State Water Resources Research Institute Program
Project ID: 2009ID138B
Title: Modeling Energy Implications of Water Management Decisions in the Upper Snake River Basin
Project Type: Research
Start Date: 3/01/2009
End Date: 2/28/2010
Congressional District: 1
Focus Categories: Management and Planning, Models, Hydrology
Keywords: Hydropower, River-Reservoir Model, Systems Dynamics, Snake River Basin, Surface and Ground Water Interaction
Principal Investigator: Johnson, Gary Steven (University of Idaho)
Federal Funds: $ 18,540
Non-Federal Matching Funds: $ 37,080
Abstract: Hydropower generation in the Pacific Northwest and use of the generated power is significantly impacted by competing water uses and associated water management planning in the upper Snake River basin. Up to 80% of the electrical power generation in the Pacific Northwest is produced by hydropower facilities, largely on the Snake and Columbia rivers. Power generation is impacted by the timing and magnitude of flows in the rivers which are in turn impacted by snowmelt runoff, reservoir management, irrigation diversions, and ground water returns to the rivers. Changes in water use and management, whether by design (e.g. management plans and reservoir operation rules) or incidental (e.g. caused by variation in crop prices), may alter flows through the river system and consequently the potential for electrical power generation. The Comprehensive Aquifer Management Plan (CAMP) for the eastern Snake River Plain targets adjusting water budgets by about 600,000 acre-feet/yr. Although flow of the Snake River will not be impacted to the same degree, even a change of 100,000 acre-feet/yr in river flow has the potential to produce a combined power generation and consumption effect of about 150 million kilowatt hours per year. To some degree, water managers are aware of the interconnection between water management and hydropower potential, but presently lack adequate tools to quantify the effects and express the impacts to the public.
River hydrographs are a result of the interaction of physical conditions controlling water supply and demand (i.e. runoff, evapotranspiration, aquifer conditions) with complex decisions distributing and allocating water for irrigation, flood control, recreation, and ecosystem services. In the Snake River system, the interactions of some of these relationships are simulated in the Fortran based Planning Model used by the Idaho Department of Water Resources and Idaho Power Company. The Planning Model, however, has limited ability to dynamically represent surface and ground water interaction and the logic is not easily understood by water interests and the public.
The goal of the proposed project is to evaluate the potential for systems dynamics modeling to: a) provide computational capabilities to reliably represent the dynamics of water flow and distribution in the Snake River above King Hill and the potential impacts of flow variations on hydropower generation and b) provide a visual representation and interface that communicates an understanding of simulated processes and results to a diverse audience. The STELLA systems dynamics software will be used to construct a prototype model. The water distribution portion of the model will be based on the existing IDWR Planning Model. Additional features and modification of the existing algorithm, determined in consultation with IDWR, will be added to the model to represent important aspects such as a dynamic representation of surface and ground water interaction. Hydropower generation estimation throughout the Columbia River System will be included in the additional features. The model will be verified by comparison of simulated flows and reservoir storage levels with measured monthly flows and storage for a historic period of at least 10 years.
The proposed model will provide a transparent and flexible tool to guide water management decisions as well as increase awareness and provide quantitative estimates of water management impacts on hydropower generation. The process and product of this research will also act as a catalyst for hydrologic and economic modeling activities of the recently funded National Science Foundation grant to Idaho universities addressing climate change.
Progress/Completion Report, 2009, PDF