The Nature
Conservancy
in Oregon is implementing a
comprehensive program to better
understand the links between
groundwater resources and
biodiversity, and to develop and
test actions that help ensure
conservation of groundwaterdependent ecosystems and
species.
Pacific Northwest
Groundwater and Biodiversity
We are working across the
region and at priority conservation
sites to develop tools and
provide information that
supports effective groundwater
management.
Fast Facts
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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 the drinking
water; in rural areas, it’s over
90% of the drinking water.
In parts of Oregon and
Washington, groundwater
pumping has lowered the water
table by 100-300 feet in the past
40 years.
Picture at top:
A spring on the canyon wall of the Lower
Crooked River, outside of Terrebonne,
OR. The river is groundwater-dependent,
due to the abundance of such springs.
Groundwater
© Marshall Gannett
Groundwater provides a vital source of water and creates critical habitat
conditions for a broad range of species and ecosystems in the Pacific Northwest. Groundwater input into rivers creates refuges of cool water that can be
critical during hot summer seasons. Some ecosystems, such as fens or
springs, receive no other water except groundwater. Good water quality,
essential to the survival of spring mollusks and other aquatic species, can be
provided by groundwater.
The pressure from humans on groundwater is expected to increase as
communities are turning more and more to groundwater to meet their needs.
Human activities have the potential to alter the supply or quality of
groundwater, which, in turn, can affect how groundwater supports
biodiversity. Excessive groundwater pumping can reduce cool water
discharge into streams or lakes and pesticides and fertilizers have the
potential to contaminate groundwater supplies.
Despite the importance of groundwater to biodiversity, the precise
relationships remain unclear. At The Nature Conservancy, we’re working to
improve this understanding and develop effective approaches for protecting
groundwater for biodiversity conservation.
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The Nature Conservancy, 821 SE 14th Avenue, Portland, OR 97214
Phone: 503 802-8100 Fax: 503 802-8199 E-mail: [email protected] Web: nature.org/oregon
Conservation in action
The Nature Conservancy is implementing a multi-tiered approach to protect
groundwater for biodiversity conservation. Across Oregon and Washington,
we have identified and map key locations where groundwater is important
to biodiversity conservation and evaluated and mapped the types and locations of critical threats. As part of this effort, we continue to document
methods and approaches for completing regional assessments to identify
groundwater focus areas and critical threats. In Oregon, in conjunction with
the regional assessment, we’ve conducted analysis of the barriers and opportunities that exist within the current policy and regulatory framework for
groundwater management. This information, combined with regional
assessments, will help us design statewide conservation actions.
We are also focusing efforts on groundwater conservation strategies at high
priority sites. We began by developing a methods guide for planners or site
managers designed to assist resource managers in understanding groundwater flow patterns, the connectivity between surface and groundwater and
hydrologic conditions required to sustain and enhance quality aquatic
habitats. The manual describes tools and approaches for 1) understanding
groundwater processes within a watershed, 2) identifying key ecosystems
and species that are groundwater-dependent, and 3) describing the
groundwater requirements of these ecosystems and species. Our site-level
work continues with case studies to design and test strategies for groundwater management to protect and restore groundwater-dependent
ecosystems and species.
The information generated from these approaches can be integrated into
environmental planning and management decisions to ensure that
groundwater is managed in a way that is compatible with the species
and ecosystems, while also meeting human needs of the region.
Project support
Springs at Borax Lake
© Allison Aldous/TNC
Project products
1. Maps depicting locations of
groundwater-dependent
ecosystems and species and
potential alterations to the supply
and quality of groundwater.
2. Tools and approaches for
conducting regional-scale
assessments linking groundwater
and biodiversity
3. Manual for integrating groundwater into conservation and
management plans
4. Case studies to design and test
strategies for groundwater
management that balance human
and ecological needs.
The Northwest Conservation Fund has provided major financial support for
this work; additional support has come from the Portland General Electric
and PacifiCorp Salmon Habitat Fund and the Laird Norton Foundation.
Many agencies and Conservancy programs have provided technical input,
including the U.S. Geological Survey, U.S. Forest Service, Bureau of Land
Management, Natural Resources Conservation Service, Oregon
Department of Environmental Quality, Global Conservation Approach Team
of the Conservancy and individual scientists from numerous Conservancy
chapters across the United States.
For more information
Leslie Bach, Phone: (503) 802-8146, e-mail: [email protected]
The Nature Conservancy
821 SE 14th Ave
Portland, OR 97214
Above, a sample decision tree diagram
developed to help land managers
quickly assess groundwater needs.
The Nature Conservancy is a leading conservation organization working around the world
to protect ecologically important lands and waters for nature and people. Learn more at nature.org/oregon.