The Stark Street Bridge is a 277-ft steel truss bridge spanning the Sandy River two miles east of Troutdale, Oregon. The bridge connects Southeast Sandy Street with the Historic Columbia River Highway and is one of only two western entrances to the highway. Karl Billner designed the bridge, supervised by State Bridge Engineer Charles H. Purcell. Samuel C. Lancaster provided overall supervision during construction.
The bridge is located two miles from Troutdale, Oregon, over Sandy River, near the Portland Automobile Club House. This bridge replaces an old wooden structure which fell on Good Roads' Day, April 25, 1914, dropping a 5-ton auto truck into the river. The bridge consists of one 200-foot riveted, through, Pratt, camel back steel span, and one 77-foot Warren pony, riveted steel span, with reinforced concrete slab floor, and creosoted wood block pavement. Clearance above low water, 35 feet. Bitumen-filled expansion joints are provided in concrete slab over each floor beam. Clear roadway, 20 feet. Live load, four 20-ton trucks in line, with two 20-ton trucks passing. River pier, 36 feet high above base, of the diamond shaft, solid web type, of reinforced concrete...Price of bridge, completed, $21,042.40. George H. Griffin, contractor.
Multnomah County, Oregon, constructed the Sandy River Bridge (Stark Street Bridge) to replace an old wooden Pratt through truss. The old bridge had collapsed, coincidentally on Good Roads Day, April 25, 1914, dropping a five-ton truck into the river. It had served as part of the county's extensive rural road system. The river crossing was at the east end of Base Line Road, Which dated from 1854 when 30 people petitioned for a road to be built from the Sandy River to Portland "following the baseline as closely as possible". Base Line Road followed the surveyor's baseline between Township 1 North and Township 1 south, of Range 3 East, Willamette Meridian. It became one of three routes leading from rural eastern Multnomah County to Portland.
The portion of the Sandy River near Base Line Road was popular with the Portland Automobile Club, and between 1912 and 1913 the organization constructed a frame and stone building west of the bridge for picnics and other club activities. Sometime in the 20th century Base Line Road became an extension of Stark Street and so took on this name. In 1915, shortly after completion of the Sandy River Bridge (Stark Street Bridge), a new alignment for Base Line Road carried it down a long, gradual grade past the Troutdale Road, following the river to the Portland Auto Club camp. This new route bypassed a circuitous portion of the county road system with a route consisting of tangents, and gradual curves and grades carrying it down to the reverts edge at the bridge crossing.8
DESIGN AND DESCRIPTION
Construction began on the Sandy River Bridge (Stark Street Bridge) shortly after its predecessor collapsed. Though owned by Multnomah County, the bridge was constructed under the direction of the Oregon State Highway Department and bridge engineer Charles H. Purcell. It was constructed of one 10-panel 200'-21/2" riveted Pratt camel-back through truss steel span and one a-panel 77'-6" Warren pony truss, to a total length of 277'-81/2. Originally the spans had 20'-0"-wide reinforced-concrete decks with creosoted wood block pavement. Clearance above low water was about 35'. Total length of U6L6 (centermost vertical) on the main span is 32'-6". Total height of the Pony span at the middle of the third panel is 12'-0".9 A logical reason for choosing two unequal spans over one longer span for this location was that piers from the original wooden truss were reused with some modification. In addition, the main Pratt truss appears to be of a standardized design and length. Notations on original plans suggest that the specifications for both spans came from the American Bridge Company.10
A new river pier crib was sunk around the old pier with some difficulty as crews encountered boulders during their excavation. Nevertheless, they found a good layer of fine sand and loose gravel 20' below the stream bed and through this drove 31 piles with a 2,000 pound hammer. The bottom of the crib was sealed with 2' of concrete poured through a tremie pipe and hopper. The stream pier took the shape of two batter diamond-shaped legs connected by a continuous web wall. The shore abutments for the main span and the shore abutment for the Pony truss consisted of reinforced-concrete counterfeited piers with batter diamond legs and continuous webs. They were founded on loose rock and sandstone.11
Both spans were constructed entirely of riveted rolled channel, angle steel, I-beams, and lacing, with fixed ends on the main channel pier and expansion roller shoes on the abutment piers. There were 155.10 tons of steel used in the trusses and floor system and 218.4 tons of concrete in the piers; and 930 lineal feet of piling.12
The state highway department prided itself on its ability to supervise construction of high-quality, low-cost bridges for county roads during 1914. It accomplished this by designing spans and advertising for construction bids in standard engineering periodicals and local newspapers. This procedure differed greatly from the way in which county governments had previously proceeded, where there was no competitive bid process among bridge building companies for contracts. One individual associated with the highway department, most likely state highway engineer Henry L. Bowlby or bridge engineer Charles H. Purcell, wrote that county courts seldom had access to a competent bridge engineer to review their bridge construction proposals. Moreover, many relied completely on private bridge companies both for design and construction. "Bridge Companies (sic) employ the smoothest talker for their salesman that can be secured,' wrote the highway department official. He added, this is part of the selling end of the business, and does not differ from the selling end of any other commercial business." Also, "a County Court without the services of a competent bridge engineer is helpless in the hands of the average bridge company."
