2016-01-26_PWETC_AgendaPacket - Laserfiche WebLink

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Attachment C City of Roseville Public Works Department The Roseville Public Works Department saved money, reduced application rates and improved our level of service with several major changes: plowed more, anti -iced, increased prewet rates and modified our brine. These changes translate to application rate reductions of 100-200 pounds per lane mile. We base our salting decisions on a detailed snow policy that specifically calls out our duty to provide "safe winter driving conditions," not to provide bare pavement. Also, all of our winter operators have been through the MPCA training. Even operators who might not consider, themselves environmentalists now know the benefits of less salt and are committed to this goal. One of our best tools for anti -icing is a spreadsheet. We have recorded all our anti -icing application we've made. We note the forecast, pavement temps, application rate, material used, and then note the effectiveness. We can understand when anti -icing will be helpful and when it is not. Based on this, we have created a guide with a series of questions that help us decide whether or not to anti -ice. Our anti -icing program now covers over 60 lane miles when conditions are appropriate. In 2008 after attending an MPCA winter maintenance class we built a small walk behind brine applicator from an old Earthway spreader. A 5 gal bucket was the tank and a 4' section of PVC was the spray bar. We treated City Hall sidewalks for the season and quickly realized it could lead to reduced salt use. The next year we bought a 275 gal tote tank and rigged up a system on 3/4 ton pickup. We could only do about 12 lane miles and had to drive very slowly to maintain our desired application rate. Equipment upgrades over the next 7 years have allowed us to apply the correct rate at traffic speed, and within a single day. We have incorporated brine and Ice Bite 55 into our deicing. We increased the amount of brine applied at the spinner for deicing, and incorporated Ice Bite 55 brine mixtures into both pre -wet and anti -icing operations. Most of our trucks had only a very small, fan nozzle for pre -wetting. After attending the MPCA class, we checked how much brine was actually coming out. It was only 2 gal per ton, likely leading to many of our seasoned veterans doubts about pre -wetting. We pulled out all the nozzles and let the quarter -inch hose spray directly onto the salt. This gets us closer to 10-15 gal per ton. We've switched to purchasing our plow trucks with hydraulic brine pumps that can be calibrated. With higher brine pre -wet application rates we've noticed a much greater effect on our spread pattern and bounce. Our drivers make sure Leave the garage with fully loaded tanks. We've been blending salt brine with Ice Bite 55. First of all, it is both cost and space effective. We do not have the space for a brine making system. We put up a large pallet rack that holds 4 tote tanks at a time and 'one on the floor. This is plumbed to a large pump with 2" hoses. We fill totes with salt brine from the county, and then blend it with Ice Bite 55 in house. We blend it 90/10 for anti -icing, greatly improving adhesion to the road surface. For pre -wet, we blend it around 75/25 or 70/30. Our goal in winter is simple, continue to earn and exceed our reputation for exceptional winter road maintenance without significant cost to tax payers or the environment.