State of our Watersheds: Unpermitted wells imperil Nisqually River

Despite rough economic times and slow growth, the number of new unpermitted wells in the Nisqually watershed grew at a steady rate. That is a finding in the recently released State of Our Watersheds Report by the treaty tribes in western Washington.

From the report:

Between the upper and lower extents (of the watershed) is a focus area of 230 square miles with mostly flat to gently sloping land, three urban areas (Eatonville, Roy and Yelm) and 87% of the watershed’s water wells. This middle focus area of the watershed has seen the majority of water well growth in the past and in the last four years saw an increase of 85%. This area controls some of the most important and productive freshwater stream reaches for salmon in the Nisqually watershed. Unchecked growth and its associated increase in groundwater demand will reduce aquifer volume and thus the outflow to the streams, wetlands, lakes and saltwater nearshore vital to salmon.

The impact on salmon using these once productive freshwater streams will only increase as well drilling and growth continues:

Unmanaged population growth within the Nisqually watershed will have an increase demand on groundwater resources. Surface and groundwater withdrawals in WRIA 11 tributaries for irrigation and domestic use will continue to grow and will impact instream flows during adult salmon upstream migration and spawning. Unmanaged growth in the middle extent of the watershed may also lead to a decrease in summer flows thus reducing rearing area for fish residing year-round in the watershed.

More so-called exempt wells are drilled each year, but because they are untracked an unpermitted, hardly anything is known about their total impact on salmon and treaty rights.

Again, from the report:

Washington state instream flow rules allocate river flow for ecological requirements, but state law allows new wells to withdraw 5,000 gallons of groundwater per day without obtaining a permit that would require scientific evidence that water is legally available. Groundwater withdrawals can cumulatively affect streamflows, especially in late summer when flows are naturally low.

An aquifer’s natural outflow discharges into lakes, wetlands, streams and seawater through springs and seeps on the land surface and through groundwater. Adequate natural outflow is essential for sustaining base streamflows, maintaining lake levels, providing freshwater inputs to the nearshore, and preventing seawater intrusion.