff within the Newburyport or Salisbury drinking water supply protection areas, similar to the No Build Alternative (see Section ). However, no improvements to the stormwater-discharge water quality would be constructed. The Rehabilitation Alternative is rated Neutral for this criterion. Wetlands: The Rehabilitation Alternative would not result in any additional direct or indirect permanent impacts to either coastal or inland wetland resources at the Merrimack River; therefore, the Rehabilitation Alternative is rated Positive for this criterion. Visual/View Points: The Rehabilitation Alternative would not result in any geometric changes to the existing Whittier Bridge; therefore, this alternative would result in no change to the visual landscape. For this reason, this alternative is given a Positive rating for this criterion. Historic: The Rehabilitation Alternative would not demolish or alter the historic appearance of the existing Whittier Bridge; therefore, this alternative is considered Positive for this criterion. Navigation: This alternative would result in a longer schedule because of the complexity of construction, thereby requiring equipment in the waterway for longer periods of time. The alternative would not result in a reduction of existing vertical or horizontal clearance but would result in potential longer-term impacts related to construction. There would be no long-term adverse impacts to navigation; however, the extended construction duration would have greater potential for impacts to navigation. This results in a Negative rating. Conclusion for the Rehabilitation Alternative Because of the large number of Negative ratings, particularly those associated with Bridge Configuration, Construction, and Schedule issues, the Rehabilitation Alternative will not be carried forward to the second-level screening analysis Retrofit with Adjacent Structure Alternative This scheme is identical to the Rehabilitation Alternative of Section , with the understanding that a six-lane temporary detour bridge would be needed to carry all existing traffic. Purpose and Need The Retrofit with Adjacent Structure Alternative would construct new or rehabilitated Merrimack River bridges that would fully comply with current interstate highway design standards for lane and shoulder widths and would result in two additional travel lanes on I-95; therefore, this alternative would fully comply with the Purpose and Need of the project and is rated Positive for this criterion. Highway Configuration Horizontal Alignment: The bridge tangents for this alternative would be tied back into the existing baseline both north and south of the bridge. The geometry of the proposed highway would be substandard because to use the existing bridge for four southbound lanes, two lanes would have to be located on either side of the existing center trusses creating a safety issue. For this reason, the rating for this category is Negative. Vertical Alignment: This alternative would maintain the existing vertical alignment. The rating for this category is Positive. Impacts to Existing Infrastructure: The alignments required for this alternative would be designed to avoid affecting the Pine Hill/Ferry Road Bridge if the design speed for the temporary alignments could be reduced to 65 mph, and direct curve-to-tangent transitions would be allowed. This alternative would affect the I-95 northbound to Route 110 eastbound offramp. The rating for this category is Neutral. Bridge Configuration With almost all design and construction attributes in common with the Rehabilitation Alternative, ratings are the same for this Retrofit with Adjacent Structure Alternative. Accordingly, with the exception of Hydraulics and Context-Sensitive Structure, which have Neutral ratings, this alternative has Negative ratings for all remaining four Bridge Configurations subcategories: Design Standards/Complexities, Structural Safety, Maintenance and Inspection, and Life Cycle/Cost. Traffic Retrofitting the existing bridge with an adjacent structure would maintain the existing bridge cross section of six lanes with no shoulders, similar to the No Build Alternative. Under this alternative, the three traffic categories of Travel Time, Level of Service (LOS), and Capacity have all been rated Negative (see Section ). Right-of-Way Fee Taking: No fee takings would be required for this alternative. The rating for this category is Positive. Permanent Easement: A permanent easement to maintain the retaining walls north and south of the bridge crossing would be required, resulting in a Neutral rating. Temporary/Construction Easement: The proximity of the northbound barrel to the east side of the ROW would necessitate acquiring temporary easements to facilitate constructing retaining walls both north and south of the river. The rating for this category is Negative. Cost The Retrofit with Adjacent Structure Alternative would involve a high level of cost and schedule risk costs because of the complexity and requirement to inspect, model, and analyze the existing structure to completely rehabilitate the unloaded structure. For reasons similarly associated with the Rehabilitation Alternative, this results in a Negative rating (see Section ). Construction Utility Relocation: This alternative would reconstruct existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities would be expected. For these reasons, this alternative is judged Neutral. Constructability/Demolition of Existing Structures: The Retrofit with Adjacent Structure Alternative would involve the straightforward construction of a new parallel structure wide enough to remove all traffic from the existing bridge to provide a complete rehabilitation for a retrofit configuration. The rehabilitation portion would involve extended work durations and a high level of constructability risk because of the complexity and requirement to inspect, model, and analyze the existing structure to completely rehabilitate the unloaded structure. The 3-14

