Sucker Brook

Sucker Brook is a stream that presented a unique challenge for Piscataquis County. The roadway profile was tight, soil cover was limited, and the crossing needed to improve passage for aquatic organisms without expanding the construction footprint. The solution had to fit the site, not force the site to fit the structure.

THE CHALLENGE: Limited Cover and Constrained Geometry

The site offered limited roadway cover and a constrained road profile, limiting the depth available for traditional culverts or large arch systems. Pipe and box culverts were evaluated, but could not provide the required span or meet the aquatic organism passage goals identified by the project owners within the site’s constraints.

A four-sided box culvert would have required substantial in-stream work and labor-intensive efforts to recreate a natural streambed within the structure. A clamshell culvert was also considered, but procurement lead times exceeded the project schedule, and installation would have required greater excavation than the site could reasonably accommodate.

Each alternative was reviewed in the context of constructibility, environmental impact, and long-term performance.

THE SOLUTION: Gravity Abutments and an Open-Bottom Configuration

Velpont gravity abutments were selected because they addressed both structural and environmental requirements within the available footprint. Velpont’s modular precast system simplified foundation work and reduced uncertainty in a rural setting.

The open-bottom bridge design preserved the natural streambed and supported long-term stream continuity. Velpont abutments paired cleanly with Dirigo Bridge Company’s 15 ft (4.5 m) box top, delivering a durable structure with a predictable construction sequence and clean appearance.

THE PROJECT: Prefabricated Components and Field Adjustments

Installation focused on prefabricated elements rather than on in-place construction. Precast abutments and the box top were delivered and set with common equipment, maintaining consistent geometry and alignment while limiting in-stream disturbance.

This type of crossing can typically be installed in about a week; however, an additional 1-2 weeks were needed to correct alignment errors unrelated to the Velpont system itself.

Despite the delay, the streamlined sequencing minimized the duration of work within the channel and reduced impacts to the surrounding stream environment. The site was stabilized and restored promptly following installation.

THE OUTCOME: A Resilient Crossing for the Long Term

The completed crossing delivers improved hydraulic performance, restored aquatic connectivity, and more dependable roadway passage. By preserving the natural streambed and eliminating a fully enclosed structure, the project reduced future maintenance concerns and improved long-term resiliency.