Stream Restoration and Improvement
Stream restoration and improvement using river morphology techniques is the latest fad sweeping the environmental movement. We have no problem with certain techniques in use today to improve stream habitat, however, whether the method is Rosgen or someone else quantifiable results should be seen. It should be noted that before any stream work is done that the stream or river should be benchmarked.
Furthermore, realize that channel restoration or improvement is not a panacea. It will not solve all the environmental problems even if it succeeds in doing what it is designed to do. The latest reincarnation of these morphological techniques are based on the theory that you classify various streams and develop models to use to change the channels to support these classifications.
It must be said that many top not notch river geomorphologists do not support this theory. The quality of the work is often dependant on a number of conditions including the experience and understanding of the engineers as well as the original observations and plan.
We have noted two disturbing trends in some of the work done in stream improvement in the last few years that have resulted in declines in macroinvertebrate communities and diversity. These two trends are homogenization of current speed and substrate. Both of these will lead to a decline in biodiversity.
We also believe that these techniques often work better on some types of streams than others. Many of these models do not apply well to slow moving limestone spring creeks. We have a good handle on this so feel free to contact us on advice and benchmarking prior to actual changes in the stream. These firms are suppose to benchmark before they start but some are cutting costs. Furthermore, we can recommend some firms we have worked with and trust in these areas.