Regional Groundwater Modeling: Metro Pumping Optimization
As the Metropolitan Council updated the Twin Cities Metropolitan Area Master Water Supply Plan, stakeholders asked the Council to consider the sustainable limits of the region’s water sources. The Council’s most important analytical tool is a regional groundwater flow model (Metro Model 3), which can be used to quantify the long-term regional impacts caused by hundreds of independent groundwater appropriations. Similar to what has been done in other parts of the United States, the regional groundwater model can also be optimized to maximize groundwater withdrawals without violating user-defined sustainable water resource constraints. This project evaluated the feasibility of optimizing Metro Model 3 to estimate the sustainable limits of the region's groundwater sources.
The project generated:
• Optimized MODFLOW model files
• Optimized optimization files
• A technical memo
(c) $1,000,000 the first year and $1,000,000 the second year are for metropolitan regional groundwater planning to achieve water supply reliability and sustainability, including determination of a sustainable regional balance of surface water and groundwater, a feasibility assessment of potential solutions to rebalance regional water use and identify potential solutions to address emerging subregional water supply issues such as the northeast metro, and development of an implementation plan that addresses regional targets and timelines and defines short- and medium-term milestones for achieving the desirable surface water and groundwater regional balance. By January 15, 2014, the commissioner shall submit an interim report on the expenditure of this appropriation to the chairs and ranking minority members of the house of representatives and senate committees and divisions with jurisdiction over environment and natural resources finance and policy and the clean water fund.
This project proposes to determing the capability and limitations of using Metro Model 3 for optimization modeling.
Final outcomes will be reported at project completion.
(c) $1,000,000 the first year and $1,000,000 the second year are for metropolitan regional groundwater planning to achieve water supply reliability and sustainability, including determination of a sustainable regional balance of surface water and groundwater, a feasibility assessment of potential solutions to rebalance regional water use and identify potential solutions to address emerging subregional water supply issues such as the northeast metro, and development of an implementation plan that addresses regional targets and timelines and defines short- and medium-term milestones for achieving the desirable surface water and groundwater regional balance. By January 15, 2014, the commissioner shall submit an interim report on the expenditure of this appropriation to the chairs and ranking minority members of the house of representatives and senate committees and divisions with jurisdiction over environment and natural resources finance and policy and the clean water fund.
The capability and limitations of using Metro Model 3 for optimization modeling will be determined.
This project demonstrated that Metro Model can be used for optimization modeling. Under the assumptions set forth in the Twin Cities Metropolitan Area Master Water Supply Plan, optimization modeling suggests that the region might sustainably withdraw approximately 400-500 million gallons of groundwater per day in areas where high-capacity wells currently exist. However, even when groundwater withdrawals are less than that, local limitations may still exist due to proximity of sensitive local features such as neighboring wells or a trout stream.
Project results are included in the Twin Cities metropolitan area Master Water Supply Plan, which can be found online at http://www.metrocouncil.org/Wastewater-Water/Planning/Water-Supply-Plan…
Gary L. Cunningham, Cara Letofsky, Edward Reynoso, Marie McCarthy, Sandy Rummel, Harry Melander,
Richard Kramer, Jon Commers, Steven T. Chávez and Wendy Wulff