ST. CROIX RIVER CROSSING PROJECT SUPPLEMENTAL ......CHAPTER 3 PROPOSED PROJECT – IDENTIFICATION OF THE PREFERRED ALTERNATIVE 3.0 INTRODUCTION This chapter describes the Preferred

JUNE 2006 St. Croix River Crossing Project 3 - 1 Supplemental Final EIS

ST. CROIX RIVER CROSSING PROJECT SUPPLEMENTAL FINAL EIS CHAPTER 3

PROPOSED PROJECT – IDENTIFICATION OF THE PREFERRED ALTERNATIVE

3.0 INTRODUCTION

This chapter describes the Preferred Alternative identified for the St. Croix River Crossing project. It also discusses the various alternatives from the SDEIS that have been dismissed from further consideration.

A replacement bridge crossing near Stillwater, Minnesota, and the Town of St. Joseph, Wisconsin, has been discussed for many years. Formal assessment of the alternatives to address growing transportation problems in the area began with the preparation of the St. Croix River Crossing Draft Study Outline and Scoping Document (1985). Numerous studies, as discussed in Chapter 1 of this SFEIS, have been completed since that time.

Alternatives assessed with the 1985 Scoping Document eventually led to the analysis of three river crossing corridor alternatives and two tunnel alternatives with the 1990 Draft Environmental Impact Statement (DEIS). A Preferred Alternative was identified in the 1995 Final Environmental Impact Statement (FEIS). Final design, right-of-way acquisition, and site preparation began on the 1995 Preferred Alternative but were halted following the finding of the NPS Section 7(a) Evaluation in 1996.

New alternatives, including consideration of the future of the Lift Bridge, were identified as part of the Braun Facilitation Process in 1998. This led to identification of the Braun C Alternative, later referred to as the “Consensus Alternative.” Documentation of the Braun C Alternative in a Supplemental Draft EIS was halted in January 2001 due to the inability to reach a consensus on the future of the Lift Bridge.

In 2002, FHWA, Mn/DOT, and WisDOT re-initiated the St. Croix River Crossing Project EIS process with alternatives recommended during the Braun Facilitation Process as well as the 1995 FEIS Preferred Alternative and Stakeholder recommended alternatives. This led to the identification of six alternatives in the 2003 Amended Scoping Document; the 2004 Amended Final Scoping Decision Document identified four alternatives in addition to the No-Build Alternative for study in the 2004 SDEIS.

The 2004 St. Croix River Crossing Project Supplemental Draft Environmental Impact Statement (SDEIS) is incorporated by reference and is considered to be a part of this Supplemental Final EIS (SFEIS).

3.1 RIVER CROSSING ALTERNATIVES DISMISSED PRIOR TO THE SUPPLEMENTAL DRAFT EIS

St. Croix River Crossing alternatives dating back to 1987 are illustrated and described in Chapter 3 of the SDEIS. As a result of the analysis completed during the amended scoping phase in 2003-2004, two of the six initial alternatives presented in the 2003 Amended Scoping


Document were screened from consideration. A brief description of these alternatives is included below. 3.1.1 Alternative A – TSM/TDM Alternative Alternative A included the permanent rehabilitation and continued vehicular use of the Lift Bridge. Needed mobility would be provided through a combination of TSM/TDM measures as described in the 2003 Amended Scoping Document. Alternative A was determined not to meet the purpose and need of the project as described in the 2004 Amended Final Scoping Decision Document and was screened from further consideration in the SDEIS. Section 2.2.3 of the SDEIS discusses the ability of TSM/TDM measures to address the transportation issues of the project. Specifically, Section 2.2.3.2 of the SDEIS summarizes the analysis of Alternative A during the scoping period. However, travel demand forecasts did indicate a potential market for transit both within St. Croix County and between western Wisconsin and Minnesota in the Twin Cities area. A workshop with local and regional government representatives, state DOT representatives, and other interested stakeholders was held in December 2004 to identify the scope and action plan for a separate transit feasibility study. The workshop and feasibility study are discussed in Section 15.4.1.2 of this SFEIS. 3.1.2 Alternative B Alternative B was the original 1995 Final EIS Preferred Alternative alignment. This alternative alignment was reviewed by the National Park Service (NPS) under Section 7(a) of the Wild and Scenic Rivers Act for the 1995 Final EIS. The NPS determined that this alternative would have a direct and adverse effect on the St. Croix Riverway. Discussion with the NPS during the 2003-2004 scoping period indicated that a reversal of that determination with a different bridge type or profile than what was proposed in 1995 was not likely. Thus, Alternative B was screened from further study in the SDEIS. 3.2 ALTERNATIVES STUDIED IN THE SUPPLEMENTAL DRAFT EIS AND

DISMISSED 3.2.1 No-Build Alternative The No-Build Alternative assessed in the SDEIS assumed only continued operation of the Lift Bridge and approach roadways. This included the $5 Million Lift Bridge Repair Project that began in summer 2005 (refer to Chapter 1 of this SFEIS). The existing approach roadways and river crossing contain a number of transportation deficiencies that would be perpetuated under the No-Build Alternative. The deficiencies of the existing system are discussed in detail in Chapter 2 of the SDEIS and are summarized below:


• Operational issues

− Poor traffic operations

− Delays due to Lift Bridge operations

− High pedestrian volumes in downtown Stillwater affecting traffic operations

− Diversion of traffic from arterial roadways to local collector streets

• Geometric issues

• Capacity issues

• Reliability issues associated with the Lift Bridge

• Safety issues with the existing roadway system, including delayed emergency vehicle response

The No-Build Alternative was not identified as the Preferred Alternative because existing deficiencies (operational, geometric, and capacity) would persist and will become worse as anticipated development in the project area will increase traffic on the roadway system in the future. However, the No-Build Alternative was used as a basis of comparison in the SDEIS and is used as a basis of comparison for the Preferred Alternative in this SFEIS. 3.2.2 SDEIS Build Alternatives The SDEIS addressed four Build Alternatives (Figure 3-1). Alternative B-1 consisted of two sub-alternatives. Under Alternative B-1a, the Lift Bridge would be converted to a pedestrian/bicycle facility. Under Alternative B-1b, use of the Lift Bridge would be limited to local vehicular traffic. Continued vehicular use of the Lift Bridge for local traffic or conversion of the Lift Bridge to a pedestrian/bicycle facility was also applicable to Alternative C. However, this scenario was only studied under Alternative B-1. Alternative C was studied in the SDEIS assuming the Lift Bridge was converted to a pedestrian/bicycle facility. The traffic operations and related results (e.g., noise impacts; air quality impacts) from Alternative B-1b were assumed to be similar under Alternative C with the Lift Bridge open to limited, local vehicular use. The design features of TH 36 segment (TH 5 to Osgood Avenue) was the same for all Build Alternatives studied in the SDEIS. Under the SDEIS Build Alternatives, TH 36 would be converted to a grade-separated facility with reconstructed frontage roads and buttonhook-type interchanges (see Figure 3-2 of the SDEIS). The TH 36 (TH 5 to Osgood Avenue) design features for the Preferred Alternative are described in Section 3.3.2 of this SFEIS. FHWA, Mn/DOT, and WisDOT identified Alternative B-1a as the Preferred Alternative (see Section 3.3 of this SFEIS) in fall 2004. The three Build Alternatives described in the following sections were not identified as the Preferred Alternative. 3.2.2.1 Alternative C Alternative C would reconstruct TH 36 in Minnesota as a grade-separated facility from TH 5 to Osgood Avenue with reconstructed frontage roads. An offset-diamond interchange would be constructed east of Osgood Avenue to provide for all movements between TH 36 and


