State of Our Watersheds: Well withdrawals should be capped

The state should propose a 350 gallon per day cap on permit-exempt wells withdrawing from the Stillaguamish watershed to protect against unaccounted over-withdrawal of water. By reducing the amount of surface water, over-withdrawal can harm salmon at all stages of their life cycle.

From the State of Our Watersheds Report, released last year from the NWIFC:

In the 2014 Stillaguamish Water Reservations Report, Washington Department of Ecology reported that 818 wells were withdrawing 143,500 gallons of water per day from the groundwater reserve for permit-exempt wells that was established in 2005. According to Ecology, an additional 50 to 75 exempt wells are drawing from the reserve every year. Accounting for the reserve is done for three sub-basins: the mainstem Stillaguamish, the North Fork Stillaguamish and the South Fork Stillaguamish.

This does not account for groundwater impacts to tributaries smaller than the mainstem, the North Fork, and the South Fork sub-basins of the Stillaguamish River.

In 1999, five separate small tributaries within those larger Stillaguamish sub-basins were found to be over-consuming groundwater, at a rate of 5% or more of groundwater recharge per year.

The amount of 143,500 gallons per day being drawn from the 818 wells is a conservative estimate of groundwater withdrawal, based on 350 gallons per day for wells with no associated septic and 175 gallons per day for wells with an associated septic. While that may approximate current use from the 818 wells, it must be pointed out that each permit-exempt well can legally withdraw as much as 5,000 gallons per day, so while current usage is estimated at 143,500 gallons per day, through the permit-exempt well program, 4,090,000 gallons per day are actually available to the 818 wells.

Learn more about the 2016 State of Our Watersheds report.