Bio-degradable Coir Log
Bio-degradable Coir Log is a suitable material to be used to stabilize the toe of a stream bank in order to re-grade a stream bank or completely reconstruct a stream bank. This material is made from coconut fibers that will prevent erosion, but will foster plant growth amongst the fibers and eventually bio-degrade becoming a natural part of the stream bank. The use of these logs is only appropriate in areas of low gradient (low elevation change within a stretch of stream) because high velocities will threaten to pull the logs from their entrenchments. Coir Logs should be trenched into the stream bank, weighted in the trench with large stone and then molded to the desired shape of the stream bank. In addition, wooden stakes should be pinned to the stream bottom and tied together with bio-degradable twine fastening the logs to the stream bottom at approximately 2-foot intervals down the length of the log. Bio-degradable Coir Logs will stabilize the toe of a stream bank, but stream banks should be graded to an approximate 3:1 grade (as you move horizontally 3 feet the bank should rise vertically approximately 1 foot). The stream bank should then be planted with native vegetation to ensure the long-term stability of the stream bank. The grade of the stream bank behind the coir logs allows the stream greater access to the floodplain. The root system created by the vegetation within the riparian buffer prevents future stream bank erosion due to high flows.