TH 95. The Alternative C four-lane river crossing is located approximately 4,450 feet south of the Lift Bridge along the Minnesota shoreline of the St. Croix River and approximately 3,600 feet south of the Lift Bridge along the Wisconsin shoreline. The Lift Bridge would be converted to a pedestrian/bicycle facility or continue to operate for local traffic. Two location options were considered for the Wisconsin approach roadways with Alternative C. Alternative C – Option 1 would continue northeast from the Alternative C river crossing and turn north after passing under STH 35, connecting with existing STH 35/64 northeast of Houlton. Alternative C – Option 2 would continue northeast from the Alternative C river crossing, connecting with existing STH 35/64 at 20th Street. Under both options, the new STH 64 roadway would be constructed as a limited-access, four-lane rural section roadway. The estimated cost for this alternative is approximately $230 million to $285 million, depending upon bridge type (see Section 3.8 of the SDEIS). Alternative C was similar to Alternative B-1 in many transportation impacts, including river crossing reliability; congestion; decreases in Vehicle Hours Traveled (VHT; indication of the overall system efficiency); Regional Daily Vehicle Miles Traveled (VMT; another indication of the overall system efficiency); and the amount of local travel diversion. Alternative C differed slightly from Alternative B-1 in several measures. Alternative C may experience one merge/diverge movement (TH 36 traffic taking the TH 95 off-ramp) that is approaching LOS E. Under Alternative C, the number of accidents forecasted for the period 2011 to 2030 will be reduced by over 600 crashes. Although this is a substantial improvement, Alternative B-1 showed a forecasted reduction of over 1,300 accidents, double the level of improvement under Alternative C. Environmental, cultural and social considerations, as noted below, were more critical than the transportation impacts in rejecting Alternative C as the preferred alternative. • Construction of the Alternative C river crossing would require acquisition of property from

the Stillwater Municipal Barge Facility property (a Section 4(f) resource), a City of Stillwater-planned park.

• While Alternative C – Option 2 in Wisconsin would result in fewer farmland acres acquired compared to Alternative B-1, Alternative C – Option 2 would result in greater fragmentation of both farmland and woodland between 13th Street and 20th Street. Alternative C – Option 2 would also result in the acquisition of 10 residential lots in Settler’s Glen development.

• More residential receptors would experience noise impacts (as defined by Wisconsin Chapter Trans. 405) under both Alternative C – Option 1 and Option 2 than with Alternative B-1.

• Nine high-risk potentially-contaminated sites would be potentially affected by Alternative C compared to six sites for Alternative B-1.

• Greater amount of acreage disturbed on the Wisconsin bluff than with Alternative B-1.

• Greater longitudinal impacts to the 100-year floodplain in Minnesota from roadway construction than with Alternative B-1.

• Greater area of wetland encroachment (approximately 0.6-acre greater with Option 1; approximately 1.25 acres greater with Option 2) compared to Alternative B-1.


3.2.2.2 Alternative D Alternative D would reconstruct TH 36 in Minnesota as a grade-separated facility from TH 5 to Osgood Avenue with reconstructed frontage roads. A modified offset diamond interchange would be constructed east of Osgood Avenue to provide for all movements between TH 36 and TH 95. A directional three-level interchange would be constructed near downtown Stillwater to provide for all movements from TH 36/95 and downtown Stillwater. The Alternative D four-lane river crossing is located approximately 1,900 feet south of the Lift Bridge along the Minnesota shoreline and approximately 160 feet south of the Lift Bridge along the Wisconsin shoreline. Under Alternative D, the Lift Bridge would be converted to a pedestrian/bicycle facility. Alternative D would reconstruct STH 64 in Wisconsin as a four-lane facility east of the Lift Bridge through Houlton to the existing STH 35/64 alignment near Andersen Scout Camp Road. A new interchange would be constructed east of Houlton with a new local road connection to existing STH 35. A new two-lane STH 35 roadway would be constructed from south of Houlton, intersect with CTH E, and continue north to the interchange with STH 64. The estimated cost for this alternative is approximately $245 million to $310 million, depending upon bridge type (see Section 3.8 of the SDEIS). Like Alternative C, Alternative D was similar to Alternative B-1 in many transportation impacts, including river crossing reliability, congestion, decreases in Vehicle Hours Traveled (VHT) and Vehicle Miles Traveled (VMT). Alternative D may experience unacceptable LOS E or F at the TH 36/95 interchange ramps; it also presents more local intersections operating at unacceptable LOS (LOS E or F) than with Alternative B-1. Under Alternative D, the number of accidents forecasted for the period 2011 to 2030 will be reduced by over 600 crashes. Although this is a substantial improvement, Alternative B-1 showed a forecasted reduction of over 1,300 accidents, double the level of improvement under Alternative D. Environmental, cultural and social considerations, as noted below, were more critical than the transportation impacts in rejecting Alternative D as the preferred alternative. • More residential and commercial properties would be acquired under Alternative D than with

Alternative B-1.

• Substantial portions of the Stillwater Municipal Barge Facility property (a Section 4(f) resource) would be required to accommodate TH 95 and the Alternative D river crossing, resulting in a limited amount of land available for future park development.

• Close proximity of Alternative D river crossing to downtown Stillwater would result in visual impacts to Lowell Park (a Section4 (f) resource).

• Land would be acquired from Kolliner Park (a Section 4(f) resource) to accommodate the Alternative D river crossing and new STH 64 whereas Alternative B-1 will not acquire land from Kolliner Park.

• Nine high-risk potentially-contaminated sites requiring remediation would be potentially affected by Alternative D compared to six sites for Alternative B-1.


• While the Alternative D approach roadway in Wisconsin would be located within an existing bluff cut, the quantitative impacts to the bluff would be substantially larger and would also require substantial retaining wall systems to minimize bluff cut activities.

• Greater longitudinal and transverse impacts to the 100-year floodplain in Minnesota from roadway and pond construction than with Alternative B-1.

• Greater area of wetland encroachment (approximately 1.3 acres greater) compared to Alternative B-1.

• Seven NRHP-listed, determined eligible, or potentially-eligible historic properties would be adversely affected by Alternative D, compared to six properties for Alternative B-1.

In addition to the items listed above, the likelihood of receiving a positive Section 7(a) Evaluation from the National Park Service (NPS) with Alternative D was unknown and contributed to the elimination of the alternative from further consideration. In a preliminary review of the Build Alternatives for the SDEIS, the NPS had indicated that Alternative D may not be able to receive a favorable Section 7(a) Evaluation, even with a strong mitigation package. 3.2.2.3 Alternative E Alternative E would reconstruct TH 36 in Minnesota as a grade-separated facility from TH 5 to Osgood Avenue with reconstructed frontage roads. A modified single-point interchange would be constructed east of Osgood Avenue to provide full access between TH 36 and TH 95. The Alternative E two-lane new river crossing would accommodate one-way, eastbound traffic; it is located approximately 2,000 feet south of the Lift Bridge along the Minnesota shoreline and approximately 200 feet south of the Lift Bridge along the Wisconsin shoreline. A ramp and intersection on TH 95 would provide for access from downtown Stillwater to the eastbound river crossing of Alternative E. Under Alternative E, the Lift Bridge would be rehabilitated and accommodate two lanes of one-way westbound traffic. The Lift Bridge would remain on the trunk highway system. STH 35/64 reconstruction in Wisconsin under Alternative E would be the same as described for Alternative D. The estimated cost for this alternative is approximately $230 million to $275 million, depending upon bridge type (see Section 3.8 of the SDEIS). Many of the same reasons listed above for not identifying Alternative D as the Preferred Alternative also apply to Alternative E. Alternative E, however, would utilize the Lift Bridge for vehicular traffic, and would be affected by congestion related to bridge closings and regular bridge deck lifts for navigation. Alternative E was not identified as the Preferred Alternative because: • River crossing reliability would be compromised with the Lift Bridge operating as a trunk

highway facility for two lanes of one-way westbound traffic. The Lift Bridge and trunk highway traffic would still be subject to closures due to deck lifts, flooding, and maintenance.