15 indeterminate nature of some of the built up members and connections and required interim supporting in place of the skeletal frame of the structure and a meticulously planned member-by-member rehabilitation would result in a very inefficient and labor intensive program. This results in a Negative rating. Maintenance of Traffic: The bridge staging for this alternative would require that traffic remain in place while the northbound bridge is constructed. Both north- and southbound traffic would then be diverted to the northbound bridge on temporary alignments while the existing bridge is retrofitted for four lanes of southbound traffic. Once that is completed, traffic would be diverted again to the final alignments. During the second stage, the southbound traffic would be forced to cross the existing northbound lanes to reach the temporary alignment on the northbound bridge, necessitating the development of detailed construction sequencing. The temporary alignments required could be designed to meet the design requirements for 70 mph, with the exception of the stopping sight distance for the left-most southbound lane at the existing Pine Hill/Ferry Road Bridge pier. With the existing Pine Hill/Ferry Road Bridge in place, the sight distance would meet a 65 mph design. In addition, to maintain the Pine Hill/Ferry Road Bridge the MassDOT requirement for the smallest curve radius without a transition would have to be relaxed for the temporary alignments to allow for direct tangent-tocurve transitions. The rating for this category is Neutral. Schedule The Retrofit with Adjacent Structure Alternative would involve extended work durations and a high level of schedule risk because of the complexity and requirement to inspect, model, and analyze the existing structure to completely rehabilitate the unloaded structure. For reasons similarly associated with the Rehabilitation Alternative, this results in a Negative rating (see Section ). Environmental Stormwater: The existing drainage infrastructure is assumed to provide a lower level of water quality treatment for existing stormwater discharges from the project relative to overall water quality than could be provided through new drainage infrastructure, which would be included under any of the Build Alternatives. Under the Retrofit with Adjacent Structure Alternative, some improvements to the existing stormwater drainage system would occur, but to a much more limited extent than would be provided under other Build Alternatives; therefore, this alternative is deemed Neutral. Drinking Water Quality: The Retrofit with Adjacent Structure Alternative would not result in additional impervious surface or additional highway stormwater runoff within the Newburyport or Salisbury drinking water supply protection areas, similar to the No Build Alternative (see Section ). The Retrofit with Adjacent Structure Alternative is rated Neutral for this criterion. Wetlands: Salt Marsh, Coastal Beach and Land Subject to Coastal Storm Flowage lie directly under the proposed bridge structure. The Retrofit with Adjacent Structure Alternative would result in minor indirect impacts to wetland resource areas, similar to the Progressive Alternative (see Section ). This alternative is rated Negative for this criterion. Visual: The Retrofit with Adjacent Structure Alternative would not demolish or alter the existing Whittier Bridge, and, thus, would not result in any change to the visual landscape; therefore, this alternative is rated Positive for this criterion. Historic: The Retrofit with Adjacent Structure Alternative would alter the historic setting of the existing Whittier Bridge by constructing a new bridge adjacent to the existing bridge. The existing bridge is assumed to remain with its existing historic features unchanged. This alternative is rated Neutral for this criterion. Navigation: This alternative would result in a longer schedule because of the complexity of construction, thereby requiring equipment in the waterway for longer periods of time. The alternative would not result in a reduction of existing vertical or horizontal clearance but would result in potential longer-term impacts related to construction. There would be no long-term adverse impacts to navigation; however, the extended construction duration would have greater potential for impacts to navigation. This results in a Negative rating. Conclusion for the Retrofit with Adjacent Structure Alternative Due to the large number of Negative ratings, particularly those associated with Bridge Configuration, Construction, and Schedule issues, the Retrofit with Adjacent Structure Alternative will not be carried forward to the second-level screening analysis New 6-Lane Bridge Alternative Under this staging scheme, two new bridges would be constructed, with each bridge carrying three lanes of traffic in either the northbound or the southbound directions in the final built condition. The new bridges would be constructed using the same staging schemes described in Sections Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( New 6-Lane Bridge Alternative) , , and for a new eight-lane bridge: East-West, East, and West. The two new three-lane bridges would have the same hydraulic and safety constraints as the four-lane bridges. For the East-West staging scheme, both bridges would be narrower than the two 4-lane bridges described in Section As for the East and West staging schemes, the first bridge would still have to accommodate six traffic lanes in the interim condition, while the second bridge would be narrower as it would only accommodate three traffic lanes. Each of the new three-lane bridges could also be constructed using the Progressive Alternative s staging scheme outlined in Section It would have the same number of phases but the completed bridge would eventually be narrower as it would carry only six traffic lanes for the northbound and southbound directions. Purpose and Need The New 6-Lane Bridge Alternative is assumed to include constructing additional width for travel lanes and shoulders to meet current geometric standards and, therefore, would result in safer operating conditions on the bridge; however, no capacity improvements would be constructed, and this alternative would not fully meet the Purpose and Need. For these reasons, this alternative is rated Negative for this criterion. Highway Configuration Horizontal Alignment: The bridge tangents for this alternative could be tied back into the existing baseline both north and south of the bridge. The only deviation from the design requirements would be that the large radius curve required on the southbound barrel near the I-95 Bridge over Evan s Place would not meet the MassDOT requirements for minimum length of curve. The impact of this deviation would be minimal because of the large radius. The rating for this category is Neutral. Vertical Alignment: There would be no issues with the vertical profile required for this alternative. The rating for this category is Positive. Impacts to Existing Infrastructure: The alignment required for the southbound barrel south of the bridge, to tie the proposed bridge tangent back to the existing highway, would affect the Pine Hill/Ferry Road Bridge. This alternative would also affect the Route 110 eastbound to I-95 southbound on-ramp and the I-95 northbound to Route 110 eastbound off-ramp. The rating for this category is Negative. Bridge Configuration With the exception of Hydraulics, which has a Neutral rating, the New 6- Lane Bridge Alternative has Positive ratings for the remaining five Bridge Configuration subcategories: Design Standards/Complexities, Structural 3-15

16 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( New 6-Lane Bridge Alternative) Safety, Context-Sensitive Structure, Maintenance and Inspection, and Life Cycle/Cost. Traffic Building a new six-lane bridge would maintain the existing three lanes in each direction, and would allow for the construction of adequate shoulders on the bridge. The following criteria describe the impact that the three-lane section in each direction with shoulders would have on traffic conditions: Travel Time: Travel time depends on the speed of vehicles and the number of lane changes that occur for merging, weaving, and diverging conditions. In the northbound direction, the average peakhour traffic speeds would be mph, taking 33.5 seconds to cross the bridge. For southbound traffic, average peak-hour traffic speeds would be mph, taking 33.4 seconds to cross the bridge. Since a three-lane section with shoulders would not significantly improve travel time and speed over the bridge, the rating for this category is Negative. Level of Service (LOS): Using the HCM, the 2030 LOS for a three-lane section with no shoulders results in a density of 31.2 pc/mi/ln northbound and 38.7 pc/mi/ln southbound. Based on the HCM criteria, these densities equate to a LOS D northbound and LOS E southbound. These conditions do not meet the guidelines of LOS C as an acceptable threshold for peak-hour freeway flow. As a result of these operating conditions, the rating for this category is Negative. Capacity: With a base free-flow speed of 70 mph and a reduction of 3.0 mph for fewer than five lanes, a free-flow speed of 67.0 mph is used on the bridge, resulting in a capacity of 2,370 vph per lane or 7,110 vph over the bridge. Since there would be no significant increase in capacity, the rating for this category is Negative. Right-of-Way Fee Taking: Constructing a narrower three-lane bridge would not affect the existing ROW. The rating for this category is Positive. Permanent Easement: A permanent easement would be required to maintain the retaining wall on the southbound approach to the bridge. The rating for this category is Negative Temporary/Construction Easement: Constructing the retaining walls would require temporary easements for construction and access. The rating for this category is Negative. Cost The New 6-Lane Bridge Alternative would involve a straightforward construction of new parallel structures adjacent to the existing bridge. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would ultimately complicate the demolition of the existing bridge because of the proximity of the new in-service bridges on either side of the existing bridge. This would necessitate demolishing the existing bridge from the opposing shores, and ultimately removing the southern approach trusses and allowing a marine crane to be mobilized to dismantle the existing bridge in a reverse manner of its original construction. This would introduce additional cost because of the restrained and inefficient manner of the demolition. In addition, a high level of cost and schedule risk costs would be introduced because of the complexity and safety requirements for safe demolition adjacent to the new bridges. The indeterminate nature of some of the built up members and connections, and the required interim supporting in place of the skeletal frame of the structure would result in an inefficient and costly program; therefore, the rating is Negative. Construction Utility Relocation: This alternative would reconstruct existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected; therefore, this alternative is judged Neutral. Constructability/Demolition of Existing Structure: The New 6-Lane Bridge Alternative would involve a straightforward construction of new parallel structures adjacent to the existing bridge. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would ultimately complicate the constructability/demolition of the existing bridge because of the proximity of the new in-service bridges on either side of the existing bridge. This would necessitate demolishing the existing bridge from the opposing shores, and ultimately removing the southern approach trusses and allowing a marine crane to be mobilized to dismantle the existing bridge in a reverse manner of its original construction. This would introduce additional constructability/demolition controls because of the restrained and inefficient manner of the demolition. In addition, a high level of constructability/demolition risk would be introduced because of the complexity and safety requirements for safe demolition adjacent to the new bridges. The indeterminate nature of some of the built up members and connections, and the required interim supporting in place of the skeletal frame of the structure would result in an inefficient program. This results in a Negative rating. Maintenance of Traffic: This alternative would construct the bridges and most of the new highway without disrupting the existing traffic. No temporary alignments would be required. The rating for this category is Positive. Schedule The New 6-Lane Bridge Alternative would involve a straightforward construction of new parallel structures adjacent to the existing bridge. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would ultimately complicate demolishing the existing bridge because of the proximity of the new in-service bridges on either side of the existing bridge. This would necessitate demolishing the existing bridge from the opposing shores, ultimately removing the southern approach trusses and mobilizing a marine crane to dismantle the existing bridge in a reverse manner of its original construction. This would introduce additional schedule duration because of the restrained and inefficient manner of the demolition. In addition, a high level of schedule risks would be introduced because of the complexity and safety requirements for safe demolition adjacent to the new bridges. The indeterminate nature of some of the built up members and connections, and the required interim supporting in place of the skeletal frame of the structure would result in an inefficient program. This results in a Negative rating. Environmental Stormwater: The existing drainage infrastructure is assumed to provide a lower level of water quality treatment for existing stormwater discharges from the project relative to the overall water quality that could be provided through new drainage infrastructure, which would be included under any of the Build Alternatives. Under the New 6-Lane Bridge Alternative, some improvements to the existing stormwater drainage system would occur; therefore, this alternative is deemed Neutral. Drinking Water Quality: The New 6-Lane Bridge Alternative would not result in additional impervious surface or additional highway stormwater runoff within the Newburyport or Salisbury drinking water supply protection areas, similar to the No Build Alternative (see Section ). However, no improvements to the stormwater-discharge water quality would be constructed. The New 6-Lane Bridge Alternative is considered Neutral for this criterion. 3-16

