Integration of Project-Scale and Basin Wide Water Management: an Application in the Klamath Project
* If irrigation district scale decisions on water source and cropping patterns are modeled dynamically with river basin scale decisions on water allocation and reservoir operations, what influence will the combined perspectives have on Reclamation annual operations and long term planning in a setting like the Klamath Project?
* How can this or similar analysis tools best be integrated with the Western Water Information Network (WWIN) enterprise Geographic Information System (GIS) display system and the Integrated Information Management System (IIMS) to effectively communicate study results to the widest range of stakeholders?
This Science and Technology (S&T) Program research project will link reservoir operations and district-scale water management in a single package to support Reclamation's planning and decision making in the Klamath Basin and will provide a template for similar modeling advances in other applications. It will also provide a test case for extending the display capabilities of the WWIN program to decision support tools.
Need and Benefit
Many river system management models used by Reclamation evaluate reservoir operations based on available surface water supplies and water demand, as limited by physical and regulatory constraints. Often, these models rely upon external analyses for critical inputs. For example, surface water demand time series are typically based on assumptions about cropping and water management practices at the water district scale. This approach rests on the assumption that these practices can be determined _a priori_ and that they are essentially independent of the availability of surface water. This assumption limits the value of these analyses in situations where practices may in fact react dynamically to the evolving status of surface and ground water supplies and economic conditions.
This is currently the case for the Klamath Project, where the existing model releases water from upstream reservoirs in response to static project scale representation of water demand, and return flows to the Klamath River through the Klamath Straits Drain are represented as historic data.
There are a number of important issues in the Klamath Project which are left unresolved by this modeling approach. Cropping decisions are influenced by anticipated production levels and associated economic value. Water bank participation is influenced by financial incentives and access to ground water sources. These water management decisions in turn affect the management of Tule Lake, Lower Klamath Lake, and associated facilities. These issues combine to influence the quantity, quality, and timing of impacts to the Klamath River. Project management challenges in the basin have seen increasing changes in recent years, and there is a clear need for analytical capabilities to keep up.
In 1999 Reclamation contracted with University of California, Davis to develop a representation of water management within the Klamath Project. The result of this effort was Klamath Basin Hydrology and Economics Model (KBHEM), a model that used the surface water delivery time series generated by the planning model, along with regional economic functions, as the basis for simulating cropping and water management practices within the Klamath Project. KBHEM was capable of addressing many of the issues outlined above, but it was not dynamically integrated with the planning model, and due to evolving study needs has not been used to its existing potential. It provides a solid foundation upon which to develop the more flexible and comprehensive modeling tool which is now needed.
This type of model is a natural fit for a demonstration of decision support system integration with the Western Water Information Network (WWIN), an enterprise GIS system under development through Reclamation's S&T program. To date, the WWIN effort has concentrated on representing historical data in a georeferenced, scalable, internet accessible format. Extending WWIN's applicability to display modeled information will provide a valuable platform for assisting Reclamation and stakeholders in the decision process. KBHEM produces predominantly spatial output (cropping patterns, irrigation practices, ground water impacts, production level, water sources, etc.) that could be handily displayed in a georeferenced format. The WWIN program would like to use this type of model as a test case for Decision Support System (DSS) integration.
Contact the Principal Investigator for information about these documents.