Water Quality Resources

Total Maximum Daily Load is the calculation of the maximum amount of a pollutant allowed to enter a waterbody so that the waterbody will meet and continue to meet water quality standards for that particular pollutant.

Water samples are collected to measure E. coli to make sure water is safe for public recreation, such as swimming, fishing or canoeing. E. coli is considered an indicator organism, used to identify fecal contamination in freshwater and indicate the possible presence of disease-causing bacteria and viruses.

Selenium is a naturally occurring element present in sedimentary rocks, shales, coal, and phosphate deposits and soils. There are around 40 known selenium-containing minerals but all are rare and generally occur together with sulfides of metals such as copper, zinc and lead.

Selenium can be released into water resources by natural sources via weathering and by anthropogenic sources, such as surface mining, coal-fired power plants, and irrigated agriculture.

Selenium bioaccumulates in the aquatic food chain and chronic exposure in fish and aquatic invertebrates can cause reproductive impairments (e.g., larval deformity or mortality). Selenium can also adversely affect juvenile growth and mortality.

Selenium is also toxic to water fowl and other birds that consume aquatic organisms containing excessive levels of selenium.

What we know: PFAS are widely used, long lasting chemicals, components of which break down very slowly over time. Because of their widespread use and their persistence in the environment, many PFAS are found in the blood of people and animals all over the world and are present at low levels in a variety of food products and in the environment.

PFAS are found in water, air, fish, and soil at locations across the nation and the globe.

Scientific studies have shown that exposure to some PFAS in the environment may be linked to harmful health effects in humans and animals.

What we do not fully understand: How to better and more efficiently detect and measure PFAS in our air, water, soil, and fish and wildlife, how much people are exposed to PFAS, how harmful PFAS are to people and the environment, how to remove PFAS from drinking water, and how to manage and dispose of PFAS