17 Wetlands: Salt Marsh, Coastal Beach and Land Subject to Coastal Storm Flowage lie directly under the proposed bridge structure. This alternative would result in minor indirect impacts to wetland resource areas, similar to the Progressive Alternative (see Section ). This alternative is rated Negative for this criterion. Visual/View Points: The New 6-Lane Bridge Alternative would replace the existing Whittier Bridge with two new bridges. Given that there would be two parallel bridge structures and at the same elevation, and depending on the method selected for staging of construction, as described above, this alternative could result in minor changes to the visual landscape. For this reason, this alternative is considered Neutral for this criterion. Historic: This alternative would demolish the existing Whittier Bridge; therefore, this alternative is rated Negative for this criterion. Navigation: As noted in other sections, the demolition of the existing bridge to be performed after the construction of new bridges on each side would be a complicated process. This alternative would result in comparatively greater potential for negative impacts to navigation during the construction/demolition phase because of the longer and more complicated demolition of the existing Whittier Bridge. The new bridge structures would have no negative permanent impacts to navigation. Because of the greater potential for impacts to navigation during construction/demolition, this alternative is rated Negative. Conclusion for the New 6-Lane Bridge Alternative Because the New 6-Lane Bridge Alternative does not meet the Purpose and Need, and because of the large number of Negative ratings for factors associated with Traffic, ROW, Constructability, and Schedule, this alternative will not be carried forward into the second-level screening analysis New 8-Lane East West Bridge Alternative Under this staging scheme, two new bridges would be constructed simultaneously on the east and west side of the existing bridge. The pier locations for the 8-Lane East West Alternative are shown in Figure 3-3. The east and west roadways would each carry four lanes of northbound and southbound traffic, respectively. Once completed, all existing traffic on I-95 would be immediately relocated to the two new bridges and the existing truss spans would be demolished free of traffic. Purpose and Need The New 8-Lane East West Bridge Alternative would construct a new Merrimack River bridge crossing, which would fully comply with current interstate highway design standards for lane and shoulder widths and would result in two additional travel lanes on I-95; therefore, this alternative would fully comply with the Purpose and Need of the project and is given a Positive rating for this criterion. Highway Configuration Horizontal Alignment: The bridge tangents for this alternative would be tied back into the existing baseline both north and south of the bridge ( Figure 3-4). The only deviation from the design requirements would be that the large radius curve required on the southbound barrel near the Evan s Place Bridge would not meet the MassDOT requirements for minimum length of curve (Figure 3-4, sheet 3). The impact of this deviation would be minimal because of the large radius. The rating for this category is Neutral. Vertical Alignment: There would be no issues with the vertical profile required for this alternative. The rating for this category is Positive. Impacts to Existing Infrastructure: The alignment required for the southbound barrel south of the bridge, to tie the proposed bridge tangent back to the existing highway, would affect the Pine Hill/Ferry Road Bridge (Figure 3-4, sheet 2). This alternative would also affect the Route 110 eastbound to I-95 southbound on-ramp and the I-95 northbound to Route 110 eastbound off-ramp (Figure 3-4, sheet 4). The rating for this category is Negative. Bridge Configuration Demolition and removal of the existing truss spans located between the two new bridges could prove to be a challenging task. Such demolition would likely involve limited or restricted access to perform the work, in addition to staging and construction complexities associated with ensuring safety of the new structure while maintaining the safety and stability of the existing structure at every stage of the demolition and removal. Accordingly, with the exception of Design Standards/Complexities and Hydraulics, which are Neutral ratings, this alternative has Positive ratings for the remaining four Bridge Configuration subcategories: Structural Safety, Context-Sensitive Structure, Maintenance and Inspection, and Life Cycle/Cost. Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( New 8-Lane East West Bridge Alternative) Traffic The New 8-Lane East West Bridge Alternative would construct four lanes in each direction with shoulders on the bridge, similar to the Progressive Alternative. Under this alternative, the three traffic categories of Travel Time, Level of Service (LOS), and Capacity have all been rated Positive (see Section ). Right-of-Way Fee Taking: The proposed southbound bridge location, west of the existing bridge, would force the southbound barrel north of the bridge to affect the ROW, requiring a fee taking ( Figure 3-4, sheet 3). The rating for this category is Negative. Permanent Easement: Even with the fee taking, a permanent easement would likely be required for maintenance of the retaining wall needed at the edge of the proposed ROW line. The rating for this category is Negative. Temporary/Construction Easement: Constructing the retaining walls would require temporary easements for construction and access. The rating for this category is Negative. Cost The New 8-Lane East West Bridge Alternative would involve a straightforward construction of new parallel structures adjacent to the existing bridge. The construction would be uncomplicated by site constraints, and the subsequent demolishing of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would ultimately complicate the demolition of the existing bridge because of the proximity of the new in-service bridges on either side of the existing bridge. This would necessitate demolishing the existing bridge from the opposite shores, ultimately removing the southern approach trusses and mobilizing a marine crane to dismantle the existing bridge in a reverse manner of its original construction. This would introduce additional cost because of the restrained and inefficient manner of the demolition. In addition, a high level of cost and schedule risk costs would be introduced because of the complexity and safety requirements for safe demolition adjacent to the new bridges. The indeterminate nature of some of the built up members and connections, and the required interim supporting in place of the skeletal frame of the structure would result in an inefficient and costly program. This results in a Negative rating. 3-17

