Boulder Clusters
The boulders will each be at least 3.9 feet in diameter. Five boulder clusters will be installed. Each cluster will consist of three boulders arranged in a triangular pattern facing upstream. Within each cluster the boulders will be separated by a distance equal to the diameter of the boulders. For each cluster, the two downstream boulders will be placed in the periphery of the upstream boulder. The boulder clusters will be placed in the thalweg of riffles or runs
Flagstone Cover rocks
The flagstone structures will consist of a flagstone cover rock placed on top of two footer rocks. Two flagstone structures will be installed. The flagstone structures will be placed in the thalweg of runs and glides. The flagstone cover rock will weigh at least 3,800 pounds. The recommended dimensions of the cover rock are 4ft x 4ft x 1.5ft, but it is acceptable for the dimensions to vary as long as the minimum weight is met and the rock is somewhat wide and thin. The footer rocks will be sized to be about half the size of the cover rock (2ft x 2ft x 0.75ft). The footer rocks will be 50% embedded in the stream substrate and should have a somewhat flat top to best support the cover rock. The footer rocks will be oriented and filled with stream substrate to create a cavity beneath the cover rock that is 5-10 inches tall and 12-18 inches wide. The stream substrate will be filled in around the footer rocks to create one entrance to the nest cavity that is approximately 2-4 inches tall and 4-8 inches wide. The entrance will be directed at a 65 degree angle downstream of the structure.
Habitat placement
Our final design will consist of alternating placements of boulder clusters and flagstone cover rocks within our project reach in Little Stony Creek. Within the stream the structures will be placed 25-140 linear feet apart.