An evaluation and review of water-use estimates and flow data for the Lower Klamath and Tule Lake National Wildlife Refuges, Oregon and California

Evaluation of alternative groundwater-management strategies for the Bureau of Reclamation Klamath Project, Oregon and California

“…Studies by Burt and Freeman (2003) and Risley and Gannett (2006) highlighted the importance of irrigation return flows to the operation of the Project, which has about 700 mi of drains that collect return flows that can then be recycled for irrigation in downslope areas of the Project or routed to wetlands in the Lower Klamath and Tule Lake National Wildlife Refuges. Irrigation return flows are a substantial, although not quantified, water supply for some downslope irrigation districts and the re-use of return flows significantly increases the Project-wide irrigation efficiency (Burt and Freeman, 2003).…”

“…In the Project, irrigation return flows are recirculated through the drain system and can be a significant water supply for downslope irrigators. Irrigation return flows also are used to maintain permanent and seasonal wetlands in the Tule Lake and Lower Klamath National Wildlife Refuges (Burt and Freeman, 2003;Risley and Gannett, 2006). Any groundwater discharge diverted from the drain system by pumping will reduce the amount of water available for irrigation and delivery to the refuges.…”

Use of models and observations to assess trends in the 1950–2005 water balance and climate of Upper Klamath Lake, Oregon

“…In addition, adequate field data for validating the ET computations do not exist at UKL. For this analysis, an evapotranspiration rate of 85% of the simulated open water evaporation rate for UKL [ Risley and Gannett , 2006] was specified, which yielded a mean annual wetland ET of 912 mm (0.072 × 10 9 m 3 over the mean lake area). Losses through ET thus account for only about 3.5% of total loss in the lake water balance.…”

“…In addition, adequate field data for validating the ET computations do not exist at UKL. For this analysis, an evapotranspiration rate of 85% of the simulated open water evaporation rate for UKL [Risley and Gannett, 2006] was specified, which yielded a mean annual wetland [Daly et al, 1994], (d) combined discharge from UKL in the Link River and A-Canal, (e) Simulated evaporation from the lake model, and (f) water volume computed for simulated evaporation (thick line) and estimated from using a fixed pan value of 1057 mm a À1 . Irrigation data from Risley and Laenen [1998] and the Oregon Water Resources Department Water Right database (http://www.wrd.state.or.us/OWRD/WR/wris.shtml).…”

Water-quality modeling of Klamath Straits Drain recirculation, a Klamath River wetland, and 2011 conditions for the Link River to Keno Dam reach of the Klamath River, Oregon

“…Ady Canal flows in the opposite direction, withdrawing water from the Klamath River and delivering it to agricultural lands and the Lower Klamath National Wildlife Refuge, which has permanently flooded wetlands, seasonal wetlands, agricultural lands, and upland habitat (Mayer, 2005). A water budget developed for years 2003-05 for this refuge was used to estimate that Ady Canal supplied 25 percent of refuge inflow (Risley and Gannett, 2006). That study also determined that other refuge inflows in those years included pumped flow from Tule Lake (36 percent), precipitation (21 percent), and creek inflow (18 percent).…”