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23 Construction Utility Relocation: This alternative would result in the reconstruction of existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected. For these reasons, this alternative is judged Neutral. Constructability/Demolition of Existing Structure: The New 8-Lane East West Bridge Alternative would involve a straightforward construction of new parallel structures adjacent to the existing bridge. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would ultimately complicate the constructability/demolition of the existing bridge because of the proximity of the new in-service bridges on either side of the existing bridge. This would necessitate the demolition of the existing bridge from the opposing shores, ultimately removing the southern approach trusses and allowing a marine crane to be mobilized to dismantle the existing bridge in a reverse manner of its original construction. This would introduce additional constructability/demolition controls because of the restrained and inefficient manner of the demolition. In addition, a high level of constructability/demolition risk would be introduced because of the complexity and safety requirements for safe demolition adjacent to the new bridges. The indeterminate nature of some of the built up members and connections, and the required interim supporting in place of the skeletal frame of the structure, would result in an inefficient program. This results in a Negative rating. Maintenance of Traffic: This alternative would construct the bridges and most of the new highway without disrupting the existing traffic. No temporary alignments would be required. The rating for this category is Positive. Schedule The New 8-Lane East West Bridge Alternative would construct new parallel structures adjacent to the existing bridge. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would ultimately complicate the demolition of the existing bridge because of the proximity of the new in-service bridges on either side of the existing bridge. This would necessitate the demolition of the existing bridge from the opposite shores, ultimately removing the southern approach trusses and allowing a marine crane to be mobilized to dismantle the existing bridge in a reverse manner of its original construction. This would introduce additional schedule duration because of the restrained and inefficient manner of the demolition. In addition, a high level of schedule risks would be introduced because of the complexity and safety requirements for safe demolition adjacent to the new bridges. The indeterminate nature of some of the built up members and connections, and the required interim supporting in place of the skeletal frame of the structure would result in an inefficient program. This results in a Negative rating. Environmental Stormwater: Substantial drainage infrastructure improvements would be required as a result of the new highway alignments. The New 8-Lane East West Bridge Alternative presents an opportunity to locate stormwater BMPs in the newly created median between the new northbound and southbound corridors; however, management of stormwater during construction, prior to project completion, would be difficult. With respect to Drainage Zone I, to comply with Standard 6 (critical area), a higher level of pre-treatment would have to be provided prior to discharge into an infiltration basin, which could be located within the Water Resource Zone B/Zone II. This alternative is given a Positive rating for this criterion. Drinking Water Quality: This alternative would result in additional impervious surface area resulting from realignment and widening of the I-95 southbound lanes immediately south of the Merrimack River, resulting in new impervious surface within 400 feet of Bartlett Springs Pond; therefore, this alternative is rated Negative for this criterion. Wetlands: Salt Marsh, Rocky Intertidal Shore and Land Subject to Coastal Storm Flowage lie directly under the proposed East and West bridge spans, although no direct impacts would occur to these resources. The amount of Coastal Beach under the bridge could be reduced in this alternative because of the narrowing wetland on the west side. Potential indirect impacts from shading should be minimal because: 1) the proposed bridges would be higher than the existing bridge; 2) there would be two spans with a gap of approximately 105 feet between them; and 3) the abutment would be set further from the river. This configuration would allow considerably more light under the bridge than currently occurs. This alternative is rated Neutral for this criterion. Visual/View Points: Under this alternative, the two new bridge structures would be wider than the existing structure and slightly closer to adjacent uses. This alternative would have a negative impact on the condominium residences adjacent to the east and west of the bridge. This alternative is given a Negative rating for this criterion. Historic: This alternative would demolish the existing Whittier Bridge; therefore, this alternative is rated Negative for this criterion. Navigation: As noted in other sections, the demolition of the existing bridge to be performed after the construction of new bridges on each side Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( New 8-Lane East Bridge Alternative) would be a complicated process. This alternative would result in comparatively greater potential for negative impacts to navigation during the construction/demolition phase because of the longer and more complicated demolition of the existing Whittier Bridge. The new bridge structures would have no negative permanent impacts to navigation. Because of the greater potential for impacts to navigation during construction/demolition, this alternative is rated Negative. Conclusion for the 8-Lane East West Bridge Alternative The New 8 Lane East West Bridge Alternative will not be carried forward to the second-level screening analysis because of the high number of Negative rankings related to Impacts to Existing Infrastructure, ROW, Constructability, Schedule, and several environmental criteria, in particular proximity to the Newburyport public surface water supply New 8-Lane East Bridge Alternative Under this staging scheme, a new bridge would be constructed on the east side of the existing bridge so that upon completion, all six lanes of traffic on I-95 would be immediately relocated to the new bridge, thus permitting the existing truss spans to be demolished free of traffic and in one phase. The new I-95 southbound carrying four lanes of traffic would be built in the new space provided. Once opened to traffic, the I-95 northbound bridge would be reconfigured for the four lanes and necessary shoulders on each side of the travel lanes. The pier locations for the New 8-Lane East Bridge Alternative are shown on Figure 3-5. Purpose and Need The New 8-Lane East Bridge Alternative would construct a new Merrimack River bridge crossing, which would fully comply with current interstate highway design standards for lane and shoulder widths and would result in two additional travel lanes on I-95; therefore, this alternative would fully comply with the Purpose and Need of the project and is rated Positive for this criterion. Highway Configuration Horizontal Alignment: The bridge tangents for this alternative would be tied back into the existing baseline both north and south of the bridge (see Figure 3-6). The length of the project would be extended approximately 1,600 feet to the south in order for the proposed alignment to avoid the existing Pine Hill/Ferry Road Bridge, meet all of the compound curvature requirements, and tie into the proposed bridge tangent (Figure 3-6, sheet 1). All design requirements would be met. The rating for this category is Neutral. 3-23

