500,000 people, one aquifer: Kootenai's only water supply faces challenges

The Spokane Valley-Rathdrum Prairie Aquifer, the water source for over 500,000 people in Idaho and Washington, faces mounting challenges from development, a drier climate and potential contamination.

The aquifer encompasses 370 square miles, the bulk of which lies beneath Kootenai County. From there, it flows underground into Washington where it discharges into the Little Spokane River, according to the Spokane Valley-Rathdrum Prairie Aquifer Atlas. It is the source of almost all drinking water for the Spokane and Coeur d’Alene regions, in addition to the water used for irrigation and industrial purposes. In Kootenai County alone, over 2,200 wells tap into the aquifer.

As water is pumped, the amount in the aquifer decreases each year before being recharged by snowmelt in the spring.

While demand on the aquifer can be predicted with some reliability, the amount of available water at any point in the future is harder to predict. That’s because the extent to which the aquifer recharges is almost entirely dependent on meteorological factors, Meg Wolf from the Idaho Water Resources Research Institute said.

“Drought impacts aquifer recharge by reducing annual and multi-annual precipitation contributions,” said Wolf. “Warm, dry conditions during drought increase evaporation and transpiration rates, sending more water back to the atmosphere and reducing water available during recharge.”

Currently, northern Idaho and eastern Washington are categorized as “abnormally dry” by the National Weather Service, meaning less precipitation is available to recharge the aquifer even as water continues to be drawn from it.

More development in the area taxes the resource even more and can lead to a greater risk of contamination through hazardous waste disposal, increased storm drainage, wastewater discharges, inadvertent spills and illegal dumping.

Development also increases winter road treatment on roads, called chlorides and fertilizers for lawns and landscaping, called nitrates.

Kootenai County Commissioner Leslie Duncan said the community must recognize the aquifer’s vulnerability to contamination.

“Contamination of the aquifer will devastate our community,” she said. “As our county continues to develop and grow, the risk of contamination or degradation to the aquifer increases. Education is key to newcomers on how development impacts the aquifer. We must commit ourselves to the aquifer’s protection to preserve our current quality of life, as well as the value of our individual properties.”

Locally, protection efforts have favored education over enforcement.

“There’s a balance between having people go onto your property or into your business and inspect for safe handling procedures versus having a very hands-off approach and addressing issues if there’s an incident afterward,” Commissioner Bruce Mattare said. “Where do you find that happy medium between the two?”

The county’s biggest area of influence is land use. Policies for land use are driven by the county’s comprehensive plan. Mattare said he’d also like to see the county work together with city leaders.

“It would be nice to have serious conversations about linking our comp plans so we can have a more comprehensive approach, not just to the growth of the community but looking at the aquifer and what we can do collaboratively to address the issues related to its quality,” he said. “Those are big ways where we can have impact.”

Protecting the aquifer from contamination can take many forms. Duncan said it’s up to the community to choose the methodology that best suits everyone.

“That said, if we do not establish protective areas and open space soon, regulation of land uses and education of the public on the aquifer’s vulnerability will be our only options for protection,” she said.

Last year, Kootenai County voters rejected a $50 million bond meant to curtail development on the Rathdrum Prairie. If the bond was approved, funds would’ve been used to acquire open space properties throughout the county and pay for recreational amenities. Properties purchased with bond funds would be available for public use and would not be sold or converted for other purposes.

After the election, commissioners speculated that the bond failed largely due to a lack of community outreach and education on how the bond could benefit the county, including by restricting development over the aquifer.

Though commissioners expressed an openness to bringing the bond to voters again in the future, if public interest is high enough, it won’t happen this year. Mattare said this is because including the bond would make general election ballots three pages long.

“Our machines cannot count three-page ballots,” he said.

If the county floats the bond again, Mattare said, it will be important for community members who are passionate about protecting open space to take up the cause.

“I’m really trying to organize people outside of government who want to champion this,” he said. “The government’s tax dollars can’t be used to advocate for or against an initiative. I think a neutral, bland approach would not be able to communicate the benefits effectively.”