Twin-Pipe Structure Replacement
ODOT District 12-0, Hambden Township, Geauga County, OH |
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Bate’s Creek flows under State Route 166 in Hambden Township by way of two 6 ft. squashed pipe culverts that convey the meandering stream through wetlands, ponds and residential properties. The original structure, built in 1961, is considered a bridge by ODOT according to state law due to its combined 12 ft. overall span; therefore, the structure is inspected each year.
The project involved studying precast box culvert sizes to determine if the span could be reduced to below 10 ft. so that the District could remove it from the State’s bridge inventory. As part of the scope, Stahl Sheaffer performed hydraulic studies with several combinations of grade changes, stream geometry, culvert length, and precast box sizes, ultimately finding an optimized combination that conveyed the design-year storm with a 9’x4’ box while keeping velocities in check. Scour countermeasures were designed using conventional rock channel protection with ODOT RCP Type B along the inlet wingwalls and Type C at the outlet. |
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The project replaced a minimal amount of roadway and guardrail, removed sandbars, and mildly realigned the channel up and down stream to improve stream flow, and featured an MGS guardrail with socketed posts to keep the construction footprint narrow and the roadway ditches from needing to be realigned. These prudent measures helped the District avoid spending money on work that didn’t necessarily improve operations.
The project was environmentally approved under a Categorical Exclusion C2 document. Right of way takes included two channel easements and four temporary easements for construction. Tracings were approved in January 2020, and the project sold below the published engineer’s estimate in January 2021. This successful project was Stahl Sheaffer’s first with the Ohio Department of Transportation.
The project was environmentally approved under a Categorical Exclusion C2 document. Right of way takes included two channel easements and four temporary easements for construction. Tracings were approved in January 2020, and the project sold below the published engineer’s estimate in January 2021. This successful project was Stahl Sheaffer’s first with the Ohio Department of Transportation.
Existing Outlet
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Existing Inlet
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