Ramsey Resident - 2012 - November/December

Home

Salt and Ice Control ăJTBSUJDMFXJMMIPQFGVMMZanswer some of the questions people have about ice control and what methods we use UPQSPWJEFUSBDUJPOJOPVSDPNNVOJUZ5PTUBSUPVUXFđSTUNVTUIBWFTPNFCBTJDLOPXMFEHFPGUIFNBUFSJBMTVTFEJO the process. Sand on its own does not have ice-melting capability. Sand is primarily used as an abrasive to provide tempo- rary traction. Sand works best on hard packed snow where it can embed itself into the snow and remain there. When used on ice, sand has a tendency to "bounce" when it comes out of the truck and end up at the side of the road. We use a salt/sand mixture of approximately 15% salt and 85% sandăFTBMUQSFWFOUTUIFTBOEGSPNGSFF[JOHJOUIF pile and provides some ice-melting capability to the mixture. We still use some sand/salt, but because of its temporary nature, only in extreme cold weather or freezing rain. Many of the larger cities and highway departments are reassessing their use of sand in their snow and ice control programs. Several reasons given were the cost of clean-up, the clogging of storm sewer inlets and the rising concern PWFSBJSQPMMVUJPO8IFOUIFTBOEJTESJWFOPOCZUSBċDUIFTBOEJTDSVTIFEJOUPTNBMMFSQBSUJDMFTBOEEJTUSJCVUFE JOUPUIFBJSXIFSFJUIBTBOFHBUJWFFĈFDUPOBJSRVBMJUZ Pure salt is used on all of our primary roads and intersections to help control ice. Salt has a practical working temperature of 15 to 20 degrees F. What this means is that water normally freezes at 32 degrees, but with the introduction of salt the freezing temperature is lowered to the 15 to 20 degree SBOHFăFTVSGBDFUFNQFSBUVSFPGUIFSPBEEFUFSNJOFTUIFBNPVOUPGEFJDJOHDIFNJDBMOFFEFEBOE IPXFĈFDUJWFMZUIFDIFNJDBMXJMMXPSL"TUFNQFSBUVSFTHPEPXO UIFBNPVOUPGEFJDFSOFFEFEUP NFMUBHJWFORVBOUJUZPGJDFJODSFBTFTTJHOJđDBOUMZ4BMUJTđWFUJNFTNPSFFĈFDUJWFBUEFHSFFTUIBOBU 20 degrees. Before a dry de-icing chemical can act it must dissolve into a brine solution. Brine is the term VTFEUPEFTDSJCFUIFTBMUBOEXBUFSNJYUVSFăFOFDFTTBSZNPJTUVSFOFFEFEUPBDDPNQMJTIUIJTDBO come from snow on the road surface or from water vapor in the air (humidity)...to create this moisture SFRVJSFTIFBU4PVSDFTGPSUIJTIFBUXPVMEJODMVEFUIFBJS UIFTVO UIFQBWFNFOU PSUSBċDGSJDUJPO"U extremely low temperatures many of these sources are not available. .BOZDPNNVOJUJFTBSFOPXQSFXFUUJOHUIFJSTBMUăJTJTBDDPNQMJTIFECZQMBDJOHBCSJOFUBOL POUIFSFBSPGUIFTBOEJOHUSVDLUPXFUUIFTBMUXIFOJUDPNFTPĈUIFTQJOOFS8FUUJOHQSPWJEFTNPJT ture to make brine and speeds up the melting process. In addition, the wet salt has less of a tendency UPCPVODFPSCFCMPXOPĈUIFSPBECZUSBċD"OPWFSBMMTBWJOHJOMPTUPSXBTUFETBMUDBOCFBTIJHIBT 20% to 30% with the use of pre-wetting. "OPUIFSDIFNJDBMVTFEUPđHIUJDFPOSPBEXBZTJTNBHOFTJVNDIMPSJEF.BHOFTJVNDIMPSJEFIBT a practical working temperature of -15 to -25 degrees Fahrenheit and is capable of attracting moisture EJSFDUMZGSPNUIFBJS*UJTWFSZBĈFDUJWFBUUFNQFSBUVSFTCFMPX'BOEJTGBTUBDUJOH8FDVSSFOUMZVTFBMJRVJEGPSNPG magnesium chloride to pre-treat our salt in colder temperatures. With over 140 miles of roadway and some 860 intersections we rely on the police department and phone calls from citizens to alert us to problem areas that may appear CFDBVTFPGFYUSFNFMZDPMEUFNQFSBUVSFT5SBċDDBOBMTPDBVTF slippery areas by tracking the salt out of an intersection or by packing down the snow before the salt has a chance to work. 8FEPPVSJOJUJBMTBMUJOHBTXFBSFQMPXJOHUIFSPBETBĕFSB storm and sometimes problem areas occur before we can get back to complete our salting operation. I hope this answers some of the questions about salt and sand and how we use them in our operation. If you have any questions or concerns, please call the Public Works Superin- tendent Grant Riemer at 763-433-9863. November/December 2012 • Ramsey Resident 13