• The reduction in projected traffic volumes on TH 36/STH 64 under Alternative E compared to Alternative B-1 suggests somewhat constrained conditions.

• When the Lift Bridge is closed, congestion impacts would be substantial because Alternative E relies on the Lift Bridge for westbound traffic.

• Regional Vehicle Hours Traveled (VHT) would decrease with Alternative E compared to the No-Build Alternative; however, this decrease is less than with Alternative B-1.

• Regional Daily Vehicle Miles Traveled (VMT) would increase with Alternative E compared to the No-Build Alternative. Regional Daily VMT would decrease with Alternative B-1.

• More local intersections operating at unacceptable LOS (LOS E or F) than with Alternative B-1.

• The congestion in downtown Stillwater, particularly during Lift Bridge closings, would substantially affect incident management/emergency response times.

• Less accident reduction would be possible than with Alternative B-1.

• Westbound trunk highway traffic would continue to travel through downtown Stillwater, resulting in continued vehicle/pedestrian conflicts, creating unsafe conditions for both pedestrians and motorists.

• The transportation benefit/cost ratio is approximately half that of Alternative B-1.

• Alternative E is less compatible with regional transportation plans, because the Lift Bridge would be operated for trunk highway traffic, than with Alternative B-1.

Environmental, cultural and social considerations, as noted below, were also critical in rejecting Alternative E as the preferred alternative. • While the Alternative E approach roadway in Wisconsin would be located within an existing

bluff cut, the quantitative impacts to the bluff would be substantially larger and would also require substantial retaining wall systems to minimize bluff cut activities.

• More residential and commercial properties would be acquired under Alternative E than with Alternative B-1.

• Substantial portions of the Stillwater Municipal Barge Facility property (a Section 4(f) resource) would be required to accommodate TH 95 and the Alternative E river crossing, resulting in a limited amount of land available for future park development.

• Close proximity of Alternative E river crossing to downtown Stillwater would result in visual impacts to Lowell Park (a Section 4(f) resource).

• Land would be acquired from Kolliner Park (a Section 4(f) resource) to accommodate the Alternative E river crossing and new STH 64 whereas Alternative B-1 will not acquire land from Kolliner Park.

• Greater longitudinal and transverse impacts to the 100-year floodplain in Minnesota from roadway and pond construction than with Alternative B-1.

• Greater area of wetland encroachment (approximately 1.3 acres greater) compared to the Alternative B-1.


• Seven NRHP-listed, determined eligible, or potentially-eligible historic properties would be adversely affected by Alternative E, compared to six properties for Alternative B-1.

The likelihood of receiving a positive Section 7(a) Evaluation from the NPS with Alternative E, similar to Alternative D, was unknown and contributed to the elimination of the alternative from further consideration. In a preliminary review of the Build Alternatives for the SDEIS, the NPS had indicated that Alternative E may not be able to receive a favorable Section 7(a) Evaluation, even with a strong mitigation package. 3.3 IDENTIFICATION OF THE PREFERRED ALTERNATIVE PACKAGE The St. Croix River Crossing Project was developed using a collaborative interdisciplinary approach that involved all stakeholders. This approach balanced three elements: the project’s “fit” within the physical setting; preservation of scenic, aesthetic, historic, and natural environmental resources; and safety and mobility improvements. The St. Croix River Crossing Project Preferred Alternative package consists of four elements: Preferred Alternative river crossing location and approach roadway designs. FHWA, Mn/DOT, and WisDOT identified Alternative B-1a as the Preferred Alternative river crossing location (hereafter referred to as the Preferred Alternative) and presented it to the Stakeholder Group in October 2004. The reasons used in identifying the Preferred Alternative are discussed in Section 3.3.8 of this SFEIS. The layout of the Preferred Alternative is illustrated in Figures 3-2, 3-3, and 3-4. Figures 3-2, 3-3, and 3-4 also include references to typical section figures in Chapter 3 of this SFEIS as well as other elements of the Preferred Alternative package. Preferred Alternative bridge type. An extradosed bridge type was identified as the Preferred Alternative bridge type. The Preferred Alternative bridge and the rationale for identifying the extradosed bridge as the Preferred Alternative bridge type is described in greater detail in Section 3.3.5.2 of this SFEIS. Chapter 7 of this SFEIS describes the visual impacts associated with the Preferred Alternative river crossing and bridge type. Future use of the Lift Bridge. Under the Preferred Alternative, the Lift Bridge will no longer carry vehicular traffic and will be converted to a pedestrian/bicycle facility. The Lift Bridge will be a component of the loop trail mitigation item, which will provide a trail connection between Minnesota and Wisconsin utilizing both the Lift Bridge and new river crossing. Refer to Section 3.3.6 of this SFEIS for additional discussion of the future use of the Lift Bridge. Preferred Alternative mitigation package. The Preferred Alternative mitigation package includes non-design items to address impacts to the St. Croix Riverway and historic resources. These non-design mitigation items are described in detail in Section 15.4 of this SFEIS. Additional discussion of historic resources mitigation is located in the Section 106 Amended Memorandum of Agreement in Appendix G of this SFEIS.


The total length of the Preferred Alternative construction/reconstruction is approximately 6.0 miles and includes: • Approximately 1.8 miles of approach roadway in Minnesota;

• 4,950-foot bridge between bridge abutment in Minnesota and bridge abutment in Wisconsin (2,840-foot bridge crossing over the St. Croix River); and

• Approximately 3.3 miles of approach roadway in Wisconsin. The design features of the Preferred Alternative are described below in the following sections of this chapter. 3.3.1 Location The western project terminus is located at the TH 5/TH 36 interchange in Minnesota; the eastern project terminus is located at the 150th Avenue overpass in Wisconsin. No improvements will be implemented on TH 36 from the western project terminus to a point approximately 1,050 feet east of the Washington/Norell intersection due to the recent improvements to the TH 5/TH 36 interchange and to the frontage roads west of the Washington/Norell intersection. The segment of TH 36 proposed for reconstruction in Minnesota begins approximately 1,050 feet (0.3-mile) east of the Washington/Norell intersection with TH 36 and extends to the St. Croix River. The new river crossing proposed for construction is located approximately 7,550 feet south of the Lift Bridge and downtown Stillwater along the Minnesota shoreline of the St. Croix River and approximately 6,450 feet south of the Lift Bridge along the Wisconsin shoreline. The segment of STH 64 proposed for construction in Wisconsin is located between the St. Croix River and the 150th Avenue overpass in the Town of St. Joseph. 3.3.2 Trunk Highway (TH) 36 – TH 5 to the TH 36/95 Interchange The following sections describe the reconstruction of TH 36 from TH 5 to Osgood Avenue as part of the Preferred Alternative discussed throughout this SFEIS. The following sections also describe improvements to TH 36 east of Osgood Avenue to the TH 36/95 interchange. 3.3.2.1 Information on TH 36 (TH 5 to Osgood Avenue) Since the SDEIS As described in the SDEIS, the proposal considered for reconstruction of TH 36 in Minnesota from TH 5 east to Osgood Avenue included a grade-separated facility with buttonhook-type interchanges, reconstruction of the north and south frontage roads, and construction of pedestrian/bicycle facilities along the frontage roads. This alternative, referred to as the “Buttonhook Concept” or “Concept F,” was developed following the recommendations of the TH 36 Partnership Study and input from a Technical Advisory Group (TAG) during this project’s scoping period. Refer to Section 3.2 of the SDEIS for additional discussion on the alternative development for TH 36. Cut and Cover Concept During the SDEIS comment period in the fall of 2004, residents and business owners in the Stillwater and Oak Park Heights area expressed concern about the right-of-way impacts and the impact on local businesses with Concept F. Local participants wanted to explore other potential


alternatives, and developed one known as the “Cut and Cover” Concept. This concept entailed the following elements: • TH 36 would be depressed with retaining walls between TH 36 and the adjacent frontage

roads;

