4.3.1 The contractor must comply with all current cross connection and back flow requirements if job requires a new back flow prevention device. It is the contractor’s responsibility to coordinate with the City's Water Department for the type of back flow prevention as required on the specific job and to obtain permits if this is to be a new installation. The City will be responsible for coordinating the installation of any new water meters. 4.3.2 Any installation of new PVC piping, other than that for repair of an existing pipe, must be installed with the following depth requirements by its specific purpose: a) Main Pressurized Pipe – 18 inch depth of cover. b) Lateral or Zone Pipe – 12-inch depth of cover ¾ inch – 1 inch pipe 18-inch depth of cover for 1 ¼ inch pipe and above c) Conduits used for Electrical – 24-inch depth of cover. 4.3.3 Installation of under pavement sleeves for irrigation pipes or wires must be a minimum of 12 inches below lowest point of aggregate used for asphaltic base or 12 inches below the bottom of concrete used for walks or drives. The diameter of the sleeve shall be a minimum size that is twice the diameter of the pipe to be sleeved. The sleeves shall be double in size if two (2) pipes are used. The sleeves may be used to conduit electrical control wires as well. Minimum sleeve sized for wires shall be two (2”) inches. Example: 1 ½ PVC = 3 inch sleeve 2" PVC = 4 inch sleeve 2 each 1 ½ PVC = 6 inch sleeve 4.3.4 If the installation of underground direct burial wire is installed in a trench containing PVC pipe, the wire will be placed under the PVC pipe. 4.3.5 Backfilling of trenches containing pipe or wires shall be re-compacted with a vibratory packer machine to minimize future sagging of ditch and to prevent liabilities from unseen depressed areas. Backfill material shall be free of sharp objects or rocks to prevent damage to pipe or wires during recompaction. 4.3.6 Backfill material surrounding sprinkler heads shall be a permeable sand or light pea gravel to discourage puddling around sprinkler head. Sprinkler heads shall be installed to the proper grade and shall be hand compacted only.
