MINNESOTA ARCHITECTURE - HISTORY INVENTORY FORM

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1 Identification Historic Name Iron Wagon Bridge; Bridge 7965 Current Name Coffee Street Bridge Field # Address Ped over South Branch of the Root River City/Twp Lanesboro County Fillmore County Legal Desc. Twp 103N Range 10W Sec 13 QQ NWSE USGS Quad Lanesboro SHPO Inventory Number Review and Compliance Number Form (New or Updated) Description Linear Feature? No HPC Status Unknown Resource Type Structure Architect/Engineer Chicago Bridge Co. Style None UTM Zone 15 Datum 27 Construction Date 1893; 2002 (rehabilitation) Easting Northing Original Use Transportation Property ID (PIN) Current Use Transportation Description Bridge 7965, also commonly called the Coffee Street Bridge or the Iron Wagon Bridge, is a single-span, steel, pinconnected, Pratt through truss with a steel-stringer approach span. 1 It is located in Lanesboro, Minnesota. Constructed in 1893 as a wagon bridge, the bridge now carries pedestrian and bicycle traffic on a northwest-southeast alignment over the South Branch Root River. The bridge is owned by the City of Lanesboro. Downtown Lanesboro is located to the east of the bridge and a city parking lot is located to the west. The overall structure length, including the approach span, is 139 feet. The truss span length is 119 feet, with an out-to-out deck width of 16 feet. The main span truss superstructure is comprised of seven panels in a Pratt configuration with riveted built-up members. The top chord and inclined endposts are paired back-to-back channels with top plate and V-lacing. The verticals are back-to-back channels with V-lacing on both sides. Diagonals are paired punched eyebars, except the two center panels, which have paired eyerods with turnbuckles. Top lateral bracing members are round-rod diagonals; struts are paired angles. Portal bracing is comprised of angles. Original ornamental metal plates identifying the construction date and bridge builder are mounted atop each portal. Floorbeams and stringers are rolled I-beams. The floorbeams are stamped Jones & Laughlin and are connected to the truss verticals with riveted plates. In 2002 the current wood-plank deck was installed, along with the current 4-1 The bridge is currently owned and maintained by the City of Lanesboro. Its state designation as 7965 no longer applies because it is no longer owned and maintained by the state; however, the bridge historically was known by this number and as such will be used throughout this report.

2 foot-6-inch-high pedestrian railing, which is mounted on the deck and separate from the truss members. The original two-angle railing was removed from the truss (railing bolt-holes are visible in the endposts and verticals). There is one 20-foot-long steel I-beam approach span at the northeast end of the bridge. Historically, the bridge had one approach span to the northeast (although historic photos are unclear about the northeast approach) and four short approach spans to the southwest. At an unknown date (possibly in the 1940s, based on historic photos) the four southwest approach spans were removed and replaced with earth infill. The removal of the original approach spans altered the function of the original substructure. The original limestone pier at the southwest end of the bridge now serves as the abutment for the truss; the northeast end of the truss is supported on original steel caissons. The northeast approach span, which extends from the caissons to the limestone abutment, was rebuilt in At the same time, concrete was added between the limestone pier cap and stringers at both ends. The truss span has original fixed bearings on the caissons and expansion bearings on the southwest limestone pier/abutment. Modern metal plates have been added outside the expansion bearings to restrict lateral movement. In 2002 non-historic light standards were installed just beyond both bridge approaches, along with additional railings and a walkway. A utility pipe, mounted on steel brackets bolted above the northwest lower chord, was added between 1942 and 1948 based on historical photographs. EVALUATION AND ANALYSIS Historical Context Iron and Steel Bridges in Minnesota, Historical Narrative Bridge 7965 was constructed in 1893 for the village of Lanesboro, a community nestled into the Mississippi Valley along the Root River. In 1863 a group of New York businessmen purchased about 3,000 acres of land for the future townsite. The investment group, named the Lanesboro Townsite Company, hoped to create a new scenic village. Quickly, Lanesboro became a bustling resort community supported largely by tourism, the Southern Minnesota Railroad, and a flour mill powered by a large limestone dam. Evidence of the rapid expansion of Lanesboro is attested by the 68-percent growth in population, from 1,063 to 1,600 residents between 1860 and The village boasted a hotel, school, three churches, four general stores, harness shop, eight saloons, and fairgrounds. The community built a number of wagon and railroad bridges to span the South Branch of the Root River, which snaked through the middle of Lanesboro, and the flour dam s tailrace. One such crossing was at Second Street (now Coffee Street). As reported in The [Lanesboro] Journal, in 1893, Fillmore County and the board of town supervisors met and approved a motion to build a new bridge over the River on Second Street. It is uncertain why the old bridge needed to be replaced; however, a newspaper article hoped that the new iron bridge would stay by us longer than the other one did, indicating the former crossing may have been washed away or destroyed somehow (see Figure 1). The township board awarded the bridge contract to the Chicago Bridge Company with a bid of $3,400. Materials for the bridge s construction, including the steel truss members and embankment riprap, arrived by rail in August. The Chicago Bridge Company completed construction of the main span in September at a cost of $3,500.