• Slip ramps would provide access between the TH 36 mainline and frontage roads;

• Decks would be constructed over the depressed TH 36 at cross-street locations (Washington/Norell; Oakgreen/Greeley; Osgood). Frontage roads and cross-streets would intersect at a signalized intersection at either side of the deck overpass.

• Frontage roads would be reconstructed along their existing alignment and converted to one-way roadways;

• Park-like amenities would be provided at deck locations and incorporated throughout the corridor; and

• Pedestrian/bicycle facilities would also be provided throughout the corridor. The local volunteers distributed comment cards to Oak Park Heights and Stillwater residents during the SDEIS public comment period, and received strong support for the Cut and Cover concept (refer to Chapter 17 of this SFEIS for SDEIS comment letters from Oak Park Heights, Stillwater, and Washington County). After discussions with Oak Park Heights, Stillwater, and Washington County, Mn/DOT completed a review of the Cut and Cover Concept in November 2004. This review noted several concerns related to the Cut and Cover Concept including: vertical (e.g., elevation changes between TH 36 and the frontage roads) and horizontal issues (e.g., distances between ramp merge and diverge points; required ramp lengths); cross section issues with the mainline, slip ramps and frontage roads (e.g., need to consider staging and construction needs; adequate roadway width); drainage issues (e.g., ponding requirements that avoid additional wetland and floodplain impacts), intersection geometrics and traffic control issues; potential impacts to adjacent properties including access restrictions; construction staging issues (i.e., anticipated minimum of 6 years for construction); as well as the anticipated substantial costs associated with the bridges and retaining walls of the Cut and Cover Concept. The review concluded that the ability to resolve these issues could not be determined without an extensive engineering effort, which could not be completed within the timeframe then established for the EIS process. In January 2005, Mn/DOT provided a report to both Stillwater and Oak Park Heights City Councils regarding the options for TH 36 including the Cut and Cover Concept, the costs associated with these options, and time requirements associated with the alternatives or any additional studies. Mn/DOT did not consider the Cut and Cover Concept a feasible alternative to Concept F, because of the issues, potential impacts and the need for additional funds for further investigation associated with the Cut and Cover Concept. Mn/DOT also noted that without agreement from Oak Park Heights and Stillwater on the future, long-term design of TH 36, Mn/DOT would go forward into the SFEIS with the TH 36 design approved by the municipalities with the 1995 St. Croix River Crossing Final EIS. On February 15, 2005, the Stillwater City Council passed Resolution 2005-42, a resolution supporting the Alternative B-1 river crossing alignment with the TH 36 at-grade intersections,


the alternative approved with the 1995 St. Croix River Crossing Final EIS. This resolution also noted that enhancements to the TH 36 design be considered at a later date. On March 8, 2005, the Oak Park Heights City Council approved Resolution 05-03-13 establishing the City’s position on a new river crossing and TH 36 improvements. The following is a summary of Oak Park Heights’ Resolution 05-03-13: • Any TH 36 improvements must minimize the social, environmental; economic, infra-

structure, community burdens, and local traffic impacts to the City of Oak Park Heights;

• Oak Park Heights agreed to the year 2000 municipal consent process to find an acceptable design solution to TH 36 that fulfills the best interest of its citizens;

• Oak Park Heights requested that Mn/DOT support federal legislation that includes funding for a TH 36 design study; and

• Oak Park Heights requested that Mn/DOT, the State of Minnesota, and Congress fully fund local utility relocations, other local economic losses, and impacts of the project.

Long-Term Design of TH 36 Alternatives for the long-term design of TH 36 through Oak Park Heights and Stillwater may be evaluated through future studies. In August 2005, approximately $400,000 was allocated to Oak Park Heights as part of the federal surface transportation bill in support of additional studies for TH 36 through Oak Park Heights and Stillwater.1 The City of Oak Park Heights will lead the additional studies. Mn/DOT will work with both cities and Washington County to evaluate potential alternatives. Alternatives that could be evaluated include Concepts A through H, documented in the 2002 TH 36 Partnership Study Final Report, as well as other potential alternatives. Any future changes to TH 36 different than those described in this SFEIS will be evaluated through a separate environmental documentation process. 3.3.2.2 Preferred Alternative TH 36 Design The Preferred Alternative includes the Minnesota approach design (TH 36 between Washington/Norell Avenues and Osgood Avenue) approved with the 1995 FEIS. Revisions to the 1995 FEIS design between Washington/Norell Avenues and Osgood Avenue include: • South frontage road alignment has been revised to avoid a townhome complex at the

southwest quadrant of the intersection with Oakgreen Avenue;

• Stormwater basins have been incorporated along Oakgreen Avenue/Greeley Street between the north and south frontage roads to provide treatment for stormwater runoff;

• Trails have been added to both sides of Oakgreen Avenue/Greeley Street between the north and south frontage roads; and

• A trail has been added to the south frontage road between Oakgreen Avenue and Osgood Avenue.

1 Public Law 109-59. Safe, Accountable, Flexible, Efficient Transportation Equity Act – A Legacy for Users (SAFETEA-LU).


Municipal consent for the 1995 FEIS Preferred Alternative TH 36 improvements was granted by Oak Park Heights and Stillwater in 1995. Under the Preferred Alternative, the TH 36 mainline will be reconstructed from west of Oakgreen Avenue/Greeley Street through the new TH 36/95 interchange. No improvements will be constructed at Norell Avenue/Washington Avenue under the Preferred Alternative. A portion of the 1995-approved design at Washington/Norell was constructed in conjunction with the construction of the TH 36/TH 5 interchange.2 The Preferred Alternative consists of a four-lane urban section roadway with two through lanes for both eastbound and westbound TH 36 traffic. Three elements of the 1995 design have been modified for the Preferred Alternative east of Osgood Avenue: 1) the Beach Road overpass will be reconstructed along a new alignment; 2) an extension of the north frontage road between Osgood Avenue and TH 95 has been removed from the Preferred Alternative design; and 3) the south frontage road will be extended from Osgood Avenue to Stagecoach Trail. Construction of the Preferred Alternative on TH 36 will begin approximately 1,050 feet east of the Washington/Norell intersection with TH 36. The design features of TH 36 between Washington/Norell Avenues and Osgood Avenue for the Preferred Alternative are described below and illustrated in Figure 3-2. Typical sections of TH 36 and the north and south frontage roads are illustrated in Figure 3-5. The design features of the Preferred Alternative west of Osgood Avenue to the western project terminus are summarized below. • Construction of dual left-turn lanes on eastbound and westbound TH 36 at the Oakgreen