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29 Vertical Alignment: There would be no issues with the vertical profile required for this alternative. The rating for this category is Positive. Impacts to Existing Infrastructure: The alignments required for this alternative would be designed to avoid affecting the Pine Hill/Ferry Road Bridge if the design speed for the temporary alignments could be reduced to 65 mph and direct curve--to tangent transitions allowed. Avoiding the Pine Hill/Ferry Road Bridge would also lengthen the project approximately 1,600 feet to the south. This alternative would affect the Route 110 eastbound to I-95 southbound on-ramp and the I-95 northbound to Route 110 eastbound off-ramp. The rating for this category is Neutral. Bridge Configuration With the exception of Hydraulics, which is given a Neutral rating, this alternative has Positive ratings for all remaining five Bridge Configurations subcategories: Design Standards/Complexities, Structural Safety, Context- Sensitive Structure, Maintenance and Inspection, and Life Cycle/Cost. Traffic The New 8-lane East Alternative would construct four lanes in each direction with shoulders on the bridge, similar to the Progressive Alternative. Under this alternative, the three traffic categories of Travel Time, Level of Service (LOS), and Capacity have all been rated Positive (see Section ). Right-of-Way Fee Taking: No fee takings would be required for this alternative. The rating for this category is Positive. Permanent Easement: A permanent easement, to maintain the retaining walls north and south of the bridge crossing would be required (Figure 3-6, sheets 2 and 3). The rating for this category is Negative. Temporary/Construction Easement: The proximity of the northbound barrel to the east side of the ROW would require temporary easements to be acquired to facilitate constructing retaining walls both north and south of the river (Figure 3-6, sheet 2). The rating for this category is Negative. Cost The New 8-Lane East Bridge Alternative would involve a straightforward construction of a new parallel northbound over-width structure adjacent to the existing bridge, transfer of all traffic off the existing structure and subsequent construction of the new southbound span, transfer of southbound traffic, and final reconfiguration of the northbound span. The construction would be uncomplicated by site constraints, and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would allow full crane access from the west side of the existing bridge. This would simplify demolishing the southern approach truss and subsequent dismantling of the existing main span bridge in a reverse manner of its original construction. Once the existing structure is complete, the bridge construction team would be remobilized to complete the construction of the new southbound span. This results in a Positive rating. Construction Utility Relocation: This alternative would reconstruct existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected. For these reasons, this alternative is considered Neutral. Constructability/Demolition of Existing Structures: The New 8-Lane East Bridge Alternative would involve a straightforward construction of a new parallel northbound over-width structure adjacent to the existing bridge, transfer of all traffic off the existing structure, and subsequent construction of the new southbound span, transfer of southbound traffic and final reconfiguration of the northbound span. This alternative would provide for the earliest removal of traffic from the existing structure. The construction would be uncomplicated by site constraints, and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would allow full crane access from the west side of the existing bridge. This would simplify demolishing the southern approach truss and subsequent dismantling of the existing main span bridge in a reverse manner of its original construction resulting in a safer operation. Once the existing structure is complete, the bridge construction team would remobilize to complete the construction of the new southbound span. This results in a Positive rating. Maintenance of Traffic: The bridge staging for this alternative would require that traffic remain in place while the northbound bridge is constructed. Both north- and southbound traffic would then be diverted to the northbound bridge on temporary alignments while the existing bridge is demolished and the new southbound bridge is constructed. Once completed, traffic would be diverted again to the final alignments. During the second stage, the southbound traffic would be forced to cross the existing northbound lanes to reach the temporary alignment on the northbound bridge, necessitating the development of detailed construction sequencing. The temporary alignments required could be designed to meet the design requirements for 70 mph, with the exception Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( New 8-Lane East Bridge Alternative) of the stopping sight distance for the left-most southbound lane at the existing Pine Hill/Ferry Road Bridge pier. With the existing Pine Hill/Ferry Road Bridge in place, the sight distance would meet a 65 mph design. In addition, to maintain the Pine Hill/Ferry Road Bridge, the MassDOT requirement for the smallest curve radius without a transition would have to be relaxed for the temporary alignments to allow for direct tangent-tocurve transitions. The rating for this category is Neutral. Schedule The New 8-Lane East Bridge Alternative would involve a straightforward construction of a new parallel northbound over-width structure adjacent to the existing bridge, transfer of all traffic off the existing structure and subsequent construction of the new southbound span, transfer of southbound traffic and final reconfiguration of the northbound span. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would allow full crane access from the west side of the existing bridge. This would simplify the demolition of the southern approach truss and subsequent dismantling of the existing main span bridge in a reverse manner of its original construction. Once the existing structure is complete, the bridge construction team would remobilize to complete the construction of the new southbound span. This results in a Positive rating. Environmental Stormwater: Substantial drainage infrastructure improvements would be required as a result of the new northbound corridor on the east side of the existing bridge. In Drainage Zone 1, there are physical space limitations with respect to locating treatment BMPs within the ROW and outside of the water resource protection zones. There is limited opportunity to locate water quality treatment measures in the median between the proposed highway corridors. To the extent that one centralized treatment BMP in the median would not be sufficient to meet water quality objectives, additional stormwater treatment measures would need to be implemented further upstream. In Drainage Zone 3, the New 8-Lane East Bridge Alternative is marginally superior to the other Build Alternatives with respect to an increased opportunity to locate stormwater treatment BMPs within the ROW and outside of existing edge of pavement. This alternative is rated Neutral for this criterion. Drinking Water Quality: Although the additional impervious surface area resulting from the widening of I-95 to the south of the Merrimack River on 3-29

