In Idaho, there are a few regulatory agencies that have control over water quality.
Idaho Department of Environmental Quality (IDEQ) – This is the primary agency that regulates water quality in Idaho. (They do air quality and wastewater too.) This agency sets guidelines for water quality, plus they map water sources and potential contamination.
IDEQ does not regulate water quality for domestic wells. However, most lenders require that the water is proven to be potable (safe to drink) before the sale can go through.
It can be prohibitively expensive (thousands of dollars) to “test for everything.” We typically identify likely contaminants in order to keep testing fees reasonable.
South Central Public Health District (SCPHD) – Where IDEQ is more concerned with the natural environment, SCPHD is more concerned with the health of the people living in this area.
SCHPD has records for septic tank and water line installations. It’s a good place to look if you need to find out where the septic tank is on your property. They also have helpful links on water and air quality, and how to take care of your well and water system.
Environmental Protection Agency (EPA) – This is the Federal regulatory agency that sets nationwide standards for water quality.
Idaho has an agreement with the EPA that our DEQ offices manage water quality. The trade-off is that the DEQ standards have to be at least as strong as the EPA’s standards.
Idaho Department of Water Resources (IDWR) – IDWR is an Idaho agency that governs water usage – who gets to use it, and how much they’re allowed to use.
They also set standards for well construction. This is especially important, because a well that doesn’t have a good surface seal is like a soda straw that can suck contaminants down into the groundwater.
Another issue IDWR tracks is water rights. Basically, a water right is the legal right to use a certain amount of water for a certain application. If you want to, say, irrigate a corn crop, you’ll need to apply to get a water right for the amount of water you want to use.
In Idaho, a domestic well automatically comes with a domestic water right. This allows you to irrigate 1/2 acre of land with up to 13,000 gallons of water per day. If you’re using water for anything else, it’s only 2,500 gallons per day.
If you’re concerned, you can apply for an adjudicated water right. This grants you a water right with a specified date.
Water rights are adjudicated by seniority. If there’s not enough water in the local dams and reservoirs, then water is delivered to the people who hold the oldest water rights.