Avenue/Greeley Street and Osgood Avenue intersections;

• Reconstruction of Oakgreen Avenue/Greeley Street, including a raised median, between the pulled-back frontage roads to accommodate turn lanes at the TH 36 intersection and frontage road intersections. Reconstruction would extend beyond the pulled-back frontage roads to match the existing roadway alignments;

• Construction of stormwater ponds at the TH 36/Oakgreen Avenue/Greeley Street intersection;

• Widening of Osgood Avenue between the frontage roads and TH 36 to provide dual left turn lanes;

• Reconstruction of the north and south frontage roads as a three-lane section (two through lanes and a continuous left-turn lane) between the western project terminus east of Washington/Norell Avenues and Osgood Avenue. Reconstruction of the frontage roads will also include paved shoulders;

• Pulled-back north and south frontage roads at Oakgreen Avenue and Greeley Street. The Greeley Street/north frontage road and Oakgreen Avenue/south frontage road will be

2 Improvements previously constructed with the TH 36/TH 5 interchange construction include: double-left turn lanes from the TH 36 mainline to Washington/Norell; turn lane improvements on Washington/Norell to TH 36; and reconstruction of the north and south frontage roads as a three-lane section (two through lanes and a continuous left-turn lane) between TH 5 and Washington/Norell.


signalized intersections with dedicated turn lanes from the frontage roads to Oakgreen Avenue and Greeley Street; and

• Construction of trails at the Oakgreen Avenue/Greeley Street and Osgood Avenue intersections with TH 36, as well as a trail between Oakgreen Avenue/Greeley Street and Osgood Avenue along the south frontage road.

The design features of the Preferred Alternative east of Osgood Avenue to the TH 36/95 interchange are summarized below.

• Extension of the south frontage road east from Osgood Avenue to the relocated Beach Road

overpass and Stagecoach Trail;

• Residential streets east of the landfill will be realigned to intersect with Stagecoach Trail at T-intersections;

• Driveway access and side street connections to the north and south frontage roads will be reconstructed with the reconstruction of the frontage roads. Some existing driveway access to the frontage roads, Oakgreen Avenue/Greeley Street, and Osgood Avenue will be eliminated or consolidated with driveways at adjacent locations;

• Merging lanes will be provided for both eastbound and westbound TH 36 at the TH 36/95 interchange ramps (Figure 3-3);

• Closure of existing TH 36/Beach Road access; Beach Road will be converted to an overpass and realigned to the west, intersecting with the south frontage road at a T-intersection. This is a new element from the 1995 design, requested to connect lower and upper Oak Park Heights in place of a north frontage road, as was shown in the 1995 design. Because of development in the northeast quadrant of the Osgood Avenue/TH 36 intersection and the Beach Road realignment and overpass, the north frontage road extension between Osgood Avenue and TH 95 was not feasible; and

• North of Beach Road and the St. Croix Overlook-South, Lookout Trail will be reconstructed as a one-way southbound roadway, accommodating only a right-turn access from southbound TH 95. This segment of Lookout Trail is required to be a one-way roadway because steep grades result in safety and traffic operations concerns. The left turn to Lookout Trail from northbound TH 95 will be eliminated with the improvements to TH 95.

The design speed for the TH 36 mainline is 60 miles per hour (mph). The current posted speed for this segment of TH 36 is 50 mph. 3.3.3 TH 95 TH 95 will be reconstructed for approximately 3,050 feet north and approximately 3,550 feet south of the new TH 36/95 interchange (see Section 3.3.4). TH 95 will be realigned to the west for this reconstruction to accommodate the TH 36/95 interchange. Typical sections of TH 95 are illustrated in Figure 3-7. The Preferred Alternative has the following TH 95 features: • Two-lane urban section expanding to a four-lane urban section with a raised center median ;


• Turn lanes from TH 95 to the relocated entrances for the Sunnyside Marina and Condominiums and the Metropolitan Council Environmental Services (MCES) St. Croix Regional Wastewater Treatment Plant access;

• Realignment of the CSAH 28 (Pickett Avenue) intersection with TH 95 to the south (150 feet), consolidating access points on TH 95 with the Xcel Energy King Plant main entrance. If warranted, a signal may be installed at the intersection of TH 95, CSAH 28, and the King Plant entrance;

• Construction of turn lanes on both north- and southbound TH 95 at the CSAH 28 (Pickett Avenue) intersection;

• Removal of 56th Street between TH 95 west to the intersection with CSAH 28 (Pickett Avenue) for the construction of stormwater ponds;

• Construction of stormwater ponds east of TH 95 near the Sunnyside Marina and Condominiums access road and along TH 95 south of the TH 95/CSAH 28 intersection; and

• Construction of trail along TH 95 to connect local and regional trails. The design speed for TH 95 is 40 mph. The anticipated posted speed will be 40 mph, dependent upon the results of a speed study. The design concept for TH 95 is shown on Figure 3-3. The typical cross section for TH 95 is depicted on Figure 3-7. 3.3.4 TH 36/TH 95 Interchange Area The Preferred Alternative TH 36/95 interchange area has the following features: • Construction of a new standard diamond interchange with TH 36 and realigned TH 95;

• Ramps west of TH 95 will be constructed as rural section roadways. Ramps east of TH 95 will be constructed as urban sections with a curb and gutter. Ramps from TH 36 will include dedicated turn lanes at their intersection with TH 95;

• Signals, if warranted, may be constructed at the interchange ramp intersections with TH 95;

• Construction of stormwater ponds west of TH 95 between the ramps and the TH 36 mainline and north of the TH 95 to westbound TH 36 interchange ramp;

• Relocation of the Union Pacific Railroad lines within the TH 36/95 interchange area; and

• Construction of an anti-icing building (see Section 3.3.5.3 of this SFEIS) under the TH 95 northbound to TH 36 eastbound entrance ramp.

The TH 36/95 interchange layout is depicted in Figure 3-3. The typical sections for the TH 36/95 interchange ramps are depicted in Figure 3-6. 3.3.5 St. Croix River Crossing 3.3.5.1 River Crossing Location


The Preferred Alternative river crossing is located approximately 7,550 feet south of the Lift Bridge along the Minnesota shoreline and approximately 6,450 feet south of the Lift Bridge along the Wisconsin shoreline. The Preferred Alternative bridge would leave the Minnesota shoreline between the MCES St. Croix Regional Wastewater Treatment Plant and the Xcel Energy King Power Plant in Oak Park Heights and utilizes an existing ravine in the Wisconsin bluff. 3.3.5.2 River Crossing Bridge Type The proposed bridge type for the Preferred Alternative Package is an extradosed-type bridge design. An extradosed-type bridge consists of several shorter towers (relative to a cable-stay bridge-type design) with cables connected from the towers to the bridge deck (see Figure 7-6 and 7-7 of this SFEIS for photo simulations of the Preferred Alternative river crossing bridge). The bridge towers are anticipated to be approximately 200 feet to 235 feet above the river surface, or approximately 70 feet above the bridge deck. Final tower height will be determined in more detail through the visual quality process and finalized in the detailed bridge design. The anticipated maximum span length between bridge piers is 500 feet. Bridge concept plans anticipate four to six piers in the river. The location of approach bridge piers and extradosed bridge piers will be determined through the visual quality planning process (described in Section 7.4.3 of this SFEIS) and final bridge design. Characteristics of the Preferred Alternative river crossing are described below in Table 3-1. TABLE 3-1 PREFERRED ALTERNATIVE RIVER CROSSING CHARACTERISTICS

