Changing Course: Revisiting Instream Flow Rulemaking in Washington State Following \u3ci\u3eSwinomish v. Ecology\u3c/i\u3e

Since the adoption of Washington’s Water Resources Act in 1971, legal recognition of instream water uses to preserve fish, wildlife, and other environmental values have become firmly entrenched in Washington water law. By establishing “instream flow rules,” rules that require a certain amount of water to be left in streams before water may be withdrawn for any new uses, the Washington State Department of Ecology (Ecology) must protect the environment while also managing water to achieve “maximum net benefits” for the people of Washington State. Ecology may only allow new withdrawals of water that will impair established instream flows if it finds that “overriding considerations of the public interest” will be served. In two recent cases, Swinomish Indian Tribal Community v. Washington State Department of Ecology and Foster v. Washington State Department of Ecology, the Washington State Supreme Court invalidated Ecology’s reliance on this statutory exception in authorizing water rights that will impair instream flows, instead, interpreting the language of the exception very narrowly. This Comment analyzes instream flow rulemaking in light of these cases, concluding that the decisions constrain Ecology’s ability to adapt existing rules to changing conditions, and that current law is therefore inadequate to address future challenges, including limited water availability and climate change. To better address these challenges, instream flow rules should be both more precise and more responsive to future conditions. To this end, Washington law should require instream flow rules to conform to a “best available science” standard tailored toward achieving healthy fish populations. In addition, investment in infrastructure for Washington’s existing Trust Water Rights Program to help expand water banking activities throughout the state, is needed to facilitate market transfers of water to supply unmet instream flows and new out-of-stream uses