Technical Description:
• CON/SPAN
® O-Series
® Bridge System
• Span: 28'
• Rise: 7'-7"
• Length: 32’
In order to improve fish passage and flood resiliency, the United States Forest Service (USFS) completed 255 stream crossing projects across the country in fiscal year 2018. Conventionally designed stream crossings, particularly if they are undersized, can affect water quality and also clog and fail during flood events.
In the Monongahela National Forest in West Virginia, an existing corrugated metal pipe arch was undersized and perched 2' above the water surface. Since it restricted fish passage and natural stream processes while also showing signs of deterioration, the USFS decided it needed to be replaced. A 28' x 7'-7" CON/SPAN® O-Series® Bridge System, 32' in length, from Contech Engineered Solutions was selected as the best replacement solution.
According to Abigail McQueen, Stream Restoration Specialist with Trout Unlimited, a CON/SPAN was selected for a number of reasons. "From a fisheries standpoint, the concrete arch with EXPRESS® Foundations provided us the ability to easily construct a natural stream bed and banks between the foundation blocks, allowing for efficient water and sediment transport and fish passage through the structure at all flows. From a maintenance and constructability standpoint, the structure was selected because of its longevity, low maintenance, and ease of installation at such a remote location."
Trout Unlimited, a national non-profit organization "dedicated to conserving, protecting and restoring North America’s coldwater fisheries and their watersheds," partnered with the USFS on this project and provided part of the funding.
The installation went smoothly with McQueen noting that "Contech staff provided valuable assistance in the field, and the truck drivers were able to maneuver under tight working conditions on a remote, single-lane gravel road for a smooth installation with all arch units being offloaded and set in a matter of hours."
"Trout Unlimited commends the Forest Service for its leadership on reconnecting vital habitat in order to sustain our coldwater fisheries," concluded Chris Wood, President and CEO of Trout Unlimited.
Technical Description:
• CON/SPAN
® O-Series
® Bridge System
• Span: 28'
• Rise: 7'-7"
• Length: 32’