Preferred Alternative

Minnesota shore 113 feet Height of bridge deck above normal pool elevation(1) of the river Wisconsin shore 159 feet

Clearance above the two percent flow line(2) over the navigational channel(3) 120 feet(4)

Total bridge length (abutment to abutment) 4,953 feet

Bridge length over the river 2,840 feet

Bridge grade from Minnesota shore to Wisconsin shore 1.74% (1) Normal pool elevation of the river = 675 feet above mean sea level (msl). (2) Two percent flow line elevation = 684.3 feet above msl. (3) Assumes a bridge depth of 10 feet; exact bridge depth will be determined with final bridge design. (4) The location of the navigation channel was assumed to be the middle of the river. Three bridge types were considered in the SDEIS and during the Stakeholder process for the Build Alternative B-1 river crossing alignment: cable-stay; extradosed; and haunched concrete box girders (illustrations of these bridge types are located in Chapter 7 of the SDEIS). The extradosed bridge type was identified for the Preferred Alternative because this bridge type best balances the different perspectives of the three bridge types considered for the Preferred


Alternative river crossing alignment. Several areas of concern were considered in identifying the bridge type including visibility, height of towers, number of piers in the river and the effects of the piers on the natural environment, including wildlife, aquatic life, wetlands, and the Wisconsin bluffs. The extradosed bridge type is unique in that no extradosed type bridges have been constructed in the United States to date. Two extradosed bridges have been designed but not yet constructed. Only one of these (Q Bridge in Connecticut) is comparable in extradosed span length to the proposed St. Croix River Crossing; however, the Q Bridge will have only three extradosed spans whereas the proposed St. Croix River Crossing bridge is anticipated to have at least six extradosed bridge spans, with four to six piers in the Riverway. This unique bridge type introduces a new form and structural appearance to viewers and users both on and off the bridge. Viewers on the bridge will see details of the towers and cables at close range. Thus, the scale, proportion, materials and coloration of the towers and cables become important characteristics. The bridge approach span piers and the tower bases are concrete in material, presenting a wide variety of design opportunities in design details and surface treatments. Final project design will include an appropriate level of aesthetic enhancements (e.g., wall treatments; lighting; landscaping; railings) to be determined through the Visual Quality Planning Process and Visual Quality Manual development. The Visual Quality Planning Process and Visual Quality Manual development is described in Section 7.4.3 of this SFEIS. Final design of the bridge approaches will also employ traffic calming techniques (i.e., aesthetic enhancements described above), to the extent feasible, to transition drivers from the higher posted speeds in Wisconsin to the anticipated lower posted speeds in the Minnesota portion of the project. 3.3.5.3 Bridge Lanes and Geometrics The Preferred Alternative river crossing bridge will have the following features: • Pedestrian/bicycle trail on the north side of the bridge;

• Two travel lanes in both the eastbound and westbound directions; and

• Inside and outside shoulders; the inside shoulders will be separated by a center median barrier.

The design speed for the river crossing is 70 mph. The typical cross section for the Preferred Alternative river crossing is depicted on Figure 3-8. A fully-automated anti-icing system is anticipated to be constructed on the Preferred Alternative river crossing bridge, including the Minnesota and Wisconsin approach bridges. This system will require one pump house in Minnesota. The anticipated location for this building is within the TH 36/95 interchange. Access to the buildings will be provided from adjacent roadways. The buildings and their access roads will be located on Mn/DOT right-of-way. Details regarding the anti-icing system will be determined during final design. 3.3.6 Future Use of the Lift Bridge


As part of the Preferred Alternative package, the Lift Bridge will no longer carry vehicular traffic and will be converted to a pedestrian/bicycle facility and will be part of the loop trail system. The existing operations/lift schedule for the Lift Bridge will remain in effect with conversion of the Lift Bridge to a pedestrian/bicycle facility. The current lift schedule for the Lift Bridge is illustrated in Figure 4-8 of the SDEIS. The Lift Bridge will continue to be owned by the State of Minnesota but will be removed from the state trunk highway system following opening of the new river crossing to traffic. Mn/DOT will establish an endowment fund for future Lift Bridge operations and maintenance. The Stillwater Lift Bridge Advisory Committee (SLBAC) will be created to advise Mn/DOT and make recommendations regarding maintenance, repair, rehabilitation and management of the Lift Bridge during its interim vehicular use. The SLBAC will oversee the development of the Lift Bridge Management Plan to guide Mn/DOT in short- and long-term approaches to Lift Bridge operations, maintenance and preservation. Mn/DOT has committed to funding up to a $7 million rehabilitation project for the Lift Bridge (see the Amended Section 106 Memorandum of Agreement in Appendix G of this SFEIS). Plans to reconstruct the existing Lift Bridge approach in Minnesota will be coordinated with the City of Stillwater and will be implemented following completion of the new river crossing. Minor modifications will be implemented to Chestnut Street to prevent vehicular use of the Lift Bridge. This includes the construction of bollards, or a similar gating element, within the existing Chestnut Street right-of-way. The bollards will be removable to allow for maintenance and emergency vehicles to access the Lift Bridge and Kolliner Park in Wisconsin. There is also the opportunity to increase new parking along Chestnut Street. Refer to Section 5.3.1.2 of this SFEIS for a discussion of parking opportunities along Chestnut Street under the Preferred Alternative. 3.3.7 Wisconsin STH 64 The Preferred Alternative Wisconsin approach roadway will continue northeast from the bridge abutment, turn north near a section line to existing STH 35/64, then parallel the north side of the existing STH 35/64 alignment to 20th Street. The Preferred Alternative alignment will tie into the existing STH 35/64 alignment near 20th Street and continue northeast to the eastern project terminus near the 150th Avenue overpass. The Preferred Alternative will have the following features in Wisconsin from the river crossing to the eastern terminus near the 150th Avenue overpass: • STH 64 will be constructed as a four-lane urban freeway through the Wisconsin bluff to

existing STH 35 (see Figure 3-9);

• STH 64 will be constructed as a four-lane rural freeway east of the Wisconsin bluff to the project terminus near the 150th Avenue overpass;

• Existing STH 35 will be reconstructed as an overpass over the new STH 64 roadway east of the bridge abutment and Wisconsin bluff;

• Construction of a new, standard diamond interchange with a new STH 35 roadway and relocated CTH E. Traffic signals, if warranted, or roundabouts will be constructed at the


STH 35/CTH E ramp intersections. Inclusion of signals or roundabouts will be determined with final design;

• Reconstruction of CTH E to the south of the existing CTH E alignment to the new standard diamond interchange with the STH 64 mainline. Existing CTH E west of the interchange will be constructed as a cul-de-sac near the Houlton Elementary School;

• Construction of a new STH 35 roadway north of the overpass over the STH 64 mainline to the new interchange with STH 64. A typical roadway section for new STH 35 is illustrated in Figure 3-10. A traffic signal, if warranted, will be installed at the intersection of the new STH 35 roadway with existing STH 35. This intersection could also be constructed as a roundabout; the inclusion of a signal or roundabout will be determined with final design;

• Construction of a new local road between existing CTH E and the new STH 35 roadway just west of Houlton Elementary School; and

• Construction of stormwater ponds along the STH 64 mainline between STH 35 and 20th Street.

