Manchester, New Hampshire
Stabilization and restoration of 200-ft of streambank. The design mimicked the appearance of a natural streambank but was developed to perform as a more traditionally stone armored bank. The project area is located upstream of a dam that was removed, leaving the channel to naturally wander through more than a century of deposited sediment. The channel moved approximately 50-ft in the two years following the dam removal and further movement would threaten adjacent sewer and gas lines.
Rather than traditional stone riprap, this design used two tiers of large sub-angular boulders to provide bank stability and protection. Vegetation was planted between the boulders to provide near-shore riparian cover, enhance aesthetics, and add erosion protection. Services include:
Site inspection and evaluation
Topographic survey
Hydrologic and hydraulic evaluations
Evaluation of alternatives
Preliminary and final design
Permitting
Construction cost estimating
Coordination with NHDES, US F&W, NH F&G, and local agencies
Construction observation