One of many cost comparisons cited in the First annual Report of the State Highway Engineer looked at the price advantage of the Sandy River Bridge (Stark Street Bridge) over a similar structure built by Lane County, on the south end of the Willamette Valley. While the cost-per-ton for steel for the Sandy River Bridge was $65.00, the cost-per-ton for steel for the Lane County structure was $184.72. The real difference in construction was that the Sandy River span was competitively bid, while the Lane County span was designed and built by one company, with minimal supervision by the county court. The Sandy River Bridge (Stark Street Bridge) cost $21,042.40.13
REPAIR AND MAINTENANCE
The Oregon State Highway Department designed and supervised construction of all bridges on the Multnomah County portion of the Historic Columbia River Highway except for the Sandy River Bridge at Troutdale (HAER No. OR-36-A). Except for the Sandy River Bridge (Stark Street Bridge), all of them became part of the state highway system in 1930 and were placed under the Oregon State Highway Departmental jurisdiction. Nevertheless, Multnomah County continues to own and maintain the Sandy River Bridge (Stark Street Bridge), primarily because it lies on Stark Street, a county road, at its junction with the HCRH, a state owned route .14
Because of increased traffic demands, Base Line Road's western approach to the Sandy River Bridge (Stark Street Bridge) Was widened in the mid-1930s. About the same time, probably as part of the road improvement project, rubble guardwalls at the eastern end of the bridge were replaced with a set that created a wider approach to the structures. The original guard walls on the bridge's east end were of the standard design used throughout the Historic Columbia River Highway, namely, random rubbleslipjoint masonry with arched drainage openings and a screened concrete cap. In their place, the 1930s construction included ashlar basalt fences that take on the appearance of a standardized U.S. Bureau of Public Roads plan or a National Park Service plan for masonry guard rails 15
Maintenance records for the Sandy River Bridge (Stark Street Bridge) through the 1960s are unavailable or lost. Those from the 1970s through the early 1990s reveal that after over sixty years or service, the bridge was showing the usual signs of aging for metal truss structures. In 1974, inspectors noted damage from oversized trucks. On the Pratt truss, angle steel on the east portal's lower edge was twisted out of shape and top chord struts were bent such that vertical columns were pulled in. In addition, sway bracing was badly damaged. By the mid-1980s, comprehensive inspections by the Oregon State Highway Division bridge engineers also found spalling on the main span under deck, and exposed reinforcing bar there and in the pier. Seats and bearings were covered with debris and the bearings in the west abutment were frozen. Paint was thin paint and there was minor section loss in floor beam flanges. Finally, the entire truss structure showed evidence of repeated encounters with oversized vehicles.16
In 1988, Multnomah County contracted with Davld L. Holt Company of snobbish, Washington, to flame-straighten much of the Pratt trusses superstructure. That same year an in-house inspection revealed that much of the reinforce-concrete decals surface had degraded. By the early 1990s, the bridge received a comprehensive upgrade with new steel channel and plate added to the present superstructure. The county also strengthened one lower chord with a Dywidag rod so it could bear sidewalk loads. Finally, the concrete deck was sandblasted and given an epoxy overlay.17