Coal Creek Bridge No. 3035A Replacement Project

Project overview

The old 64-year-old timber support structure was decaying, the 109-year-old steel floor beams were rusted, the paint was peeling, and the bridge had weight restrictions for heavy trucks. All traffic used a temporary bypass bridge throughout construction until spring 2023, when the new bridge opened.

Work to remove and replace the old Coal Creek Bridge on SE Lake Walker Road was originally planned for summer 2021, but was delayed one year to spring/summer 2022. The one-year delay was needed because crews are only permitted to do in-water work during late spring and summer. The new, replacement bridge, scheduled for completion in winter 2023, will carry no weight restrictions, and is expected to last for decades.

Construction timeline

• Pre-construction utility relocation: Summer 2021
• Construction of temporary bridge and traffic shift: Winter/early spring 2022
• Old bridge removed and new bridge built: Spring/summer 2022 through winter 2023
• Project complete: Winter 2023

Project budget

The bridge replacement cost was $4.7 million.

Bridge history

• Built in 1958 with timber creosote substructure
• Used recycled superstructure from a different bridge
• Is sole access bridge - serves single family and mobile homes
• Is two-lane single span bridge, 41 feet long and 18 feet wide
• Has 310 vehicles per day including about 5 trucks per day

Construction photos

Feb. 17, 2023 – One crew member stops traffic while others work on the curbs along the new bridge. Permanent guardrail and bridge railing were installed in early spring 2023. These replaced the concrete barriers and orange safety barrels along the bridge.



Feb. 7, 2023 – The new bridge stretches across Coal Creek into the Lake Walker community.



Feb. 7, 2023 – A stop sign gives drivers more time to see traffic coming over the new permanent bridge.



Dec. 14, 2022 – Our contractor crew took advantage of the dry weather before the next snow storm to begin the new bridge deck construction.



Oct. 18, 2022 – It took several crewmembers to set a massive girder for the new Coal Creek bridge.



Oct. 14, 2022 – A huge crane safely hoists a girder for the new bridge.



Sept. 16, 2022: Crews continue to make progress by adding supports to the new bridge.



Aug. 24, 2022: A crewmember forms rebars for the first abutment—what connects the road—to the new bridge.



Aug. 12, 2022: Crewmembers direct the pour of concrete for the new bridge.



June 30, 2022: The entire bridge is removed, an excavator is used to dig out the remaining creosote timber support beams. The large pipe down the center keeps the running stream safely away from construction activity.



June 30, 2022: With the bridge deck removed, crews use large metal claws attached to a boom to claw away the old, rusted metal side rails.



June 14, 2022: Crews finish routing the stream through a large metal pipe to keep fish and wildlife safe from construction activity. The old Coal Creek Bridge pictured here was completely removed on June 30, 2022.



June 10, 2022: A large truck transported 60-inch pipes for fish bypass over the temporary bridge.



June 10, 2022: A close-up look at two of the 60-inch pipes for fish bypass.



May 24, 2022: An old, worn-out culvert is replaced to help direct the flow of water through Coal Creek.



May 20, 2022: The wider approach to the temporary bridge (shown above) was added in May 2022. The wider approach helps larger vehicles like trailers and buses to cross more easily.



May 20, 2022: Stop signs at both sides of the temporary bridge help increase safety for travelers coming to and from the Lake Walker community.



March 29, 2022: Travelers will now use the single-lane temporary bridge (left side of photo). Crews removed the existing bridge (right side of photo). We can only do work over and in the creek during the warmer months when there is less impact to fish.



March 18, 2022: Crews add the finishing touches to the new, temporary bridge (right side of photo). The existing Coal Creek bridge (left side of photo) was closed to traffic after traffic was shifted onto the temporary bridge.



March 10, 2022: Crews worked to install the bridge deck on the temporary Coal Creek Bridge. This temporary bridge was in place throughout construction of the new, replacement bridge.



March 10, 2022: A tractor smooths out the top of the approach ramp crews use to access the bridge decking that was under construction on the temporary Coal Creek Bridge.



Coal Creek Bridge No. 3035A located southeast of Black Diamond in unincorporated King County.

 

Why did King County is replace this bridge

Sections of steel were being lost.

The super-structure was 109 years old and severely rusting.

The 64-year-old creosote timbers were rotting.

Paint was peeling.