Toward a Unified Reasonable Use Approach to Water Drainage in Washington

Competition for scarce water resources has been the predominant concern in Washington water law, but this Comment focuses on the opposite problem—the disposal of unwanted water. Water drainage has great significance as a problem which permeates land development. Almost any development of land is likely to alter the flow of water draining from the land to the possible harm of neighboring property. While many aspects of drainage are now regulated through institutional bodies created by the state legislature and municipalities, this Comment addresses the problems that arise between neighboring landowners when one alters the drainage of water to the consequent injury of the other.

This Comment considers the common law in Washington governing water drainage. In particular it analyzes the disparity between the standards of liability for diversion of diffuse surface and watercourse drainage. This Comment advocates a unified approach toward these two areas of water drainage by suggesting a balancing test of reasonableness for interference with water drainage.