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Draft North& East Metro Groundwater Management Area Plan 4-3 Groundwater-Level Data and Trends Monitoring groundwater levels is an important element of groundwater management and ensuring compliance with the safe yield thresholds. Levels must be viewed in the context of natural climate fluctuations and groundwater pumping history. Since 1944 the DNR has managed a statewide network of dedicated water-level observation wells. Water-level readings from these observation wells are available on the DNR web page. There are 60 actively measured obwells within the GWMA boundary area (Figure 4-2). Nineteen of these wells have been constructed since 2009 and provide only short records. Some appropriation permit holders also maintain observation wells as required in permit conditions. Other organizations have also installed observation wells. For example the Valley Branch Watershed District measures water levels in 15 shallow observation wells three times per year. Historical data from inactive or sealed obwells and from obwells outside the GWMA provide additional useful information about changing groundwater levels over time. DNR staff reviewed data from obwells throughout the state for statistically significant trends in annual minimum water levels for the 20-year period from 1993 through 2012. Nineteen wells at 14 locations in the North & East Metro GWMA had sufficient data for analysis (three locations include 'nested' obwells of different depths). Four of these obwells had upward trends; three had no trend; and 12 had a downward trend (Figure 4-2). In general,the available obwell data indicate that recent groundwater levels have been near or below low points of the previous 30 years regardless of proximity to areas of intensive groundwater pumping (with the exception of rising groundwater levels in parts of Ramsey County as a result of reduced pumping).This leads to the conclusion that weather was a major factor in recent lower groundwater levels in the vicinity of the GWMA. Lower water levels in areas where groundwater use has substantially increased over the last 20 years appear to reflect a combination of climate and pumping effects. At observation wells completed in artesian aquifers, water levels are not approaching safe yield thresholds. P61