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Draft North & East Metro Groundwater Management Area Plan 4-1 4. Status of the GWMA in Terms of the Objectives This section describes our current understanding of the status of the North & East Metro GWMA with respect to the five objectives described in Section 3. Based on the five objectives,the definition of sustainability with respect to groundwater is that use: • Does not harm aquifers and ecosystems • Does not negatively impact surface waters t is reasonable, efficient and meets water conservation requirements • Does not degrade water quality • Does not create unresolved well interferences or water sue conflicts All of the sustainability objectives must be achieved to attain overall sustainability of groundwater use in the GWMA. The status described is based on currently available information and an assessment of information and data gaps. The gaps need to be addressed to meet long term goals of groundwater sustainability in the GWMA. The status of each objective is briefly summarized below. Objective I. Aquifers, Ecosystems and Surface Waters Groundwater, surface waters and groundwater-dependent ecosystems are interrelated. Groundwater levels fluctuate in response to a number of influences including climate, land use, and groundwater pumping. Managing for groundwater-use sustainability requires quantitative knowledge of the influences on groundwater and its connection to surface water. Two types of information are needed to make water-appropriations permitting decisions that protect aquifers, surface water resources, and associated biological communities. First, acceptable levels of hydrological impacts must be determined for each type of feature. General considerations are discussed in Section 3.0, but site specific thresholds may be needed for particular surface-water features. Second, an estimate of how and the degree to which existing or proposed water appropriations may change the hydrological regime must be made. The projected or interpreted impacts may then be compared to the established thresholds. Climate Data and Trends The main driver of groundwater recharge variations is climate.The climate in the North & East Metro GWMA is characterized by variable weather.The 'normal' condition is for substantial ups and downs in precipitation, evaporation, and other climatic factors that affect hydrology.The hydrologic effects of climate must be understood before one can assess the hydrologic effects of groundwater use. Although longterm average annual precipitation has been higher in the Twin Cities since the mid- eighties compared to the previous decades, the Twin Cities experienced relatively lower precipitation in parts of the last decade. For example, the 1981-2010 'climate normal' precipitation at the Minneapolis- St. Paul International airport(red line on Figure 4-1) is higher than 30-year climate normal for previous P59