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Draft North & East Metro Groundwater Management Area Plan 4-9 improve understanding of groundwater-lake interactions in the northeastern Metro area.The results of the study will be useful for prioritizing evaluation of groundwater pumping impacts. Gap Analysis and Recommendations Aquifers The safe yield definitions in Minn. Rules, part 6115.0630 are the criteria used to evaluate the sustainability of aquifer levels in the North & East Metro GWMA.Safe yield defines sustainability of long term water storage in the aquifer system and the capacity of the aquifer system to supply water. There are sufficient data available to evaluate compliance with safe yield at recent pumping rates in the North & East Metro GWMA.There are no indications that recent pumping rates present a risk for exceeding safe yield in the North & East Metro GWMA.This is supported by the available observation well data and water-level measurements in other wells. Metro Model 3 results also indicate that total pumping rates are below estimated average recharge for the aquifers included in the GWMA. Continued collection of data from the obwell network, water use reports, and climate stations will allow for early detection of trends. Observations reflect impacts of current and historical climate and land-use changes in addition to pumping history. Continued growth in groundwater demand is expected for parts of the GWMA, particularly in growing suburbs in Anoka and Washington counties.Additional obwell locations and climate stations may be needed to improve assessment of climate conditions, aquifer level sustainability and other management objectives. The Metropolitan Council's new regional model (Metro Model 3) may serve as the foundation for improved assessments of future risk. Additionally, data collection and analysis typically required for new or amended permit evaluations, such as performing and analyzing aquifer pumping tests, will also provide more information where needed. Further work is needed to evaluate the risk of exceeding safe yield under potential future scenarios. Ecosystems and Surface Waters Appropriations from water basins (lakes and wetlands) listed in Bulletin 25 are limited by statute to a total annual volume of water amounting to% acre-foot per acre of water basin (6-inch depth over the surface area). While this limit is protective of some water basins, it is likely not sufficient to prevent negative impacts to all water basins and biological communities associated with water basins in the North & East Metro GWMA. Site specific thresholds may be appropriate for some sensitive features likely to be influenced by groundwater appropriations. As discussed above,the available information allows for comparing the relative vulnerability of different water basins. Improved methods for determining the hydrological impacts of groundwater pumping on basins are under development, and additional studies are underway to identify basins particularly sensitive to appropriations. Improved methods for determining the hydrological impacts of groundwater pumping on flow in water courses are also under development. Site specific maximum diversion thresholds are needed for 67