The existing STH 35 roadway will be converted to a local roadway north of the new STH 35 roadway described above. A new frontage road will be constructed north of the new STH 35/64 roadway while existing STH 35/64 will be converted to a south frontage road to serve local land access. No access to private property will be allowed from the new STH 35/64 roadway. Restricted access will be allowed on the reconstructed portion of CTH E and the new STH 35 roadway west of the interchange. The design speed for STH 64 in Wisconsin is 70 mph. The posted speed will be 65 mph. The layout of the Preferred Alternative in Wisconsin is illustrated in Figure 3-4. A typical section for the STH 64 mainline and STH 64/STH 35/CTH E interchange ramps is illustrated in Figure 3-9. 3.3.8 Identification of the Preferred Alternative Package The Preferred Alternative package was identified through a balanced decision-making process and negotiations as part of the Stakeholder Resolution Process, which considered the transportation purpose and need to provide safe and efficient mobility while considering the environmental, economic, social, and historic resource concerns present within the project area. The Preferred Alternative package best addresses these different perspectives and the responsibilities outlined in Section 101 of NEPA.3 The primary reasons considered in identifying Alternative B-1a (conversion of the Lift Bridge to a pedestrian/bicycle facility) as the Preferred Alternative location are summarized below. • The proposed four-lane river crossing provides sufficient capacity to meet forecasted year

2030 travel demand; with sufficient excess capacity to meet additional travel demands

3 Section 101 [42 USC § 4331] of the National Environmental Policy Act of 1969 (NEPA).


beyond 2030. The four-lane crossing also reduces diversion of traffic to the I-94 St. Croix River Crossing, thereby addressing capacity concerns at that crossing as well.

• The proposed alignment lies far enough south of downtown Stillwater to remove a substantial number of regional through trips from downtown streets, thereby reducing congestion.

• Construction of a new river crossing for both directions of traffic eliminates concerns regarding the structural condition, geometric restrictions and reliability associated with the existing river crossing.

• Construction of a new river crossing and elimination of vehicular use of the Lift Bridge will also eliminate traffic congestion in downtown Stillwater resulting from bridge raisings.

In addition, the Stakeholder Group-developed purpose and need identified a number of environmental, economic, social, and historic resource concerns that should be avoided or minimized by the project. Alternative B-1a best addresses these concerns as noted below. • The proposed roadway alignment avoids and/or reduces direct impacts to National Register

of Historic Places listed or eligible properties, as it is the farthest in distance from the Lift Bridge, the Stillwater Commercial Historic District, and the Stillwater Cultural Landscape District. Alternative B-1a also avoids use of contributing sites within the Landscape District, including the Hersey and Bean site in the Stillwater South Main Street Archaeological District, and the Tourist Camp and Legion Park sites in Kolliner Park.

• The Alternative B-1a alignment avoids substantial right-of-way taking from local parks (Section 4(f) resources) including the Stillwater Municipal Barge Facility property, Lowell Park, and Kolliner Park.

• The Alternative B-1a alignment minimizes impacts to the Lower St. Croix National Scenic Riverway by minimizing river crossing distance through an alignment more perpendicular to the river centerline (as compared to the 1995 FEIS Preferred Alternative) and by constructing a new river crossing in an area previously disrupted through construction of a water treatment facility and an electrical generating plant.

• Conversion of the Lift Bridge to a pedestrian/bicycle facility under Alternative B-1a allows the new river crossing project to be compatible with the Lower St. Croix Management Plan and Lower St. Croix Management Commission policy of “non-proliferation” of transportation crossings and the historic Lift Bridge to be preserved as a recreational amenity.

Other Resource Issues • Fewer contaminated sites are affected under Alternative B-1a. Although all alternatives

potentially affected roughly the same number of medium-risk sites, Alternative B-1a would potentially affect six high-risk sites, compared to nine sites under the other alternatives.

• All alternatives exerted similar impacts on protected species, the fish and aquatic community, the terrain and climate, and wildlife. Alternative B-1a resulted in less removal of trees and undergrowth along shorelines and upland/bluff areas, with the amount estimated at


2.18 acres. Other alternatives required removal of 3.98 to 13.29 acres of trees and undergrowth.

• Impacts were the same for all alternatives for water quantity (drainage), water quality and groundwater. Alternative B-1a resulted in substantially less longitudinal impact (900 feet) and no transverse impact to the 100-year floodplain from road and pond construction, compared to other alternatives that ranged from 1,600 to 5,400 feet of longitudinal and additional transverse impacts to the 100-year floodplain.

• Alternative B-1a would also impact the fewest acres of wetlands, with a total of 6.37 acres affected.

Since publication of the SDEIS, Alternative B-1a has been refined (e.g.; TH 36 design; drainage design in Wisconsin) to address environmental, right-of-way, and other concerns and to incorporate elements of the Preferred Alternative package (e.g., loop trail mitigation item). Additional benefits of the Preferred Alternative package include: • Use of the “1995 layout” in the Osgood to TH 5 segment avoided a substantial number of

commercial property takings in the cities of Oak Park Heights and Stillwater while improving short term traffic operations and safety concerns in this segment of TH 36. The cities of Oak Park Heights and Stillwater will continue working toward long-term operations improvements that will address the cities’ right-of-way and economic concerns in this segment.

• The Preferred Alternative package minimizes impacts to the Riverway through identification of the extradosed type bridge and profile that minimizes bluff disturbance, reduces the number of piers in the river, and allows for an aesthetic design compatible with the character and importance of the Riverway.

However, these modifications (e.g., 1995 TH 36 layout; loop trail mitigation item) have resulted in some impacts (e.g., wetlands; floodplains), as described in the following SFEIS chapters, to be greater than the Alternative B-1 impacts described in the SDEIS. If these same modifications were equally applied to the other SDEIS Build Alternatives (Alternatives C, D, and E), their impacts would also increase in the same amount as the increase experienced with the Preferred Alternative package under Alternative B-1. Therefore, although some impacts have increased under the Preferred Alternative package, the Preferred Alternative package still best addresses the transportation purpose and need to provide safe and efficient mobility while considering the environmental, economic, social, and historic resource concerns present within the project area. Comparison to 1995 FEIS Preferred Alternative As noted in Section 1.2.4.5 of this SFEIS, FHWA previously approved a Final EIS and Section 4(f) Evaluation for a new St. Croix River crossing approximately 6,300 feet south of the Lift Bridge. A Record of Decision for the 1995 FEIS Preferred Alternative was issued by FHWA in July 1995. Work on this alternative was later halted after a determination from the NPS that the 1995 FEIS Preferred Alternative would have a direct and adverse effect on the outstandingly remarkable values for which the Lower St. Croix River was included in the National Wild and Scenic Rivers System.


The Preferred Alternative identified by Mn/DOT and WisDOT in this SFEIS is substantially different from the 1995 FEIS Preferred Alternative for the following reasons: • Extradosed bridge design. The Preferred Alternative extradosed bridge design was

identified because it best balances areas of concern related to bridge type. The extradosed bridge type reduces apparent mass of the structure by reducing the number of piers in the water and the height of structures above the bridge deck.

• River crossing alignment. The Preferred Alternative river crossing alignment is more perpendicular to the Riverway compared to the 1995 FEIS Preferred Alternative, resulting in less bridge structure over the St. Croix River and fewer piers in the Riverway.

• Number of piers in the river. The Preferred Alternative will have 4 to 6 piers in the river, whereas 8 piers would have been constructed in the river for the 1995 FEIS Preferred Alternative. Fewer piers in the river results in less obstruction for recreational boaters on the St. Croix River and less disturbance to the Riverway during bridge construction.

