This spring, the Ada County Highway District will begin the preventative maintenance treatment of several cul-de-sacs in Maintenance Zone 6 in Ada County. The treatment, called a slurry seal, is very similar to the chip sealing process, which coats the road with a protective sealant and helps prolong the life of the road. Regular chip sealing equipment cannot fit into tight areas such as cul-de-sacs. The slurry seal treatment was designed specifically for the confines and tight turns of a cul-de-sac. Not every cul-de-sac in Maintenance Zone 6 will be treated.