3 According to The [Lanesboro] Journal, the structure presents a very substantial and solid appearance and is very creditable to the township. By the end of the month the approaches were completed using third cords of stone and several hundred loads of dirt. The bridge provided wagon and pedestrian crossing over the river at a northeastsouthwest alignment (see Figures 2-3). In the early 1900s the bridge was given the state bridge number 7965 because it carried County Highway 8. In addition to it being known as this number until 2002, when the bridge underwent rehabilitation as a pedestrian bridge, it is also locally called the Iron Wagon Bridge and the Coffee Street Bridge. Few changes have been made to the bridge. In the 1940s a utility pipe was added to the north elevation; at an unknown time the steel I-beam approach spans to the southwest were removed (see Figure 4). The bridge continued to serve vehicular traffic for many years. By the early 2000s the bridge was in need of substantial rehabilitation. A local organization called the Coffee Street Bridge Enhancement Group approached the city to rehabilitate the bridge as a pedestrian bridge between downtown and the Bass Pond parking lot. The proposed rehabilitation had support from local citizens and the Lanesboro Chamber of Commerce, as reported in the Fillmore County Journal, that rehabilitation would enhance Lanesboro s theme of historic preservation and provide a new gateway to the community. Rehabilitation costs were reported to be $275,800, with the city contributing 20 percent of the costs and engineering fees to the project. The remainder of the needed funding was made up through fund-raising efforts and a grant. In April 2002 the citizens of Lanesboro voted on a 15-year general obligation bond to pay for a portion of the city s funding responsibility. The bonding bill passed and rehabilitation efforts began soon after. The firm of WHKS of Mason City, Iowa, was awarded the rehabilitation design. As part of work efforts, the original railing was removed and replaced with a new metal rail. A wood deck was installed and decorative lighting added to either end of the bridge. The northeast approach span steel I-beams were replaced and new concrete cap were added to the stone abutments. The bridge was repainted, including the original bridge plate, which reads 1893 Chicago Bridge Co. (see Figure 5). Rehabilitation work was completed in Significance Bridge 7965 was previously identified, in 1980, as part of the statewide bridge reconnaissance survey; however, it was not formally evaluated. Additionally, the bridge was identified by the Lanesboro Historic Preservation Commission as having possible historical significance under the local historic context of Industry and Agriculture, but additional evaluation and assessment were needed. As such, the following is the evaluation of Bridge The bridge is being evaluated under the Iron and Steel Bridges in Minnesota, Multiple Property Documentation Form (MPD). According to the MPD, a bridge may be eligible for the National Register of Historic Places (National Register) under Criteria A, B or C. A steel bridge may be eligible under Criterion A for its association with events related to transportation, settlement, or development that contribute to broad patterns in American, Minnesota, or local history. Research did not reveal that Bridge 7965 was associated with increased settlement or further development of Lanesboro because Lanesboro was already a well-established resort community at the time the bridge was constructed. Bridge 7965 replaced an earlier bridge and therefore does not reflect new transportation routes to or from the city. As such, Bridge 7965 is not recommended eligible under Criterion A.

4 A bridge may also be eligible under Criterion B if it is associated with an important individual, if that individual was not the designer or builder of the bridge (this association would be considered under Criterion C as a work of a master). Research did not reveal any association with an important local, regional, state, or national individual during the life of the bridge. The bridge is recommended not eligible under Criterion B. To be eligible under Criterion C the bridge must meet one or more registration requirements defined in the MPD. Bridge 7965 meets the MPD Registration Requirement 2, which states, Built during the 1890s. Such bridges are probably steel and represent the first extensive use of this material for bridge construction in Minnesota. They are quite rare. Bridge 7965 is one of four known truss bridges constructed in the 1890s. Other examples include Bridge 6263 (1899) in Fillmore County, Bridge (1899) in Meeker County, Bridge L5573 (1894) in Steele County, and Bridge L6322 (1895) in Olmstead County. Constructed in 1893, Bridge 7965 is the oldest known extant through truss likely constructed of steel in Minnesota. As such, it meets the MPD Registration Requirement 2. The period of significance for Bridge 7965 is 1893 to correspond with its date of construction. Bridge 7965 is located outside of the National Register-listed Lanesboro Historic District (listed in 1982). The district consists of commercial properties fronting Parkway Avenue between Hillcrest and Coffee Streets. The period of significance is While the bridge fits within the defined period of significance, the bridge is not contiguous with the boundary of the historic district. There are buildings of more recent construction between the historic district and the bridge s location. As such, the bridge is not included within the boundary of the Lanesboro Historic District. Re-evaluation of district boundaries and contributing and noncontributing properties is outside of the scope of the project; however, if district boundaries were redrawn to include additional commercial properties, Bridge 7965 could be a contributing resource to the district. Integrity As defined in the MPD, a bridge s superstructure is the most important part of the bridge and must be in substantial original condition in order for it to retain integrity. This includes original connections, composition, and configuration. However, alterations to the substructure, original deck, guardrail system, and rail are described as having a minor impact to integrity. Bridge 7965 has undergone minor modification since its construction. At an unknown time a metal utility pipe, supported by steel brackets, was installed along the north elevation of the truss. In the 1940s the original bridge approaches to the southwest and northeast were removed. In 2002 the bridge underwent rehabilitation and conversion to a pedestrian bridge. Repairs included installing a new wood deck to replace the non-historic concrete deck that was in place, stabilization of the stone abutments, repainting the structure, and replacing the original rail with a new steel railing. Decorative lighting was installed at either end of the structure. The rehabilitation was not subject to Section 106 consultation since the work was not funded with federal money. The repairs and alterations that have occurred are modest and have not altered the original configuration, design, or composition of the truss. The addition of the utility pipe and new railing are reversible and do not significantly alter the truss superstructure. Abutment repairs, including the addition of concrete atop the stone, is also considered a minor modification as the repairs do not distract from the superstructure. The rehabilitation was sensitive to original materials and the original design of the structure. As such, the bridge retains integrity of workmanship, design, and materials.