• St. Croix River mussel habitat. The Preferred Alternative extradosed bridge design will allow for the 200-foot mussel shelf along the Wisconsin shoreline to be spanned by the bridge structure, avoiding impacts to this aquatic habitat.

• Xcel Energy barge unloading facility. Under the Preferred Alternative, the Xcel Energy barge unloading facility will be used for barge docking and staging for construction of the river crossing prior to its eventual removal from the Riverway. The re-use of this existing facility for the river crossing project avoids the placement of a temporary barge docking facility that would otherwise be constructed in the river if the Xcel facility were not present.

• Mitigation items. The Preferred Alternative mitigation package (see Section 15.4 of this SFEIS) includes a number of items to offset the impacts of a new river crossing on the unique and outstanding values of the Lower St. Croix Riverway.

• Lift Bridge. Under the 1995 FEIS Preferred Alternative, the Lift Bridge was to remain open to vehicular traffic. The disposition of the Lift Bridge would be determined at an appropriate time in the future whenever a change in operations, maintenance, or jurisdiction was deemed prudent by Mn/DOT and WisDOT. Under the Preferred Alternative described in this SFEIS, the Lift Bridge will no longer carry vehicular traffic and will be converted to a pedestrian/bicycle facility into perpetuity.

3.4 RIGHT-OF-WAY Additional right-of-way will be required for the Preferred Alternative package; right-of-way impacts will be minimized to the extent possible. Anticipated right-of-way acquisition areas are described and depicted in Section 5.2 of this SFEIS. Previously acquired right-of-way in Minnesota along the 1995 FEIS Preferred Alternative alignment will be utilized for the TH 36/95 interchange; none of this previously acquired right-of-way will be available for redevelopment following construction. Previously acquired right-of-way in Wisconsin along the 1995 FEIS Preferred Alternative alignment will be utilized for the STH 64/35//CTH E interchange and new STH 35/64 roadway north of CTH E. Lands west of


existing STH 354 and lands east of existing STH 35 to the proposed STH 64/35/CTH E interchange area will be available for resale following construction. Refer to Section 15.4.1.2 of this SFEIS for additional discussion of excess property in Wisconsin.

3.5 PROJECT COST

Funds from various federal, state, and local funding sources are anticipated for this project. Minnesota and Wisconsin will fund its respective approach roadway costs while the cost of the river bridge and other project related items will have varied combinations of Minnesota and Wisconsin funding. Approximately $25 million was allocated between Minnesota and Wisconsin for the St. Croix River Crossing Project as part of the 2005 federal surface transportation bill. The overall anticipated project construction cost is presented below.

3.5.1 Cost Estimate Review Workshop

In August 2005, FHWA, Mn/DOT, and WisDOT staff, led by a consultant, participated in a cost estimate review for the St. Croix River Crossing Project. The purpose of this review was to verify the accuracy and reasonableness of the project cost estimate and to develop a cost estimate range that considered the level of uncertainty and risk remaining given the current state of the Preferred Alternative design. The outcome of the review was a report that documented the cost estimate range for the Preferred Alternative. 5

3.5.2 Cost Estimate Review Workshop Findings

In summary, the cost estimate review workshop included an assessment of the project scope and the costs of the various construction and non-construction elements based on the Preferred Alternative. The next step in the review evaluated the project risks that could impact costs. The review concluded that the river crossing bridge, aesthetics, and constructability were the primary factors contributing to the risk associated with the project cost. The high level of risk associated with the river crossing bridge construction, particularly on the main spans, was due to the Preferred Alternative extradosed bridge type. A probability range of bids was then applied to the cost estimate to obtain the range of costs.

The cost estimate review concluded that the project cost range, for 10 percent to 90 percent probability, is $299 million to $334 million dollars (2004 dollars). When project risks were considered, and a 100 percent bid probability, the project cost estimate approached $373 million (2004 dollars) (the 100 percent probability mark at the right of the curve in Figure 3-11). These costs are illustrated in the curve in Figure 3-11 below.

4 Lands west of existing STH 35 at the former WisDOT wayside south of the project and along the 1995 Final EIS Preferred Alternative alignment. 5 St. Croix River Crossing Cost Estimate Review. February 2006. Prepared by PBS&J for Federal Highway Administration. 98 pp.


FIGURE 3-11 “2004” TOTAL COST ESTIMATE REVIEW – PROBABILITY ASSESSMENT

As documented in the Cost Estimate Review Workshop Report:

This curve [Figure 3-11] demonstrates the summary of the probabilities determined by the Team based on each of the individual project components. It demonstrates that if the project was bid today, the Team considers that there is a 10 percent probability the bid would be below $299 million, an 80 percent probability that the bid would be between $299 million and $334 million, and a 10 percent probability that the bid would be above $334 million. Also noted in the bottom of the chart is the Team’s recommended Estimate Review without risk of $317 million.

To properly estimate the project costs in future year dollars for programming purposes, the review estimated an inflation rate of 3 percent per year to the projected midpoint of project expenditure (year 2010) and recommended including a contingency for potential changes during construction. This resulted in an estimated year of expenditure total project cost range of $410 million to $453 million (year 2010 dollars). These costs are illustrated in the curve in Figure 3-12 below.


FIGURE 3-12 “2010” TOTAL COST ESTIMATE REVIEW – PROBABILITY ASSESSMENT

As documented in the Cost Estimate Review Workshop Report:

This curve [Figure 3-12] demonstrates the summary of the probabilities determined by the Team for each of the project components, including inflation, construction contingency and management reserve. It demonstrates the Team considers that there is a 10 percent probability the bid would be below $410 million, an 80 percent probability that the bid would be between $410 million and $453 million, and a 10 percent probability that the bid would be above $453 million. Also noted on the chart are the Team’s recommended Estimate Review without risk of $412 million (bottom of the chart) and the Team’s recommended Estimate including risk of $484 million (the 100 percent mark to the right of the chart).

The recommended [r]ange of the current Cost Estimate Probability in the mid-80 percent certainty level is noted as follows:

Estimate Estimate range in the mid

80 % probability (with risk) Total Project Estimate

(with risk) 2004 Base $299 M to $344 M $373 M 2010 Programming $410 M to $453 M $484 M

The results of the cost estimate review are summarized in Figure 3-13 in this SFEIS.


Figure 3-1 – SDEIS River Crossing Alternatives (8.5x11 – color)


Figure 3-2 – Preferred Alternative – TH 36 to Osgood Avenue (11x17 – color)


Figure 3-3 – Preferred Alternative – TH 36/95 Interchange Area (11x17 – color)


Figure 3-4 – Preferred Alternative – Wisconsin Alignment (11x17 – color)


Figure 3-5 – TH 36 typical sections (8.5 x 11, b/w)


Figure 3-6 – Typical Sections, TH 36/95 interchange ramps (8.5x11, b/w)


Figure 3-7 – Typical sections, TH 95 (8.5x11, b/w)


Figure 3-8 – Typical Section, Preferred Alternative River Bridge (8.5x11, b/w)


Figure 3-9 – Typical Sections, STH 64 (8.5x11, b/w)


Figure 3-10 – Typical Sections, STH 35 (8.5 x 11, b/w)


Figure 3-13 – Cost Estimate Review Summary (8.5 x 11, color)

Documents

ST. CROIX RIVER CROSSING PROJECT SUPPLEMENTAL ......CHAPTER 3 PROPOSED PROJECT – IDENTIFICATION OF THE PREFERRED ALTERNATIVE 3.0 INTRODUCTION This chapter describes the Preferred