WA Department of Ecology has authority to set instream flows. The term “instream” is used to identify a specific stream flow (typically measured in cubic feet per second, or cfs) at a specific location for a defined time, and typically following seasonal variations. Instream flows are usually defined as the stream flows needed to protect and preserve instream resources and values, such as fish, wildlife and recreation. Instream flows are most often described and established in a formal legal document, typically an adopted state rule.
The Yakama Nation (YN) has taken the position with WA Department of Ecology (October 11, 2012) that “as fishery co-manager, the YN naturally is anxious to see conditions in the mainstem and spawning tributaries conductive to supporting not only existing aquatic life and fish and wildlife populations, but also those expected to soon return.”
Elements of a watershed plan include: water quantity (required), water quality (optional), and habitat (optional), which can include instream flow.
Instream flows must be established in tributary streams to protect water quantity and quality and aquatic habitat. Instream flows must be sufficient to provide habitat, including spawning, for returning salmonids some of which are listed under Endangered Species Act. The proposed Husum/BZ Sub-Area Plan does not address yet to be determined instream flow requirements, which are also claimed by the Yakama Nation: “The YN has an unqualified Treaty fishing right and a Treaty water right in all streams flowing through its Ceded Area (which includes the White Salmon sub-basin) for flows adequate to support fish and other aquatic life; this is senior to all other water rights.”
See Watershed (WRIA 29b), Husum/BZ Sub-Area Plan, and Tribal Treaty Fishing Rights for additional discussions.