Dead Cambridge River Fish Barrier
Upton, ME
SA conceived of and designed a cost-effective fish barrier to protect the prime native brook trout habitat upstream from invasive species.
The Maine Department of Inland Fisheries and Wildlife, the Rapid River Coalition, and Trout Unlimited were significantly concerned about migration of smallmouth bass, illegally planted into Lake Umbagog in the 1980s, into the native brook trout waters of the Dead Cambridge River and C-Pond and wanted to design a dam to prevent upstream movement of these invasive species.
SA volunteered its services, pro bono, to assist local conservation efforts in restricting the passage of invasive species into this prime native brook trout habitat.
Rather than designing and constructing a dam with an unnecessary impoundment, SA conceived of blocking fish passage by cutting a waterfall in the rock as a fish barrier. This innovative approach was more cost effective, simpler to construct, eliminated potential risks of dam failure, simplified permitting, and achieved the goal of blocking unwanted fish passage compared to the complexity, cost and risk associated with a dam.
SA surveyed river and bank topography, performed subsurface explorations to evaluate rock characteristics, and designed the rock cut, including dowels to reinforce the rock face and adjacent river banks. During construction, SA observed the work and consulted with the Maine Department of Inland Fisheries and Wildlife and worked with the contractor to adjust design as the rock was uncovered and blasted. After rock quality was found to vary significantly, SA designed a timber crib and deck to maintain the barrier.