Klamath Basin Rangeland Trust
Project: Analysis of Land Use Change on Groundwater
Location: Klamath Basin, Oregon
The KBRT is looking for additional water to meet irrigation demands, minimum
stage requirements for Upper Klamath / Agency Lake, and instream flow
requirements below the lake. To acquire this water, the trust has decided
to leave the irrigation water rights for its properties “instream”
and document the hydrologic benefits. Consequently, it has begun transitioning
irrigated lands to non-irrigated pastures in the Wood River Valley.
Because little was known about the shallow groundwater hydrology and aquifers
underlying the Wood River Valley, we needed to develop an initial conceptual
model using fundamental hydrogeologic data. This model would provide a
basis for developing other analyses and for designing the monitoring systems
required to document the hydrologic benefits of the land use conversion.
PGG served as the technical lead for hydrogeologic analyses, managing
a multidisciplinary team in establishing a comprehensive program for monitoring
water quantity and quality. We developed a network of stations for collecting
water quality samples, assessing fish and wildlife habitat, and monitoring
streamflows, spring flows, and shallow groundwater levels. To better understand
the groundwater system, we are measuring evapotranspiration (water lost
through evaporation and plant transpiration) under varying pasture conditions
and implementing a model to assess how return flows from irrigation affect
groundwater. The model will predict the timing and volume of these return
PGG has successfully represented the technical team in governmental, legal,
and stakeholder communications, including high-level federal communications.
Funding, which depends on quantifying the benefits of the land use change,
has been sustained for a third year.