01-10-1994 Council Packet - Laserfiche WebLink

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this with precipitation daU from nine sites. These additional sites help show the variability of precipitation across the watershed. The northeast comer of the watershed averages four inches more precipiution per year than the southwest comer. Total precipitation volumes help calculate water budgets for the District. These data help size stermwater detention and conveyance structures. Ground Water Monitoring In 1972. the MCWD began collecting water quality and quantity data from nine municipal and private wells in or near the watershed. Although two of the wells ^e no longer in service, the MCWD now has over 20 years of data from the remaining 7 wells. Water level data from a long period of time shows a variety of water table trends. For example, it can show if the water table is naturally replenishing itself or if wells are depleting the water table faster than the natural recharge rate. Combined with precipitation data, well records can help quantify recharge, runoff and seepage rates. Lake Monitoring The MCWD collects water quality data necessary to show a lake’s relative water quality. This way, we can compare the lake to other lakes and also evaluate its condition time. Lake water quantity data helps predict inflows, runoff levels, and subi^crshed water budgets. It also helps establish ordinary high water levels for lakes. This sampling program in particular looks for signs of damage to lakes from urbanization, waste water effluent, and polluted runoff. Since 1976, the MCWD has collected water quality samples from six stations in Lake Minnetonka. These are sampled three times a year. Once a year the MC^ samples 15 lakes upstream from Lake Minnetonka. Three times a year the MCWD coUects samples from eight lakes in the Minneapolis Chain of Lakes, ^boratory analj^is looks at these samples for 15 parameters including nutrients and various chemicals that show degraded water quality. Stream Sampling Streams are important recreational areas and provide important habitat for fish and wildlife. They also deliver polluted runoff to lakes. Stream water quality and quantity data help identify potential flooding problems and gauge degradation to water resources. The MCWD samples ten stream sites twice a year (mid-May and Mid-October). Cooperative Efforts The MCWD has cooperated with other agencies on several data gathering efforts. Oyer the 25 year history of the District’s hydrologic monitoring program, many other agencies