DRAFT PURPOSE AND NEED STATEMENT 1 Background The Minnesota Department of Transportation (MnDOT) and the Wisconsin Department of Transportation (WisDOT) have initiated the planning for improvements to the Blatnik bridge. See Figure 1 for project location. MnDOT will act as the lead agency for the development, design and construction of the Blatnik Bridge (I-535) per the border bridge cooperative agreement with WisDOT. FHWA is the lead federal agency responsible for approval of the National Environmental Policy Act (NEPA) process and documentation for this project. The environmental processes and requirements of the state of Minnesota will be followed; however, Wisconsin state laws and regulations, and additional environmental processes apply to project activities proposed within the state of Wisconsin. MnDOT and WisDOT are working cooperatively in the planning, design and decision-making for this project as they have been for the inspection and maintenance of the structure. All studies and reports completed for the bridge are coordinate between both agencies. Both DOT’s include the Blatnik bridge in their respective plans for major bridge improvements starting in 2028. This agreement requires a 50/50 cost share for all border bridges. The John A. Blatnik Bridge (Minnesota Bridge 9030, Wisconsin Bridge B-16-5, hereafter called the Blatnik Bridge) on Interstate 535 (I-535) connects the two communities of Duluth, Minnesota, and Superior, Wisconsin across the St. Louis Bay. It is one of two bridges that connect the two communities (collectively called the Twin Ports) over the waterway. The other is the Richard I. Bong Memorial Bridge on U.S. Route 2 (US 2) to the southwest (hereafter called the Bong Bridge). The Blatnik Bridge is 7,975 feet long (about 1.5 miles) and consists of a main truss unit (three span continuous truss) flanked by steel beam approach span units (referred to as the Minnesota and Wisconsin approach spans), with a total of 52 spans. 1 The main truss span unit is 1,140 feet long with a 600-foot long center span over the main navigation channel and includes spans 16, 17, and 18 supported on piers 15 through 18. 2 The Minnesota approach spans are 2,019 feet long and include spans 1 through 15. The Wisconsin approach spans are 4,816 feet long and include spans 19 through 52. The U.S. Coast Guard has jurisdiction over structures spanning navigational channels, including the main truss over the navigational channel and the Wisconsin approach spans over Howard’s Pocket, a side channel. As originally designed, the bridge was able to accommodate the Routine (Annual) Permit vehicle weight of 154,000 pounds (lbs), from its opening in 1961 through 2007. 1 A span is the segment of a bridge between two piers or a pier and an abutment 2 A bridge pier is a vertical loadbearing member such as an intermediate support for adjacent ends of two bridge spans BLATNIK BRIDGE SP 6981-26 February 23, 2021 1 DRAFT PURPOSE AND NEED STATEMENT Figure 1: Blatnik Bridge Project Location BLATNIK BRIDGE SP 6981-26 February 23, 2021 2 DRAFT PURPOSE AND NEED STATEMENT Figure 2: Blatnik Bridge today (52 total spans, 3 truss spans and 49 approach spans) The Blatnik Bridge serves as a local, regional, and international connection for vehicle and freight traffic on I-535 / U.S. Highway 53 (US 53) between Minnesota and Wisconsin. The corridor has been identified as a designated route in several transportation studies due to its importance for vehicle and freight mobility, including: • Federal Highway Administration (FHWA) High Priority Corridor program, Corridor No. 41 (Falls to Falls Corridor; International Falls, MN to Chippewa Falls, WI) • Wisconsin Connections 2030 Long Range Multi-Modal Transportation Plan, “backbone” route • Duluth-Superior Metropolitan Interstate Council (MIC) Long Range Transportation Plan, major trunk line or main supply line • Metropolitan Interstate Council Duluth-Superior Area Truck Route Study 2018 Update, designated truck route The Blatnik Bridge serves a regionally important role for long-distance freight and vehicle traffic. The Blatnik Bridge sits at the epicenter of the Port of Duluth-Superior, which accommodates the maritime transportation needs of a wide range of industries including agriculture, forestry, mining and manufacturing, construction, power generation, and passenger cruising. It is also crucial to maintaining local mobility. During routine maintenance or in the event of a lane closure or blockage on the Blatnik or Bong Bridge, traffic reroutes from one to the other, thus the two crossings are essential to access between the two communities. Construction of the Blatnik Bridge began in 1958, and it was opened to traffic in 1961, replacing the original movable interstate bridge. The Blatnik Bridge has required expansion, safety modifications, and increasing maintenance frequency in order to maintain its serviceability. • In 1973, the raised median along the centerline of the bridge (separating opposing traffic) was replaced with a traffic barrier to improve safety. • In 1994, the approach spans were widened