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2009 Annual Report | Public Works Department Page 3 Buildings & Grounds - maintain and repair buildings and grounds 100,000+ square foot building operated/maintained 5+ acres grounds maintained Vehicles & Equipment - maintain and repair vehicles and equipment 55+ City owned vehicles and heavy/highway equipment, including: 35+ cars/trucks maintained 3 plow trucks/1 water truck maintained 1 loader/1 backhoe/1 compactor maintained Other Noteworthy O&M Repair Activities: New Year’s Eve 2009 Water Main Break Sometime between 4:00 and 4:30 the afternoon of December 31, 2009, a 10-inch water main broke in the south boulevard of County Road I near the Caribou Coffee/Little Caesar’s Pizza entrance to Mounds View Square Mall. Temperatures were subzero or hovering around zero degrees most of the day. At 5:00 when PW maintenance staff arrived at the scene, a torrent of water was running down all lanes of County Road I much like a swollen creek or small river. It was also around this time that residents were noticing very low water pressure city-wide, a result of the nearby 500,000 gallon water tower being drained empty and the 2 million gallon ground reservoir half-full. PW maintenance staff worked quickly to restore water pressure by starting several additional pumps to get the water tower and reservoirs filled up. At the same time, PW staff isolated the water main break by closing gate valves. Normal water pressure was restored around 7:00 that night. However, a 7-foot deep, 10-foot wide, 15-foot long cavern-hole was the end result of approximately 1.2 million gallons discharging through the break. The City’s water service contractor, Dave Perkins Contracting, was called the next morning (New Year’s Day) to perform the repair due to the need for heavier equipment required to cope with the frozen ground and exposed underground utilities. The break was repaired at about 1:30 in the afternoon and water service was restored to Mounds View Square shortly thereafter. cavern/hole left from water main break (before repair) contractor performing repair activities Chemical Scales and Chemical Switch-Over Units PW maintenance staff replaced the failing water treatment plant original equipment used to feed chemicals to treat the raw ground water to drinking water standards as part of the treatment process. Booster Station Structural Floor Repair The structural concrete floor in the booster station had been settling for many years and supports for the dual 12-inch water pipes are supported by the floor, resulting in inadequate support of the pipe. PW staff contracted with A-1 Mudjacking to restore the floor to near its original elevation.