Ground Water

What Is Ground Water?

Ground water is water found beneath the Earth's surface that supplies wells and springs. Ground water is present in aquifers, which are underground soil or rock through which ground water can easily move. Aquifers typically consist of gravel, sand, sandstone, or fractured rock such as limestone.

Groundwater replenishes streams, rivers, and wetlands, providing about half of the flow to streams. It also provides fresh water for irrigation, industry, and communities. For 50% of all Americans (including 95% of the rural population), ground water is the primary source of drinking water. Within Region 8, about 78% of the the Public Water Systems rely on ground water and over 2.5 million people in Region 8 are served drinking water from ground water sources. Approximately 1 million rural residents within Region 8 rely on ground water from springs and wells for their household needs. Ground water is also a source of water used for irrigation in Region 8, supporting millions of dollars worth of food production.

What Is The Problem?

Rapid population growth in the western US over the past ten years has resulted in increased pressure to develop ground-water resources to satisfy water supply demands. At the same time, much of the West has experienced drought conditions, which has resulted in reduced ground-water recharge and reduced base flow to streams. Within Region 8, ground water is susceptible to contamination primarily from septic tanks, agriculture (pesticides, fertilizer and feedlots), mining, underground storage tanks, waste storage, treament, and disposal (landfills, hazardous waste), and urban and suburban sources. Once contaminated, ground water is very difficult and expensive to clean up.

Ground Water Protection

The Ground Water/Source Water Team in Region 8 strives to strengthen State, Tribal, local and EPA ground-water protection efforts. Our goal is to develop and implement ground-water management strategies that recognize long-term drought conditions in the Western US and increased use of and reliance on ground-water. We are working with local and state ground water managers to encourage integration of ground water and surface-water management in a way that recognizes they are a single resource. We work toward effective integration of ground-water protection, development and clean-up programs.

Local authorities are one of the primary means for protecting ground water. We help communities understand the need to protect their ground water and to provide scientific information to support the development of local protection measures. The EPA assisted in the USGS study of the Turkey Creek watershed in Jefferson County. The study focused on the contemporary (2001) hydrologic conditions and provided a hydrologic assessment of water resources in the Turkey Creek watershed. Hydrologic conditions are described on the basis of evapotranspiration, surface water, ground water, and water quality.

Nationally, EPA also sets and enforces drinking water standards, offers guidance to private well users, regulates the storage, transportation, treatment, and disposal of solid and hazardous wastes which may infiltrate groundwater systems and offers resources and expertise to facilitate the rehabilitation of contaminated ground water sources. Septic systems, private sewage systems, or individual sewage systems are an issue of national concern, prompting the U.S. Environmental Protection Agency to recently update sewage system guidelines. These guidelines can be found at Onsite and Decentralized Wastewater Treatment Systems Program.

ground water flow chart

Ground Water Information Links

EPA Links

Region 8 Environmental Education

Region 8 Source Water Assesment and Protection Program

EPA Office of Ground Water and Drinking Water

EPA Ground Water and Drinking Water Links to Partners

EPA Surf Your Watershed

Region 8 Ground Water Contacts

Darcy Campbell 1595 Wynkoop Street Denver, CO 80202-1129 (303) 312-6709 E-mail campbell.darcy@epa.gov	Gregory Oberley 1595 Wynkoop Street Denver, CO 80202-1129 (303) 312-7043 E-mail oberley.gregory@epa.gov
Carol Russell 1595 Wynkoop Street Denver, CO 80202-1129 (303) 312-6310 E-mail russell.carol@epa.govv	Mike Wireman 1595 Wynkoop Street Denver, CO 80202-1129 (303) 312-6719 E-mail wireman.mike@epa.gov