The Nature Conservancy. Protecting nature. Preserving life.™

Groundwater provides a vital source of drinking water and creates critical habitat conditions for a broad range of species and ecosystems in the Pacific Northwest.

Human activities and increased pressure on groundwater systems, however, have the potential to alter the supply or quality of  groundwater, which, in turn, can affect how groundwater supports fish and wildlife.

At The Nature Conservancy, we’re working to better understand groundwater and biodiversity relationships, and develop effective approaches for protecting groundwater quantity and quality.


Across Oregon and Washington, we are identifying and mapping key locations where groundwater is important to conservation and evaluating types and locations of critical threats.

We are also developing analysis tools to assist resource managers in understanding the links between groundwater and biodiversity, and are testing strategies for groundwater management to protect and restore groundwater-dependent ecosystems and species.

We have completed a scientific assessment for Oregon, Groundwater-dependent Biodiversity and Associated Threats. Land and water managers are finding it an essential resource in the quest to reduce risks to groundwater-dependent ecosystems and protect groundwater quality and abundance. The assessment includes a main report, an atlas, and an appendix on methodology designed to enable the assessment tools to be used in other places.

Groundwater fast facts:

• Groundwater can be essential to six different types of ecosystems – rivers, springs, wetlands, caves, lakes, and deep-rooted plant communities (phreatophytes).
• In Oregon, groundwater provides 40% of drinking water; in rural areas, it’s over 90%.
• In parts of Oregon and Washington, groundwater pumping has lowered the water table by 100-300 feet in the past 40 years.