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The Water Underground Reframing the Local Groundwater Picture Contents MARCH 2016 The Water Underground Reframing the local groundwater picture Contents 1 Executive Summary 12 Scenario 2: Areas with 16 Snapshot of the system declining supply 6 What is a sustainable 19 Recommendations water supply? CASE STUDY: REBATES – VICTORIA & WHITE BEAR LAKE, MN 24 Appendices 10 Scenario 1: Area has 14 Scenario 3: Areas with steady supply deficient supply CASE STUDY: ENCOURAGING CASE STUDY: WISE PLANNING – effiCIENCY – SHOREVIEW, MN TUCSON, AZ Foreword Ask any city engineer to list the primary goals plus routine equipment replacement, meter they have for their city’s public water supply upgrades, residential efficiency incentives, system and their overwhelming answer industry efficiency incentives, and systematic comes back as “safe and reliable.” Pushed leak assessment programs — most of us for a third goal they would likely add, “and would still be paying less than our cable bill. under local control.” We can live without cable. For the most part, Minnesota’s water man- Public water suppliers choose what level agement system is among the best in the of service to provide their customers and nation and wisely provides local governments how much of that cost to include in their rate. (and their utilities) sufficient authorities to Trying to compare rates with neighboring shape their water destiny — that is, until they suppliers is tempting but ultimately not very demonstrate they cannot or will not manage useful unless it is known what costs they are water issues for the long haul. including or deferring. A formal rate study that addresses full system costs and anticipates A growing number of communities continue increased water efficiencies will minimize to over-pump drinking water from declining surprises from special assessments, system aquifers while dreaming of further population failure liabilities, or intervention from higher increases and economic expansion. The levels of government. realities and the dreams don’t match; available supplies won’t support future demands unless With the small, undramatic measures identi- the community actively manages the situation. fied in this report, many water suppliers could stabilize their supplies so as to remain safe, Effective management requires sufficient reliable, and under local control for the funding. Currently, we pay very little for long term. drinking water services. If a water supplier were to charge for full system costs — pump- ing, treatment, storage, and distribution EXECUTIVE DIRECTOR Executive Summary Despite Minnesota’s long-standing identity as a water-rich state, we can no longer assume that our groundwater supplies are adequate everywhere to meet future demands. Aquifer levels are declining in multiple spots, adversely impacting communities and impeding economic growth. Moreover, unlike water crises playing out in southern and western states, these local declines are not caused by severe drought, nor would one be necessary to draw down reserves further. Minnesota has devised a system of shared groundwater management. Public suppliers Public water suppliers, given their critical influence over local ground- have the most to water supplies through planning, rate, and infrastructure management, can significantly change the long-term adequacy of local supplies to lose if, or when, meet future needs. On the other hand, the Department of Natural local groundwater Resources (DNR), given its charge to ensure that groundwater use is resources decline sustainable, may be compelled to take a more active role in limiting or managing usage based on projected or documented declines, and significantly. threats to natural resources. Public suppliers have the most to lose if, or when, local groundwater resources decline significantly. Local measures taken now can improve the effectiveness and authority of their management, and ensure the long-term availability of groundwater supplies. In this report, we present recommendations to improve local groundwater management. Underlying our recommendations is the need to frame the urgency level required in local management, based on an assessment of the current state of local supplies. We propose three possible urgency-level scenarios that illustrate the range of current realities in Minnesota communities and thereby frame local management recommendations: The Steady Scenario The Declining Scenario The Deficient Scenario Communities where water reserves Communities where groundwater Communities where there are are in equilibrium and sufficient to levels show long-term downward immediate concerns about ground- keep up with current usage into the trends. Water supply is not an water limitations. Immediate action future. Urgency level for increased issue today, but without changes, is needed to prevent a crisis. management is low. Priority should future use will be limited. Urgency Urgency level for considerably be placed on management for level for additional management increased management is high. long-term sustainability goals. is moderate. Thankfully, most Minnesota communities are in the “steady scenario,” and fewest are in the “deficient scenario.” Regardless of scenario, the ranges of possible actions are similar. We use this framework to inform and forge a common understanding of the urgency level required from management. THE water UNDERGROUND Reframing the local groundwater picture 1 Minnesota’s overall abundant groundwater supply is an asset that supports local and state economies, communities, and ecosystems, but it must be valued, understood, and intentionally managed for sustainability if it is to support future generations. Strengthening and establishing clear priorities for Adjust water rates to recover full-system the local management of groundwater resources is costs. Recovering the full cost to deliver water critical if Minnesota is to take the path of long-term to customers allows a city to provide a water water availability. The recommendations for public supply that is reliable, safe, and adequate for water suppliers and state leaders are as follows: generations. Rates should cover the cost of treatment and distribution, but also programs to reduce system losses, increase customer For Public Water Suppliers efficiency, provide for system replacement 1. Assess local groundwater trends (steady, and maintenance, and provide an emergency declining, or deficient scenario) and the reserve. Modest rate adjustments would current state of the water system. Conduct likely have minimal impact on the majority a water audit to categorize and track usage of customers, but could raise revenue to from season to season. Obtain existing finance system improvements and ensure information about aquifer levels and trends. long-term adequacy. Assess customer usage needs and the condi- Utilize and improve tiered customer tion of the water infrastructure. Using this rates to incentivize efficiency. Tiered water information, determine as realistically as rates incrementally increase the price per possible the groundwater scenario that best gallon as water use increases sending a fits the local system. signal to users to use water more efficiently. 2. Depending upon the identified urgency level, Expand groundwater management beyond manage for immediate supply improvement the water utility. The primary responsibility or long-term supply maintenance, selecting for managing groundwater in many commu- from the strategies recommended below. nities may lie with the public water supplier, but suppliers do not operate in isolation. Reduce system losses. Reducing water Partner with neighboring communities and losses from within the distribution network other large users to cooperatively manage helps a utility stretch its supply and recover the shared groundwater resource and lost revenue. We recommend funding a loss diversify supplies. They should also break control program as an initial measure. down internal planning silos to integrate Increase customer water use efficiency. groundwater management with overall city Increased efficiency represents the biggest development goals. opportunity for many communities to stretch existing groundwater supplies. Tailor water efficiency programs to the customer base and the challenges faced by THIS REPOrt — focusing on management the public water supplier. Options include recommendations to public water suppliers and improved metering systems, programs state agency and elected leaders — is the first of targeted to household, commercial, and three the Freshwater Society will release in 2016-17. industrial users, and using water rates Subsequent reports will address ways to extend to incentivize efficiency. supplies (reuse and aquifer recharge) and ground- water issues associated with crop production. 2 Freshwater SOCIETY every drop matters Lost Water 40 45 40 Domestic Public 130 100 105 Surface Systems Surface 1,160 70 1,200 Water 25 65 Commercial/ 60 Water Industrial 25 50 85 20 Agriculture (Irrigation and 15 Livestock) 80 5 30 Mining Ground 290 100 75 water Consumed/ 215 1 60 Evaporated Thermal Electric 950 890 Diagram shows approximate proportions of water use in Minnesota. This report focuses on public systems that are the largest user of groundwater. A negligibly small portion of water used returns to groundwater. Values may not add up due to rounding errors. All values are millions of gallons. SOURCES: MN DNR, MDH, US EPA, AWWA For State Leaders 1. Continue filling gaps in monitoring, modeling, on a predictable funding base and lessen research, and communication necessary to reliance
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