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January 21, 2020

Hoyle, Tanner Designs Two Vermont Bridge Replacements and a Unique Cattle Crossing

Hoyle, Tanner recently completed the design and construction inspection services for two culvert replacements, Bridge 5 and Bridge 6, located on East Road in Milton, Vermont. Our team was able to meet a fast-paced schedule completing the design, permitting, and Right-of-Way coordination in just 6-months from the contract award.

Located on a low dipping curve with sight distance issues, Bridge 5 had steep embankments and a drainage issue affecting the roadway cross slope, all contributing to a history of vehicle accidents at the site. To address this safety issue, Hoyle, Tanner provided a cost-effective solution to raise the road five feet at the curve low point, greatly improving sight distance while minimizing permanent impacts to neighboring properties.

Our team developed a 17’ clear-span precast concrete rigid frame and an innovative channel cross-section that included an armored bench, consisting of interlocked stone pavers (to be installed in spring 2020), for an erosion-resistant cattle crossing through the culvert outside of the stream channel. A cattle crossing was an essential feature of this structure, as neighboring property owners use it to access pastures on both sides of the road.

A 20’ clear-span precast concrete box culvert was designed for Bridge 6 with a removable top section to reduce precast piece weights and allow for ease of stream embedment material installation. Our team was able to save the Town money by accurately modeling existing and proposed conditions using 2D hydraulic analysis software to select an appropriately sized replacement structure. This cost-savings of more than $100,000 allowed the Town to complete the replacement of another smaller culvert in town.

Constructed simultaneously to aid in an accelerated schedule to reopen this vital connector route in Milton, a full road closure was implemented at both Bridge locations. Construction was completed in November 2019, meeting the Town’s goals for opening the road and avoiding conflict with future town construction projects.

 

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milton bridge winter photo