The Wood River Basin lies upstream of Upper Klamath Lake, the main reservoir of the USBR Klamath Irrigation Project that provides irrigation water to 210,000 acres of downstream land. Water allocation became a contentious issue in 2001 when drought led to curtailment of irrigation deliveries to the Klamath Irrigation Project in order to maintain minimum lake levels and river flows for endangered species. After lengthy negotiations the Klamath Basin Restoration Agreement was signed in February 2010, and calls for flow increases of 30,000 ac-ft/yr into Upper Klamath Lake from voluntary upstream sources. The Wood River Basin is a potential source of this water, but poorly understood hydrology makes estimates of water gains in response to conservation strategies uncertain. To better understand the hydrology of the Wood River Basin a fully distributed, physically based model was set up using the MIKE SHE hydrology model and MIKE 11 hydraulic model by DHI, Inc. The model was developed by recreating the actual management of the basin from 2002 to 2009, a period when tracts of land in the basin were enrolled in land idling programs for water conservation. Calibration and validation was evaluated against shallow groundwater observations. Overall the model described the average conditions of the basin well. Locations that were simulated inaccurately were limited to those in close proximity to the model boundary or to the Wood River, the result of using average values to describe these heterogeneous features. The model was used to simulate two end-member scenarios to determine the limits of water conservation strategies, basin-wide full irrigation and non-irrigation. Two reduced irrigation scenarios were also simulated, the first reduced the irrigation season to June and July, the second eliminated every other irrigation application. The simulation that recreated the actual management showed that non-irrigated tracts did not substantially reduce the consumptive use because water from the surrounding irrigated tracts was able to flow in via the shallow aquifer and provide sub-irrigation. For the full irrigation scenario the average annual consumptive use was 126,000 ac-ft/yr. For the non-irrigated scenario it was 96,000 ac-ft/yr, a reduction of 24%. For the two reduced irrigation scenarios the consumptive use was decreased by 14% and 12%. When compared to the irrigated scenario the total increase of flow to Upper Klamath Lake during the growing season was 60,000 ac-ft/yr for the non-irrigated scenario; and 36,000 ac-ft/yr and 31,000 ac-ft/yr for the two reduced irrigation scenarios respectively. Irrigation in the basin was found to transfer stream flow from the summer time to the winter time due to saturated winter conditions from late season irrigations resulting in increased runoff. There is potential for water conservation strategies in the Wood River Basin to substantially increase water flow into Upper Klamath Lake, but these strategies would have to be implemented extensively throughout the basin to reduce sub-irrigation.