Groundwater Program

Mission Statement

“High quality groundwater on the Nez Perce Reservation provides nearly 100% of the potable water supplies for the Nez Perce people. The Lapwai Valley Aquifer is a portion of the federally designated Lewiston Sole Source Aquifer and scientific studies have documented that streams and groundwater are hydrologically connected. Our mission is to protect high quality groundwater from degradation and to restore contaminated groundwater to beneficial use.”

Hydrogeologic Background

Geologically, the aquifers are contained within stratified basalts of the Columbia River Basalt Group that have been subsequently folded and faulted. Aquifers occur between the basalt flows and are localized primarily along permeable basalt flowtops. The interiors of the flows consist of massive basalt with relatively little water passing vertically between the basalt flows. This results in a stratification of aquifers that typically function independently of each other. The best example of this vertical separation of aquifers is based on an administrative declaration of a Ground Water Management Area for the Lindsey Creek Aquifer, which is producing its water from the Saddle Mountain and Wanapum Basalts formation.

Goals

Pollution prevention is the most effective method of protecting valuable high quality groundwater resource through implementation of regulatory standards and best management practices to be applied to all activities by the NPT Tribe, industry, agriculture, municipalities, private homeowners, and public transportation corridors within the Clearwater River Watershed.

Science-based soil and groundwater assessments and environmental cleanups will strive to remove  contamination where feasible and minimize damages to human health and the environment

Establishing groundwater monitoring points for both water quality and quantity (e.g. water level)  will provide a long term record that will be useful to the Tribe in trend analysis and potentially useful as a predictive tool useful to land managers

PFAS

Although they’ve been in technology we use everyday since the 1940’s, forever chemicals that are extremely resistant to degradation in the environment, have just been making headlines in the last few years. Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals. PFAS have been manufactured and used in a variety of industries around the globe, including in the United States since the 1940s.