5 Bridge 7965 continues to span the Root River in northwest Lanesboro in its original location. The commercial downtown is adjacent to the east and open park land to the west, much in keeping with the original setting of the bridge. While the bridge no longer carries vehicular traffic, the bridge continues to provide a form of transportation over the river between downtown Lanesboro and the edge of town. As such, the bridge retains integrity of setting, association, location, and feeling. Recommendation Bridge 7965 is eligible for listing in the National Register under Criterion C: Engineering as an example of the evolution of its bridge type. The bridge meets Registration Requirement 2 of the Iron and Steel Bridges in Minnesota, MPD and is a representative example of an early steel truss bridge in the state. Despite rehabilitation and conversion to pedestrian use in 2002, the bridge continues to convey its significance. Sources Bridge 7965 Minnesota Architecture/History Inventory Form. Available at the State Historic Preservation Office, Minnesota Architecture/History vertical files, Fillmore County, St. Paul, Minn. Drake, Charles and Vienna. River Valley Echoes: Lanesboro, Rochester, Minn.: Whiting Printers & Stationers, Historic Photographs of Bridge Available at the Lanesboro Museum, photograph collection, Lanesboro, Minn. Lanesboro Timeline. Available at the Lanesboro Museum, general collection, Lanesboro, Minn. Todd, David, Lanesboro City Administrator. Interview by Mead & Hunt, Inc., 29 July Thomas Zahn & Associates. City of Lanesboro Downtown Preservation Commercial Design Guidelines. Prepared for the Lanesboro Heritage Preservation Commission (Summer 2012). Newspapers Fillmore County Journal, 2002, 2014 The [Lanesboro] Journal, 1893 Consultant s Recommendation of Eligibility Eligible (Individually) Prepared By Mead & Hunt, Inc. Date Surveyed 29 July 2014

6 Property Photographs Southwest elevation and portal of Bridge 7865, view facing northeast. Northeast elevation of Bridge 7965, view facing east-southeast.

7 Downtown Lanesboro (Coffee Street) from the northeast approach span, view facing east. Parking area west of the bridge from the bridge approach, view facing southwest.

8 Verticals, diagonals, and struts. View facing northeast. Bridge portal and original bridge plate (repainted in 2002), view facing southwest.

9 Underside of bridge showing floorbeams, stringers, and pin connections, view facing northeast. Replacement railing and new wood decking, view facing west.

10 Original steel caissons and limestone abutment on the northeast end of the bridge, view facing northeast. Original limestone pier (now abutment) and bearing, view facing south. Note the addition of a concrete cap to the top of the limestone.

11 Non-historic utility pipe and pin connection, view facing east.

12 Historic Maps and Photographs Figure 1. Detail of Lanesboro found in the 1896 Standard Atlas of Fillmore County Minnesota. The Coffee Street Bridge is noted with a red circle (added). George A Ogle & Company, Standard Atlas of Fillmore County Minnesota (Chicago: George A Ogle & Company, 1896).

13 Figure 2. c.1895 aerial view of Lanesboro. Note the approach spans for the bridge. Image from the Lanesboro Museum photograph collection, Lanesboro, Minn.

14 Figure aerial of Lanesboro with Bridge 7965 at the center. Image from the Lanesboro Museum photograph collection, Lanesboro, Minn.

15 Figure photograph of Bridge 7965 facing northeast. Note the utility pipe to the left. Image from the Lanesboro Museum photograph collection, Lanesboro, Minnesota.

16 Figure photograph of the rehabilitation of Bridge 7965, view facing west. Image from the Lanesboro Museum photograph collection, Lanesboro, Minn.

17 Location map