The Joint Transmission Main (JTM) is a 60-inch water pipeline that was constructed in 1961 to convey potable water from a Metropolitan Water District (MWD) connection in Irvine, California to Bradt Reservoir and Schlegel Reservoir in San Clemente, California. Collectively, these facilities comprise the Joint Regional Water Supply System (JRWSS), a section of which is contract operated by South Coast Water District ("District''). The District plans to install or improve cathodic protection equipment at 26 locations within JTM easement along approximately 6. 2 miles of the pipeline route. Improvements to the cathodic protection system would be completed at existing manways, vaults, air-vacs, or similar pipeline access locations. All project work would be within a 20-foot JTM easement. Six of the work locations are at "off-road" sites (Figure 1) and the remaining 20 sites are within or adjacent to paved roads in urban areas (Figure 2).
Project work at each of the JTM cathodic protection system locations would generally be confined to a small work area of approximately BxB feet. Some locations will require an excavation to a depth of 6 to 1 O feet and may require a somewhat larger work area. When completed, the surface equipment would be similar to the existing features. Construction is expected to take approximately four months, however work at any individual site would generally require only one to five days. Some locations along the JTM easement have become overgrown and may require vegetation removal within the work area. No trees would be removed for construction.