Water Supply Planning for the Twin Cities Metropolitan Area Brian Davis, Ph.D., P.G., P.E. Senior Engineer, Metropolitan Council

Metropolitan Council Environmental Services 640 miles of interceptors 8 wastewater treatment plants Environmental monitoring Water supply planning

Water Supply Planning Facilitate collaboration Support local plans Technical support Water conservation Reusing stormwater and treated wastewater Support regional and local investments Details about the strategies the Council is using to achieve the vision are included in Chapter 7 of the Master Water Supply Plan. 1) The Metropolitan Council will collaborate with state agencies, watershed organizations, and community water suppliers to update the regional Master Water Supply Plan as new information becomes available and as the comprehensive development guide for the metropolitan area, Thrive MSP 2040, is updated. 2) The Council promotes water sustainability through the Master Water Supply Plan, and through the review of local water supply plans, surface water management plans, comprehensive plans, and comprehensive sewer plans. The Council will review and comment on plans. 3) In partnership with others, the Council will: Fill gaps in technical assessments of lake, stream, river, and groundwater data; Maintain a regional database that contains easily accessible water quality, quantity and other water related information collected as part of the Council’s monitoring programs; Complete technical studies to understand regional and sub-regional long-term water supply availability and demand including modeling and other approaches; Support community efforts to identify and evaluate the economic and technical feasibility of water supply approaches and best practices that increase water conservation, enhance groundwater recharge, and make the best use of groundwater, surface water, reclaimed wastewater, and stormwater. 4) The Metropolitan Council will facilitate discussions on water supply issues that transcend community boundaries, though sub-regional work groups and on an ad hoc basis as needed. 5) The Metropolitan Council will promote and support water conservation measures, including education, outreach and tool development. 6) Metropolitan Council will investigate reusing treated wastewater to supplement groundwater and surface water as sources of nonpotable water to support regional growth, and when cost-effective, implement reuse. 7) Metropolitan Council will support cost-effective investments in water supply infrastructure to promote efficiency and sustainable use and protect the region’s water supply

Metropolitan Area Water Supply 3 million people 186 communities, 106 water supply providers 70% of residents use groundwater Municipal water use: Current: 300 million gallons per day Projected (2040): 450 million gallons per day

What Makes Us Different

Municipal Water Sources Groundwater Source Area Twin Cities Basin Groundwater Source Area Mississippi River Source Area 6 The source of the metro region’s municipal water supplies comes from an area that extends beyond the Metropolitan Council’s jurisdiction in the seven-county metropolitan area. While our groundwater supplies are located mainly in the seven-county metro, the aquifers that supply them extend beyond the county borders. In addition, the primary source are for the Mississippi River intakes that provide water to Minneapolis Water Works and St. Paul Regional Water Services – the drinking water providers for 40% of the metro’s residents – is located almost entirely outside of our seven counties. What we do control entirely within our jurisdiction is the treatment and discharge of all of the surface water and groundwater used in the seven-county metropolitan area. Most of this water is treated and discharged at one of the regional wastewater treatment plants (green squares). Interesting fact: the amount of wastewater treated every day in the metro is more than double the amount of water used by industry in the metro. This combination of surface water and groundwater supplies, and multiple regional wastewater treatment plants, make the Twin Cities is a little different than other parts of the state. In many ways, we have more flexibility for managing water supplies. We have greater potential for conjunctive use of groundwater and surface water, and reuse of reclaimed wastewater. But it also means our drinking water supply planning is complicated by limited authority over our source water areas, the significant consequences of significant contaminant spills in the Mississippi River watershed, and competition with other very large private Mississippi River water users – particularly during droughts – such as the power plants that supply energy to the entire state.

Four Extensive Aquifers We are lucky to have… Four extensive underground layers of rock, gravel and sand (aquifers) hold and transport billions of gallons of water for over two million people.

Metro Area Wells Drilled from 1940 - 2010 (800) (60,000) Darker blue = older well 1940-2010 data reported for 7-County Metro in 2013 Minnesota County Well Index

Mississippi River We are lucky to have… Four extensive underground layers of rock, gravel and sand (aquifers) hold and transport billions of gallons of water for over two million people.

Groundwater and Surface Water Over time, our use of these sources has grown. In the 1970s and 1980s, the region drew water equally from the Mississippi and from groundwater. But today, three out of four people use groundwater. That’s because most of the region’s development expanded to areas away from rivers. Now, we use more groundwater compared to surface water.

Growing Population Increases Municipal Water Use

Over time, our use of these sources has grown. In the 1970s and 1980s, the region drew water equally from the Mississippi and from groundwater. But today, three out of four people use groundwater. That’s because most of the region’s development expanded to areas away from rivers. Now, we use more groundwater compared to surface water. City of Eden Prairie

Monthly Cost

Monthly Residential Use

Monthly Residential Use

Minneapolis

Residential Water Use

Residential Indoor Water Use 138 gallons per household per day 58.6 gpcd Water Research Foundation

Residential Indoor Water Use Water Research Foundation

Outdoor Water Use

Outdoor Water Use 1990s

Hospitals Name City/Rank Million Gallons/Year Abbott Northwestern Minneapolis/3 53.3 VA Medical Center Minneapolis/4 53.0 Regions Hospital St. Paul/5 65.3 United Hospital St. Paul/8 39.3 Lakeview Hospital Stillwater/1 10.0 Fairview Ridges Hospital Burnsville/2 29.9 Mercy Hospital Coon Rapids/1 35.5

Issues of Concern Aquifer Drawdown Excess Infrastructure Aquifer Contamination Source Water Protection

Aquifer Drawdown

Aquifer Drawdown 2040 pumping vs. today Institute for Groundwater Research

Aquifer Drawdown 2040 pumping vs. today

Effects on Surface Water

Excess Infrastructure

Irrigation Gets Smart!

Let’s Do An Experiment!

13,643 gallons vs. 1,671 gallons

$2 Million in Potential Savings

Aquifer Contamination Perfluoroalkylated Substances www.sixclasses.org

Aquifer Contamination

Aquifer Contamination MDH

700,000,000 lb/year StarTribune

Source Water Protection

Thank You!