A cooperative study was conducted by the U.S. Geological Survey (USGS), the Metropolitan Council, and the Minnesota Department of Health to assess groundwater and surface-water interactions in lakes in the northeast Twin Cities Metropolitan Area (TCMA), including White Bear Lake. An important product of the study was the creation of a groundwater-flow model focused on the northeast TCMA. The groundwater flow model is available for future use to assess the effects of groundwater withdrawals on lake levels as well as to describe other groundwater and surface-water interactions.
The State Fiscal Year 2014-2015 Clean Water Fund appropriation identified the northeast metro as an area where potential solutions are needed to address emerging water supply issues. The Metropolitan Council, in conjunction with S.E.H. consultants, evaluated water supply approaches to serve the northeastern part of the Twin Cities metropolitan area. A subregional study areas was selected based on the indication of potential problems with the long-term sustainability of current water supplies, as well as expressed interest by community stakeholders.
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.
The Metropolitan Council and City of Saint Paul cooperated on a rainwater harvesting and reuse system in downtown Saint Paul. Rainwater from the northern half (2 acres) of the roof at the new Metro Transit Green Line Operations and Maintenance Facility (OMF) is captured using a modified version of the existing OMF rainwater collection system. The existing collection system was re-designed to convey rainwater to the new Lowertown Ballpark, home of the Saint Paul Saints, where uses include ball field irrigation and toilet flushing.
State law charges the Metropolitan Council (Council) with developing and maintaining a base of technical information needed for sound water supply decisions (Minnesota Statutes 473.1565). The Council’s primary tool to provide this information is the Metro Model 2, a regional groundwater model capable of predicting the impacts of planned water demand on aquifers and connected lakes and streams. The Metro Model 2 is a modern and comprehensive groundwater model of the Twin Cities area, but it is currently out-of-date.
Regional recharge modeling with the Twin Cities daily soil water balance (SWB) model has been a fundamental part of the Metropolitan Council’s groundwater flow modeling effort and supports the Metropolitan Area Master Water Supply Plan. The SWB model is used to evaluate the impact of planned and potential land use and climate on recharge in the eleven-county metropolitan area, and supports the ongoing update of the regional groundwater flow model.
The Metropolitan Council, in conjunction with CDM Smith and HKGi consultants, reorganized and expanded the water conservation tools on the water supply planning pages of the Metropolitan Council’s website. The revised toolbox was organized into an online, web-based guide format. These tools are supplemented with fact sheets and case studies that serve to educate and provide useful information to support water conservation programs and activities.
The Metropolitan Council, in conjunction with CDM Smith consultants, undertook a project to collect and disseminate data regarding water costs and conservation programs in the seven-county metropolitan area, including:
• Evaluating all water rate structures of the communities in the seven-county metro area. The information on rates by community is correlated with community per capita values, peaking ratios, and other water use characteristics.
• Evaluating all water conservation programs in the communities in the seven-county metro area.