PDFWAC 173-527-100

Future appropriations for interruptible use.

(1) Ecology finds there may be water available above existing water rights and instream flows, which may be captured for interruptible use. This water is only available from November 16 to May 14 and may only be withdrawn from the Kalama, North Fork Lewis (below Merwin Dam), and East Fork Lewis rivers.
(2) Prior to commencement, the person or entity seeking a new interruptible appropriation must demonstrate a seasonal need and provide assurances that any effects on surface water that may result from withdrawals will be limited to the above time period and locations.
(3) Ecology shall deny an appropriation for interruptible use if such use, or the cumulative effects of such uses, would compromise habitat-forming functions provided by high flows. In no case shall new individual or cumulative allocations exceed the values indicated in Table IV as specified for each river. However, these allocation limits may be lowered on a case-by-case basis whenever more protection of habitat-forming functions is needed.
(4) Interruptible uses are subject to existing water rights and instream flows set in WAC 173-527-060.
Table IV
Limits on Future Allocation for Interruptible Uses
River Name
Allocation Limit*
(cubic feet per second)
Kalama River
150
Lewis River (from river mile 7.1 to Merwin Dam)
200
East Fork Lewis
90
*The allocation limits in this table are based upon an allowance for ten percent of the average historic flow. Due to case-by-case determinations of flow for habitat-forming function needs, the maximum allocation may be less.
[Statutory Authority: Chapters 90.82, 90.54, 90.22, 90.03, and 90.44 RCW. WSR 09-01-126 (Order 08-02), § 173-527-100, filed 12/19/08, effective 1/19/09.]