30 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( New 8-Lane West Bridge Alternative) the approach to the new bridges would result in additional volumes of stormwater runoff within the Newburyport water supply protection areas, it is assumed that appropriate stormwater management mitigation would be provided; therefore, this alternative is given a rating of Neutral for this criterion. Wetlands: Salt Marsh, Rocky Intertidal Shore, and Land Subject to Coastal Storm Flowage lie directly under the proposed East bridge span, although no direct impacts would occur to these resources. The amount of Coastal Beach under the bridge could be reduced in this alternative because of the narrowing wetland on the west side. Potential indirect impacts from shading should be minimal because: 1) the proposed bridges would be higher than the existing bridge; 2) there would be two spans with a gap of approximately 40 feet between them; and 3) the abutment would be set further from the river. This configuration would allow considerably more light under the bridge than currently occurs. This alternative is rated Neutral for this criterion. Visual/View Points: This alternative would widen the existing footprint to accommodate two 4-lane bridges and would shift the alignment slightly to the east. This alternative is considered to have a negative impact on the condominium residences adjacent on the east side of the bridge, but a positive impact on the condominiums on the west side of the bridge. For this reason, this alternative was given a Negative rating for this criterion. Historic: This alternative would demolish the existing Whittier Bridge; therefore, this alternative is considered Negative for this criterion. Navigation: The New 8-Lane East Bridge Alternative would limit the inwater construction zone to one side of the bridge and would not be as complex in terms of in-water work as some of the other alternatives; therefore, the construction duration within the waterway would be shorter and the potential for negative impacts to navigation would be less. The New 8-Lane East Bridge Alternative s permanent bridge structure would not result in a reduction of existing vertical or horizontal clearance and there would be no adverse impacts to navigation. This alternative is rated Neutral for this criterion. Conclusion for the New 8-Lane East Bridge Alternative The New 8-Lane East Bridge Alternative has the fewest Negative rankings and the most Positive rankings of any of the Build Alternatives evaluated; therefore, this alternative will be carried forward to the second-level screening analysis New 8-Lane West Bridge Alternative This staging scheme is the mirror image of the New 8-Lane East Bridge Alternative under which a new bridge would be constructed on the west side so that upon completion, all six lanes of traffic on I-95 would be immediately relocated over the new bridge, thus permitting the existing truss spans to be demolished free of traffic and in one phase. The new I-95 northbound carrying four lanes of traffic would be built in the new space provided. Once opened to traffic, the I-95 southbound bridge would be reconfigured for the four lanes and necessary shoulders on each side of the travel lanes. The pier locations for the New 8-Lane West Bridge Alternative are shown on Figure 3-7. Purpose and Need The New 8-Lane West Bridge Alternative would construct a new Merrimack River bridge crossing, which would fully comply with current interstate highway design standards for lane and shoulder widths and would result in two additional travel lanes on I-95; therefore, this alternative would fully comply with the Purpose and Need of the project and is rated Positive for this criterion. Highway Configuration Horizontal Alignment: The bridge tangents for this alternative could be tied back into the existing baseline both north and south of the bridge (see Figure 3-8). The only deviation from the design requirements would be that the large radius curves required on the north- and southbound barrels near the Evan s Place Bridge would not meet the MassDOT requirements for minimum length of curve (Figure 3-8, sheet 3). The impact of this deviation would be minimal because of the large radii. The rating for this category is Neutral. Vertical Alignment: There would be no issues with the vertical profile required for this alternative. The rating for this category is Positive. Impacts to Existing Infrastructure: The alignment required for the southbound barrel south of the bridge to tie the proposed bridge tangent back to the existing highway would affect the Pine Hill/Ferry Road Bridge (Figure 3-8, sheet 1). This alternative would also affect the Route 110 eastbound to I-95 southbound on-ramp and the I-95 northbound to Route 110 eastbound off-ramp (Figure 3-8, sheet 4). The rating for this category is Negative. Bridge Configuration With the exception of Hydraulics, which has a Neutral rating, this alternative has Positive ratings for the remaining five Bridge Configuration subcategories: Design Standards/Complexities, Structural Safety, Context- Sensitive Structure, Maintenance and Inspection, and Life Cycle/Cost. Traffic The New 8-lane West Alternative would construct four lanes in each direction with shoulders on the bridge, similar to the Progressive Alternative. Under this alternative, the three traffic categories of Travel Time, Level of Service (LOS), and Capacity have all been rated Positive (see Section ). Right-of-Way Fee Taking: The proposed southbound bridge location, west of the existing, would force the southbound barrel north of the bridge to affect the ROW ( Figure 3-8, sheet 3). The rating for this category is Negative. Permanent Easement: A permanent easement, to maintain the retaining walls north and south of the bridge crossing, would be required. The rating for this category is Negative. Temporary/Construction Easement: Temporary easements south of the bridge would be required to facilitate constructing retaining walls. The rating for this category is Negative. Cost The New 8-Lane West Alternative would involve a straightforward construction of a new parallel southbound over-width structure adjacent to the existing bridge, transfer of all traffic off the existing structure and subsequent construction of the new northbound span, transfer of northbound traffic, and final reconfiguration of the southbound span. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would allow full crane access from the west side of the existing bridge. This would simplify demolishing the southern approach truss and subsequent dismantling of the existing main span bridge in a reverse manner of its original construction. Once the existing structure is complete, the bridge construction team would be remobilized to complete the construction of the new northbound span. This results in a Positive rating. Construction Utility Relocation: This alternative would reconstruct existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected. For these reasons, this alternative is judged Neutral. 3-30

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36 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Inside Highway Widening Alternative) Constructability/Demolition of Existing Structures: The New 8-Lane West Bridge Alternative would involve a straightforward construction of a new parallel southbound over-width structure adjacent to the existing bridge, transfer of all traffic off the existing structure and subsequent construction of the new northbound span, transfer of northbound traffic, and final reconfiguration of the southbound span. This alternative would provide for the earliest removal of traffic from the existing structure. The construction would be uncomplicated by site constraints, and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would allow full crane access from the west side of the existing bridge. This would simplify demolishing the southern approach truss and subsequent dismantling of the existing main span bridge in a reverse manner of its original construction resulting in a safer operation. Once the existing structure is complete, the bridge construction team would be remobilized to complete the construction of the new northbound span. This results in a Positive rating. Maintenance of Traffic: The bridge staging for this alternative would require that traffic remain in place while the southbound bridge is constructed. Both north- and southbound traffic would then be diverted to the southbound bridge on temporary alignments while the existing bridge is demolished and the new northbound bridge is constructed. Once completed, traffic would be diverted again to the final alignments. During the second stage, the northbound traffic would be forced to cross the existing southbound lanes to reach the temporary alignment on the southbound bridge, necessitating the development of detailed construction sequencing. The temporary alignments required could be designed to meet the design requirements for 70 mph. The rating for this category is Neutral. Schedule The New 8-Lane West Bridge Alternative would involve a straightforward construction of a new parallel southbound over-width structure adjacent to the existing bridge, transfer of all traffic off the existing structure and subsequent construction of the new northbound span, transfer of northbound traffic, and final reconfiguration of the southbound span. The construction would be uncomplicated by site constraints and the subsequent demolition of the existing bridge would be uncomplicated by requirements to modify the existing structure. The staging of this alternative would allow full crane access from the west side of the existing bridge. This would simplify the demolition of the southern approach truss and subsequent dismantling of the existing main span bridge in a reverse manner of its original construction. Once the existing structure is complete, the bridge construction team would remobilize to complete the construction of the new northbound span. This results in a Positive rating. Environmental Stormwater: Substantial drainage infrastructure improvements would be required as a result of the reconfigured southbound highway alignment, which would be located on the west side of the existing bridge. In Drainage Zone 1, there would be an opportunity to locate a substantial treatment BMP within the ROW on the east side of the existing northbound corridor in the vicinity of the existing drainage discharge to the Merrimack River. A benefit to locating a treatment BMP in this area is that it would be outside of any direct overland influence to Bartlett Spring Pond. In Drainage Zone 3, there would be some limitations with respect to locating BMPs because of the existing topography and proximity of wetlands within the existing ROW. The new drainage infrastructure system would be designed to meet all the stormwater management standards for the highway improvements defined as new development and that portion of the improvements that are defined as redevelopment would meet the stormwater standards as required to the maximum extent practical; therefore, the rating for this category is Neutral. Drinking Water Quality: This alternative would result in additional impervious surface area resulting from realignment and widening of the I-95 southbound lanes immediately south of the Merrimack River, resulting in new impervious surface within 400 feet of Bartlett Springs Pond; therefore, this alternative is rated Negative for this criterion. Wetlands: This alternative would result in minor indirect impacts to wetland resource areas located on both banks of the Merrimack River from additional areas of shading resulting from wider new bridge structures, and permanent impacts to the river bottom resulting from the larger footprint of additional bridge piers in the river. The total impacts would be minor; therefore, this alternative is rated Neutral for this criterion. Visual/View Points: The New 8-Lane West Bridge Alternative would widen the existing footprint to accommodate the two 4-lane bridges and shift the alignment slightly to the west. This alternative would have a Negative impact on the condominium residences adjacent on the west side of the bridge, but a Positive impact on the condominiums on the east side of the bridge. For this reason, the alternative is given a Negative rating for this criterion. Historic: This alternative would demolish the existing Whittier Bridge; therefore, this alternative is considered Negative for this criterion. Navigation: The New 8-Lane West Bridge Alternative would limit the inwater construction zone to one side of the bridge and would not be as complex in terms of in-water work as some of the other alternatives; therefore, the construction duration within the waterway would be shorter and the potential for negative impacts to navigation would be less. The New 8-Lane West Bridge Alternative permanent bridge structure would not result in a reduction of existing vertical or horizontal clearance and there would be no adverse impacts to navigation. This alternative is rated Neutral for this criterion. Conclusion for the New 8-Lane West Bridge Alternative The New 8-Lane West Bridge Alternative will not be carried forward to the second-level screening analysis because of the high number of Negative rankings related to Impacts to Existing Infrastructure, ROW, Constructability, and several environmental criteria, in particular potential impacts to the Newburyport public surface water supply Inside Highway Widening Alternative The Inside Highway Widening Alternative would begin at the Route 113 interchange and end at the Route 286 interchange. The alternative would widen the northbound and southbound barrels within the existing median. Purpose and Need This alternative would construct a widened eight-lane I-95 alignment in the project corridor, would add capacity to meet projected future traffic volumes, and provide for an adequate level of service and improved safety. It would also provide a consistent eight-lane cross section throughout the project corridor, matching the I-95 cross section both south and north of the project corridor, and would be consistent with current highway design principles; therefore, this alternative is given a Positive rating for this criterion. Highway Configuration Horizontal Alignment: The alignment modifications required to develop the widening on the inside would meet all of the design requirements (see Figure 3-9). The rating for this category is Positive. Vertical Alignment: The vertical alignment required for this alternative would meet all of the design requirements. The rating for this category is Positive. 3-36

