An NPR member station
Play Live Radio
Next Up:
0:00 0:00
Available On Air Stations

North Idaho volunteer group works to keep Lake Pend Oreille healthy

A photograph of Boyer Slough, a tributary of the Pend Oreille River.
Boyer Slough, a tributary of the Pend Oreille River, surpasses the State Department of Environmental Quality’s recommended levels of phosphorus, said Jennifer Ekstrom, the North Idaho lakes conservation associate at the Idaho Conservation League. (Courtesy of Jennifer Ekstrom)

North Idaho lakes are a haven for water sports, but at least one volunteer group is working to remind the public that its local lake is not immune to water quality concerns.

The Idaho Conservation League, a statewide environmental protection nonprofit, works with a group of 30 volunteers to visit 15 locations across Lake Pend Oreille to sample and test its water quality.

Known as the Water Quality Monitoring Program, the program runs for five months between May and September, according to a blog post from the league.

The volunteers play an important role in the conservation league’s North Idaho Lakes Advocacyprogram, which focuses on protecting lakes in the Idaho panhandle from degradation, pollution and poor land use management.

The conservation league began the program in 2022 after the Lake Pend Oreille Waterkeeper — an independent water quality monitor group that worked in the area since 2009 — closed its doors after its director retired.

After taking over water quality monitoring in the region, the conservation league inherited 10 years of data from the previous group, and now partners with the Idaho Department of Environmental Quality to send in new data.

“It gives a feeling of hope, to be out there with so many others doing something proactive to protect the lake,” volunteer Deborah Crain said on the league’s website.

Jennifer Ekstrom, the North Idaho lakes conservation associate at the conservation league, said volunteers come from a variety of professional backgrounds, but they each share the same goal to protect Lake Pend Oreille.

Located in the North Idaho Panhandle, Lake Pend Oreille is the largest lake in Idaho. Like the Coeur d’Alene Lake, it is a popular spot for tourism and recreation.

Lake Pend Oreille does not have the same historic mining pollution issues as its neighbor, Lake Coeur d’Alene, but rather the lake’s issues come from population growth straining “outdated and overburdened” infrastructure, Ekstrom said.

According to the U.S. Census Bureau, Bonner County grew from nearly 41,000 residents in 2010 to an estimated 51,400 residents in 2022.

“Our primary concern is the number of people coming in and the way that our area is being developed,” she said. “Every person, whether you’re a local resident or a tourist, you have the potential to impact water quality in a negative way.”

One of the most problematic pollutants in Idaho waterways is phosphorus, Ekstrom said, because it produces invasive weeds and toxic algae that can harm fish and limit recreational activities.

Phosphorus enters lakes through a variety of ways including:

  • Local sewage systems that have permits to discharge into the water ways
  • Septic systems that serve individual homes or communities
  • Soil disturbance during the construction of a new home and stormwater carries it into the lake
  • Fertilizer runoff 

“Even if you don’t live on the shoreline or make a new development on the shoreline, our storm drains still carry that water into the lake,” Ekstrom said. “So even people who are fertilizing their lawns in the town – that still makes its way into the lake.”
There are certain areas of Lake Pend Oreille that Ekstrom said are “extremely problematic.”

Boyer Slough, a tributary of the Pend Oreille River, surpasses the State Department of Environmental Quality’s recommended levels of phosphorus, she said.

Ekstrom said sewer discharge into Boyer Slough is a significant contributor to those high phosphorus levels, and the development of new subdivisions and businesses is straining outdated sewage systems even further.

Despite water quality concerns, Ekstrom said she is hopeful that things will improve after seeing the commitment from community members involved in the monitoring program.

“We have the most dedicated volunteers,” Ekstrom said. “Many of them have been doing this for several seasons — even up to 10 years for some of them — and they are committed to get out on the water every month because they want to see our lake stay awesome.”

Tips to promote water quality, according to the Idaho Conservation League:

  • Avoid disturbing the soil near the shoreline. In Bonner County, there is a minimum 40-foot setback required where buildings are not allowed and retaining native vegetation is recommended. 
  • Don’t over-fertilize your lawn and garden. If you use fertilizer, choose a phosphorus-free variety. Phosphorus is fuel for algae and aquatic weeds and can make them grow out of control – making lake water unsafe. 
  • Keep leaves and other yard debris away from the shoreline and storm drains.
  • Don’t let oils, chemicals, dirt, and other pollution spill into the water or storm drains.
  • Observe No Wake Zones. Be aware that waves from boats can agitate sediment on the shoreline, pulling phosphorus into the water.
  • Divert stormwater so the ground soaks it up before it runs into the lake. 
  • If you have a septic system, make sure it is operating correctly. Panhandle Health District recommends having systems inspected every three years.

This story was originally published by Idaho Capital Sun