Is dredging of river channels an effective way to diminish flood damage?
In most cases dredging a river channel is not a practical solution. In most cases it must be done regularly over relatively long stretches of a river to significantly reduce the flood level in a river. Most rivers in Western Washington move large volumes of sand, gravel and other sediments. It is quite possible for a river to refill most or all of a dredged channel during the next significant flood. The cost of periodic dredging and disposal of dredged material often make dredging prohibitively expensive. The economics of dredging are much improved if a buyer, such as a concrete producer, can be found for the dredged material.
