Glacier Point Surface Water Treatment System Replacement

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The existing Glacier Point water system provides approximately 9,000 gallons per day for visitors and employees. It presently operates under a temporary waiver from California Department of Public Health (CDPH) to allow the use treated surface water from Pothole Meadow and Union Point. During 2010, the National Park Service attempted to drill two wells and connect to the existing water system. Both wells resulted in very low gallons per minute yields.

The only remaining viable option for potable water at Glacier Point is surface water and an associated surface water treatment system. The surface water treatment system will consist of filtration and disinfection. Park engineering and operator staff has determined that a 20 feet x 24 feet building will be sufficient to treat water at Glacier Point in the near term and will be sufficient for long term needs provided that future water consumption remains relatively consistent.

The proposed building will be inset into a previously disturbed bank. One 12 inch diameter tree, and not more than three smaller trees, will need to be removed.

The proposed building will be located for minimal visual intrusion. The existing building is not sufficient to meet CDPH requirements for surface water treatment and will be removed when the new treatment system is inaugurated. Associated work outside the building will include trenching and installation of underground pipes, trenching and installation of signal wires, and installation of an underground wastewater storage tank. The 500 gallon tank will be installed to receive wastewater from the treatment system. The wastewater will consist of small amounts of effluent from a small sink and treatment system analyzers. The only surface feature will be a manhole top and cover set six inches above grade level. Pump out frequency is expected to be about once every two months. A French drain will be installed to receive less than 200 gallons per day of raw water after testing.

Automated control will improve treatment system efficiency and reduce waste. In addition, telemetry will be installed to replace otherwise necessary maintenance trips. These 60 mile round trips are circuits including other nearby utility systems. This project will reduce each road trip by 12 miles in the near future and will make 40 mile reductions possible when similar systems are in place elsewhere. Near term and long term monthly travel reductions will be 180 and 400 miles, respectively. Each round trip is made by facilities personnel using trucks. Total disturbed area will be less than 8,000 square feet and will be completely within the 23,000 square feet previously disturbed for water treatment and storage. Within the 8,000 square feet of disturbed area there will be approximately 300 linear feet of trenching and two holes not greater than eight feet in diameter nor more than eight feet in depth.