Crane Flat Water System Replacement Phase 2
Phase 1 was completed in the summer of 2010. Phase 1 installed new 6 and 8 inch water mains under the Crane Flat Campground roads and new service lines to the five campground comfort stations. Phase 1 also installed an 8 inch water main under Big Oak Flat Road to the Tioga Road intersection, near the gas station.
This Phase 2 will continue from the intersection of Big Oak Flat Road and Tioga Road with the installation of a 10 inch water main under Tioga Road to the existing 50,000 gallon water storage tank. Phase 2 will also provide new water service lines to the gas station, ranger residence duplex, ranger station, and Yosemite Institute Campus. This replacement system will provide approximate 1,300 gallons per minute (gpm) of fire flow protection at the Crane Flat Gas Station. If project funding allows, a 1,000 foot deep test well will be drilled near the existing well OW-1, just off the trail going to Tuolumne Grove. A groundwater consultant studied the Crane Flat area in June, 2011 on the feasibility of drilling a deep hard rock well. This study recommended drilling to at least 1,000 feet in the area near Well OW-1. If this test well is capable of producing 10 to 15 gpm, the park will consider this as a future water source for the Crane Flat area, thus abandoning the existing source, Doghouse Meadow Well.
A Value Analysis on the replacement of the Crane Flat water system was conducted on January 6, 2009. Because the existing alignments are crossing sensitive natural resources (wetlands and wilderness area), it was decided to reroute the new alignment out of the wetlands and wilderness area to previously disturbed roadways, thus improving efficiency in operating and maintaining the system. This will allow the slurry-fill abandonment of the existing water mains that are in wetland/meadow areas so the piping does not act as conduits, thus disrupting the natural flow of water in the wetlands/meadows. Slurry-filling provides a cost savings when compared to the removal of abandoned lines and digging up the meadows/wilderness. It was also decided the existing water lines within the roadways would be abandoned in place, with the exception of lines crossing wetland areas being slurry-filled. This also provides a cost savings by not having to excavate and repave roadways.