37 Figure 3-9 Inside Highway Widening North of Route 110 Bridge

38 Figure 3-9 Inside Highway Widening North of Route 110 Bridge

39 Figure 3-9 Inside Highway Widening North of Route 110 Bridge

40 Figure 3-9 Inside Highway Widening North of Route 110 Bridge

41 Figure 3-9 Inside Highway Widening North of Route 110 Bridge

42 Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Inside Highway Widening Alternative) Impacts to Existing Infrastructure: This alternative would avoid impacts to all existing bridges, with the exception of the I-95 bridges over Route 110 and the railroad ROW. The northbound off-ramp at the Route 286 interchange would be affected to allow the inside widening to transfer to the outside for the auxiliary lane drop. The rating for this category is Positive. Traffic Travel Time: Travel time was analyzed throughout the corridor to determine the amount of time it would take a vehicle to traverse multiple segments. The results of widening versus not widening in terms of the travel-time improvements with Build and No Build Alternative conditions for 2030 are listed in Table 3-1 and Table 3-2 for northbound and southbound, respectively. Capacity: By adding lanes on the interstate, the Inside Highway Widening Alternative would increase both the capacity per lane per hour and overall capacity per link per hour. Additional lanes make it easier for vehicles to pass slow-moving vehicles and to provide more gaps to improve merging, weaving, and diverging operations that occur on the interstate. The capacity analysis for bridge staging alternatives described previously details how free-flow speed and capacity were derived using HCM methodology. Table 3-5 shows the additional capacity provided by additional lanes using the HCM analysis; therefore, in terms of capacity, the Inside Highway Widening Alternative is rated Positive. TABLE 3-1: Segment TRAVEL TIME ANALYSIS: I-95 NORTHBOUND NO BUILD AND BUILD SATURDAY AM PEAK CONDITIONS (INSIDE WIDENING) Distance (ft) I-495 to Route 286 2,825 North of Route 110 to I-495 to Whittier Bridge to north of Route 110 6,215 4,440 Whittier Bridge 1,346 Hwy 113 to Whittier Bridge TOTAL 3,035 17,861 ft (3.4 miles) No Build vs. Build Speed mph (ft/sec) Travel Time (sec) No Build (29.05) 97.3 Build (39.14) 72.2 No Build (25.63) Build (42.83) No Build (43.15) Build (43.87) No Build (39.5) 34.1 Build (44.01) 30.6 No Build (39.46) Build (44.0) 68.9 No Build (9.1 min) Build (7.0 min) TABLE 3-2: TRAVEL TIME ANALYSIS: I-95 SOUTHBOUND NO BUILD AND BUILD SUNDAY PM PEAK CONDITIONS (INSIDE WIDENING) Segment Distance (ft) No Build vs. Build Speed mph (ft/sec) Travel Time (sec) Route 286 to I-495 3,305 No Build (33.12) 99.8 Build (37.33) I-495 to north of Route 110 5,540 No Build (42.53) Build (44.1) North of Route 110 to No Build (45.52) ,900 Whittier Bridge Build (44.30) 88.0 Whittier Bridge 1,346 No Build (39.41) 34.2 Build (43.91) 30.7 Whittier Bridge to Hwy 113 2,880 No Build (43.63) 65.8 Build (44.0) TOTAL No Build 16,971 ft (7.0 min) (3.2 miles) Build (6.6 min) TABLE 3-3: LOS ANALYSIS: I-95 NORTHBOUND (INSIDE WIDENING) 3 Lanes 4 Lanes 5 Lanes Density Density Density Location (pc/mi/ln) LOS (pc/mi/ln) LOS (pc/mi/ln) LOS Between Route 286 & I-495 >45 F 29.9 D North of Route 110 to I-495 >45 F 20.2 C Whittier Bridge 31.2 D 21.7 C Notes: Existing I-95 (No Build Alternative) provides three lanes between the southern limits of the project to I-495, and four lanes from I-495 to Route 286. Build Alternative conditions would provide four lanes between the southern limits of the project to I-495, and five lanes from I-495 to Route 286. pc/mi/ln = passenger cars per mile per lane TABLE 3-4: LOS ANALYSIS: I-95 SOUTHBOUND (INSIDE WIDENING) 3 Lanes 4 Lanes 5 Lanes Density Density Density Location (pc/mi/ln) LOS (pc/mi/ln) LOS (pc/mi/ln) LOS Between Route 286 & I-495 >45 F 29.4 D North of Route 110 to I C 18.9 C Whittier Bridge 40.8 E 24.6 C Notes: Existing I-95 (No Build Alternative) provides three lanes between the southern limits of the project to I-495, and four lanes from I-495 to Route 286. Build Conditions would provide four lanes between the southern limits of the project to I-495, and five lanes from I-495 to Route 286. pc/mi/ln = passenger cars per mile per lane TABLE 3-5: LANE CAPACITY ANALYSIS (INSIDE WIDENING) 3-Lanes 4 Lanes 5 Lanes Base FFS (mph) flw flc fn fid FFS (mph) Capacity/Hr/Lane 2,370 2,385 2,400 TOTAL CAPACITY/HR 7,110 9,540 12,000 Right-of-Way Fee Taking: No fee takings would be required for this alternative, so the rating is Positive. Permanent Easement: Permanent easements would be required for this alternative to accommodate stormwater basins; therefore, the rating is Negative. Temporary/Construction Easement: No temporary/construction easements would be required for this alternative, so the rating is Positive. Cost The Inside Highway Widening Alternative would involve a straightforward construction of new lanes of interstate highway in the existing 60-footwide median. Costs are included for the widening of the I-95 Exit 58 and I-95 railroad bridges. This alternative would avoid the reconstruction of the three northern terminus bridges. This results in a Positive rating for the alternative. Construction Utility Relocation: This alternative would reconstruct existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected. For these reasons, this alternative is judged Neutral. Constructability/Demolition of Existing Structures: The Inside Highway Widening Alternative would involve a straightforward construction of new lanes of interstate highway in the existing 60-foot-wide median. There are no discernable constructability concerns except for the work zone access and safety concerns to the high-speed lanes. This alternative would not reconstruct the three northern terminus bridges. This results in a Positive rating for the alternative. 3-42

