LESSONS LEARNED FROM TWO DECADES OF GROUNDWATER MONITORING IN THE UPPER KLAMATH BASIN

Competing demands for limited water in the upper Klamath Basin of Oregon and California can make it difficult to balance the needs of farmers, ranchers, municipalities, and tribes with those necessary to sustain fish and wildlife. Groundwater is an important part of this limited resource. To monitor changes in groundwater levels, including declines related to groundwater pumping, a monitoring network of wells was established throughout the basin in the early 2000’s, and has been monitored quarterly for nearly two decades. Water-level data collected from this network have been used in reports detailing the groundwater hydrology of the upper Klamath Basin, and in a report relating changes in groundwater level to groundwater pumping on the Bureau of Reclamation Klamath Project. These investigations showed that the groundwater resources of the upper Klamath Basin are impacted by climate and pumping. Using the earlier comprehensive studies for context, this talk evaluates trends in groundwater during the last 20 years. Questions considered include: How have groundwater levels responded to changes in basin-wide water management during this period? How have groundwater levels responded to climate and changes in pumping? Has the monitoring illuminated new questions and challenges to be resolved?