to accommodate an entrance ramp on the Minnesota approach and to increase the outside shoulder width to 8 feet on the Minnesota and BLATNIK BRIDGE SP 6981-26 February 23, 2021 3 DRAFT PURPOSE AND NEED STATEMENT Wisconsin approach spans. The widening was accomplished primarily by extending the existing pier caps to support additional beams and the concrete deck while utilizing the reserve capacity in the original columns and foundations (piers 8 through 14 and piers 19 - 51). Portions of the Minnesota approach spans included additional columns and foundations to support the widened entrance ramp (piers 1 through 7). The main truss spans were extensively rehabilitated to repair or replace deteriorated truss elements and the entire bridge deck was replaced. Due to the structural complexity of the truss unit, the truss spans were not widened, nor were the piers that support the main truss spans (piers 15 through 18). • In 2008, the truss span unit underwent emergency repairs for floor beam gusset plates. • In 2010, select cable suspender ropes on the main truss spans were removed and replaced to complete a laboratory condition assessment of undetected corrosion within a representative sample of the cable suspender ropes. • In 2012, the bridge expansion joints were replaced and the entire bridge was repainted. • In 2012, 2015, and 2016, additional repairs were made to the gusset plates and floor trusses of the truss unit. Overall, the bridge today requires a yearly inspection and structural maintenance at frequent intervals (approximately every four years for safety and serviceability). The next major maintenance project is scheduled for 2022 and is planned to include modifications to the existing bridge deck drainage system, concrete deck crack sealing, select concrete substructure repairs, sealing of the post-tensioned concrete pier caps, and selective spot painting with a focus on continued preservation. In addition to ongoing maintenance, the truss spans of the Blatnik Bridge are non-redundant, meaning if any one member of the truss fails, the bridge is not functional. In 2018, MnDOT began an existing bridge assessment, including a load rating analysis and subsurface pile investigation to examine the existing condition of the bridge. The 2018 study is set to be completed in 2021. Additionally, in 2017, WisDOT and the City of Superior completed a Safety and Operational Study of US 53 on the Wisconsin side of the Blatnik Bridge. 3 These studies establish the existing bridge and traffic operation conditions and provided a baseline for the development of the project needs. Geometric deficiencies in the bridge design and access interchanges along with adverse weather conditions influence poor traffic operations during peak periods and contribute to a high critical crash history. The unique setting of I-535 terminating in a neighborhood in Wisconsin complicates the traffic operations in the nearby local road network. 2 Needs Analysis MnDOT, in cooperation with WisDOT, has identified a number of factors justifying the need for the Blatnik Bridge project. The needs have been categorized as primary or secondary as defined below. Primary needs include the primary transportation problems in the project corridor. Three primary needs have been identified: • Bridge condition • Vehicle safety 3 Additional traffic operations data and analysis can be viewed in WisDOT’s US 53 Study, Safety, and Operations Summary (project 1198-03-06), September 25, 2017. BLATNIK BRIDGE SP 6981-26 February 23, 2021 4 DRAFT PURPOSE AND NEED STATEMENT • Vehicle mobility Secondary needs are other transportation problems that may be able to be addressed at the same time as primary needs. One secondary need has been identified: walkability/bikeability. 2.1 Bridge Condition The Blatnik Bridge is identified by both MnDOT and WisDOT as a high priority improvement project. The bridge is ranked number 1 by MnDOT for risk of service interruption. These rankings are based on a risk analysis that considers the high probability of service interruptions (based on deterioration, condition, load rating restrictions) combined with high consequences for service interruptions (traffic volume, route and classification, length of bridge). The Blatnik truss span is nearing the end of its service life (Year 2030) and, as a result, is weight restricted to 80,000 lbs and has maintenance and preservation needs that require extensive ongoing investment. The approach spans are also weight restricted and have maintenance needs that will require extensive investment over the next 25 years; 2045 is the projected design life of the approach spans. To prepare for and identify when bridge investments will be needed, MnDOT uses the Bridge Replacement and Improvement Management (BRIM) tool to forecast future work types, costs, and schedules for a 20-year planning horizon. BRIM provides several measures that are used to help prioritize investments and improvements for MnDOT for the planning horizon. These include: Bridge Planning Index (BPI), BRIM BPI Rank, and Project Selection Policy (PSP) Score.