43 Maintenance of Traffic: This alternative would be constructed in one phase with little impact to traffic. The rating for this category is Positive. Schedule The Inside Highway Widening Alternative would involve a straightforward construction of new lanes of interstate highway in the existing 60-footwide median. There are no discernable schedule concerns except for the work zone access to the high-speed lanes. This alternative would not reconstruct the three northern terminus bridges. This results in a Positive rating for the alternative. Environmental Stormwater: Substantial drainage infrastructure improvements would be required as a result of the highway widening. The existing inside lanes discharge stormwater runoff via sheet flow off the edge of the pavement and into the median between the northbound and southbound lanes. The proposed Inside Highway Widening Alternative would present an opportunity to utilize a sheet flow drainage system; however, it is unlikely that the targeted stormwater goals would be achieved exclusively in the proposed median. This alternative would allow the positioning of BMPs, which would provide the required levels of water quality treatment and peak-flow attenuation outboard of the existing highway. On a project wide basis, the BMPs would provide treatment for an area equivalent to the overall new development area and provide additional treatment for a portion of the redevelopment area. On a project-wide basis, this alternative would meet the stormwater standards of the Massachusetts Stormwater Handbook; therefore, this alternative is rated Positive for this criterion. Drinking Water Quality: This alternative includes constructing an improved stormwater management system along the project corridor and would result in treatment and improved discharge water quality. Although this alternative would result in increased impervious surface and increased stormwater runoff volume within the Newburyport and Salisbury water supply protection areas, this alternative is considered Neutral for this criterion. Wetlands: This alternative would result in minimal additional direct wetland impacts from highway widening activities. There are no jurisdictional wetland resources in the highway median along the project corridor. Minor impacts could result from constructing stormwater management improvements, but these potential impacts cannot be quantified at this time. This alternative is given a Positive rating for this criterion. Historic: The ranking for this alternative does not consider the historic impacts of the bridge crossing, only the widened I-95 corridor. As all widening is proposed to be constructed entirely within the existing highway ROW, there are no direct impacts to existing historic resources anticipated for this alternative; therefore, this alternative is rated Positive for this criterion. Conclusion for the Inside Widening Highway Alternative The Inside Widening Highway Alternative screening evaluation results in the most Positive ratings and only one Negative rating for applicable criteria; therefore, this alternative will be carried forward to the second-level screening analysis Outside Highway Widening Alternative The Outside Highway Widening Alternative would begin at the Route 113 interchange and end at the Route 286 interchange. The alternative would widen the northbound and southbound barrels to the outside of the existing highway. Purpose and Need This alternative would construct a widened eight-lane I-95 alignment in the project corridor, would add capacity to meet projected future traffic volumes, and provide for an adequate level of service and improved safety. It would also provide for a consistent eight-lane cross section throughout the project corridor, matching the I-95 cross section both south and north of the project corridor, consistent with current highway design principles; therefore, this alternative is rated Positive for this criterion. Highway Configuration Horizontal Alignment: The existing I-95 alignment would be maintained for this alternative ( Figure 3-10). The rating for this category is Positive. Vertical Alignment: The vertical alignment required for this alternative would meet all of the design requirements. The rating for this category is Positive. Impacts to Existing Infrastructure: This alternative would affect all of the ramps at the Route 110 and I-495 interchanges, and the northbound offramp and southbound on-ramps at the Route 286 interchange (Figure 3-10, sheet 5). In addition to the I-95 bridges over Route 110 and the railroad ROW, this alternative would affect the railroad ROW bridge on Whittier Bridge/I-95 Improvement Project EA/DEIR Chapter 3.0: Project Alternatives ( Outside Highway Widening Alternative) the northbound on-ramp from Route 110, the I-495 overpass, and the Route 286 overpass. The rating for this category is Negative. Traffic Similar to the Inside Highway Widening Alternative, this alternative would construct a widened eight-lane I-95 alignment in the project corridor. As shown in Section (Tables 3-1 through 3-5), Travel Time, Level of Service, and Capacity are all rated as Positive. Right-of-Way Fee Taking: No fee takings would be required for this alternative so the rating is Positive. Permanent Easement: Permanent easements would be required for this alternative to accommodate stormwater basins; therefore, the rating is Negative. Temporary/Construction Easement: The anticipated toe of slope for this alternative would be very close to the ROW in some locations. Temporary construction easements could be required. The rating for this category is Negative. Cost The Outside Highway Widening Alternative would involve a straightforward construction of new lanes of interstate highway in the existing shoulders. Costs are included for the widening of the I-95 Exit 58, and I-95 railroad bridges. This alternative would reconstruct northbound and southbound I-95 ramps at Exit 58 and reconstruct the three northern terminus bridges and I-95 southbound Exit 58 ramps. This results in a Negative rating for the alternative. Construction Utility Relocation: This alternative would reconstruct existing utility crossings within the I-95 project corridor to maintain the existing utility infrastructure. No temporary or permanent interruptions to existing utilities are expected. For these reasons, this alternative is judged to be Neutral. Constructability/Demolition of Existing Structures: The Outside Highway Widening Alternative would involve a straightforward construction of new lanes of interstate highway in the existing shoulders. There are no discernable constructability concerns except for the reconstruction of northbound and southbound I-95 ramps at Exit 58, the work zone access, and safety concerns to the northbound high-speed lane. This alternative would reconstruct the three northern terminus bridges. This results in a Negative rating for the alternative. 3-43

44 Figure 3-10 Outside Highway Widening North of Route 110 Bridge

45 Figure 3-10 Outside Highway Widening North of Route 110 Bridge

46 Figure 3-10 Outside Highway Widening North of Route 110 Bridge

47 Figure 3-10 Outside Highway Widening North of Route 110 Bridge

48 Figure 3-10 Outside Highway Widening North of Route 110 Bridge