Tuesday, April 13, 2010: 4:20 p.m.
Continental B (Westin Tabor Center, Denver)
In the 1970’s Arizona developed a model to evaluate and optimize potential allocations of surface water from the Colorado River. Arizona had recently obtained a Supreme Court judgment in Arizona v. California quantifying Arizona ’s allocation.
Arizona ’s congressional delegation began work on obtaining the federal funding necessary to construct the Central Arizona Project (CAP), a conveyance system to transport Colorado River water. The state realized it had never thought through exactly what they would do with the water and how it would repay the borrowed federal money. The Governor and the delegation needed viable technical support to sustain their arguments for funding.
Arizona Water Commission technical staff created a model consisting of several major groundwater basins as candidates for CAP allocations. Basin selection was driven primarily by massive unsustainable mining of groundwater. The groundwater basin models were linked to a linear program (LP) optimization model that simulated varying allocations delivered to any of the modeled basins via the CAP. The LP also linked agricultural economic factors such as crop type, crop value, crop costs and electrical power costs vs. lift for delivery of both surface water and ground water. The ultimate goal was to use the CAP water in the most economically efficient way possible to aid in generating repayment revenues while optimizing surface and ground water use to mitigate the problems associated with severe groundwater mining.
The model allowed a huge array of possible scenarios for allocation of CAP water to competing users over a very large geographic area and also provided political support for negotiations with Congress over funding the CAP. The CAP was built and the rest is history. While the tools are now dated, the concepts and the wide variety of interests involved in water resource allocation and use optimization in the West have not changed significantly.
Arizona Water Commission technical staff created a model consisting of several major groundwater basins as candidates for CAP allocations. Basin selection was driven primarily by massive unsustainable mining of groundwater. The groundwater basin models were linked to a linear program (LP) optimization model that simulated varying allocations delivered to any of the modeled basins via the CAP. The LP also linked agricultural economic factors such as crop type, crop value, crop costs and electrical power costs vs. lift for delivery of both surface water and ground water. The ultimate goal was to use the CAP water in the most economically efficient way possible to aid in generating repayment revenues while optimizing surface and ground water use to mitigate the problems associated with severe groundwater mining.
The model allowed a huge array of possible scenarios for allocation of CAP water to competing users over a very large geographic area and also provided political support for negotiations with Congress over funding the CAP. The CAP was built and the rest is history. While the tools are now dated, the concepts and the wide variety of interests involved in water resource allocation and use optimization in the West have not changed significantly.