15. CONSIDER WATER USE CREDIT FOR INSTALLATION OF SOMAT DISPOSAL SYSTEMS AND WATERLESS URINALS AT THE PRESIDIO OF MONTEREY
Meeting Date: March 15, 2004 Budgeted: N/A
Program/Line Item No.: N/A
Staff Contact: Stephanie Pintar
Cost Estimate: N/A
General Counsel Approval: N/A
Committee Recommendation: The Water Demand Committee unanimously recommended approval of the staff recommendation.
CEQA Compliance: N/A
SUMMARY: The Presidio of Monterey has requested a Water Use Credit of 9.063 acre-feet annually (AF) for replacing water-using urinals with waterless urinals in all publicly accessible areas of the Presidio, and credit of 7.998 AF for retrofitting the garbage disposals in the food service areas with SOMAT disposal systems.
District staff met with the Presidio of Monterey staff in 2001 before the Presidio undertook its plan to retrofit the urinals and the food-service garbage disposals. The purpose of the meeting was to provide guidance to the Presidio on the process for establishing a Water Use Credit. Staff informed the Presidio representatives that as the proposed technology was new, they would need to arrange to have an independent analysis completed of the water savings associated with the proposed retrofits. The independent analysis would be the basis for determining the Water Use Credit.
PMCL (Planning and Management Consultants, Ltd.) of Carbondale, Illinois, prepared an Analysis of Water Use at the Presidio of Monterey (Exhibit 15-A). PMCL will be presenting their analysis to the Board at the March 15, 2004 meeting. Staff has reviewed the analysis and concurs with PMCL’s findings that retrofitting to waterless urinals has saved approximately 9.063 acre-feet annually (AFA) and retrofitting the food service areas with SOMAT systems has saved approximately 7.998 AFA. The savings estimate for the SOMAT systems was adjusted downward following the September 23, 2003 Water Demand Committee meeting, when the Committee asked that the savings be estimated using current flow rates of 2.5 gallons-per-minute, rather than 2.0 gallons-per-minute as used in the PMCL document. Water savings for these retrofits are confirmed by the reduction in metered water use on the Presidio of Monterey, particularly as demonstrated during the winter months when there is no irrigation.
At the November 5, 2003 meeting, the Water Demand Committee asked the Presidio for additional documentation on the number of daily uses of urinals to verify the savings shown in the PMCL report. PMCL prepared a supplementary analysis (Review Of Urinal Savings Calculations For The Presidio) that is attached as Exhibit 15-B. This supplementary document supports PMCL’s original water savings estimate.
It should be noted that the quantification of these savings is based on the comprehensive analysis completed by PMCL specific to the Presidio of Monterey’s unique uses and do not reflect the water savings that could be achieved by installing identical or similar equipment at other locations (i.e., restaurants, hotels, etc.). Individual analyses would be required to quantify savings at other locations.
RECOMMENDATION: Both staff and the Water Demand Committee recommend that the Board approve a Water Use Credit of 9.063 AFA for the retrofit of the Presidio of Monterey’s urinals to waterless urinals and 7.998 AFA for the retrofit of the food service facilities with SOMAT disposal systems. The Presidio of Monterey has provided a sufficient analysis of the water savings associated with the aforementioned retrofits and has met the requirements of the District (as determined by the Water Demand Committee at its May 14, 2003 meeting) to provide evidence of water savings. Directors Edwards, Lehman, Foy and Knight visited the Presidio and observed the retrofits associated with this Water Use Credit request.
BACKGROUND: The following is a summary of the two types of retrofits undertaken by the Presidio of Monterey. In addition to the installation of waterless urinals and the SOMAT disposal systems, the Presidio has also undertaken a number of landscaping retrofits, including replacement of the irrigation system at Soldier Field. In the late 1980’s and early 1990s, the Presidio also initiated and enforced water conservation policies that were in line with the policies of the District’s, including irrigation schedules, water waste restrictions, installation of low-flow showerheads, water-saving toilet retrofits, and public information broadcasts and advertisements about water conservation.
Waterless urinals resemble conventional wall-mounted fixtures. The only real difference is they use no water. A special trap in the bowl contains a floating layer of a lightweight biodegradable liquid. The heavier urine flows through this layer and is completely sealed off from the room atmosphere. Restroom odors are noticeably absent, and toilet surfaces don't breed bacteria. The urinal bowl is pre-coated at the factory with a water repellent protective coating to minimize bacteria growth and solids build up. The walls of the urinal are cleaned periodically like any flushed urinal and three ounces of the special sealant needs to be added to the trap about twice each month. The special trap should be replaced two to four times per year depending on the amount of use, and the waste pipe flushed with about five gallons of water whenever the trap is changed.
Waterless urinals save between one and three gallons-per-use. Urinals designed to meet current water conservation standards use 1.0 gallon-per-flush. Prior to 1990, urinals used 3.0 gallons-per-flush and up. The use of waterless urinals in schools, restaurants, stadiums and other high-traffic commercial and industrial building result in significant water savings. Water savings will vary according to the frequency of use.
The SOMAT pulper grinds and macerates food scraps and disposable dining materials into a water-based slurry that can be pumped to a separate unit for dewatering into a semi-solid portion and a liquid portion. The liquid portion is returned to the pulper for water conservation and minimum discharge into the sanitary waste system. The pulper is coupled with a hydra-extractor, which is a specialized liquid-solid waste separator. The unit uses an electrical helical auger turning inside a cylindrical screen. The unique SOMAT design provides a self-cleaning unit that operates as a continuous processor to separate the waste stream from the SOMAT pulper into its component semi-solid and liquid phases. The SOMAT hydra-extractor does not use rinse water in the cleaning operation.
The SOMAT disposal system is used on every surface ship in the U.S. Navy and is used on over 80 of the world’s cruise ships. SOMAT systems are ideal for the following types of uses: schools, hospitals, colleges, casinos, employee cafeterias, cruise ships and other mass feeding operations.