CITY OF BEVERLY HILLS PUBLIC WORKS DEPARTMENT MEMORANDUM. Gil Borboa, P.E., Assistant Director of Public Works/Utilities

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1 CITY OF BEVERLY HILLS PUBLIC WORKS DEPARTMENT MEMORANDUM TO: FROM: DATE: Public Works Commission Gil Borboa, P.E., Assistant Director of Public Works/Utilities February 14, 2019 SUBJECT: Emergency Water Storage Evaluation Update & Review Fire Safety ATTACHMENTS: 1. Emergency Storage Evaluation, Hazen & Sawyer 2. Reservoir/Pumping Station Fire Safety Review RECOMMENDATION This report is for information only. BACKGROUND The recent interruption of service resulting from a leak in the MWD Santa Monica Feeder (December 2018), which currently provides 100% of the water supply for the City of Beverly Hills, underscored the importance of local water storage in emergency response scenarios, including planned and unplanned interruptions in deliveries from MWD. Furthermore, the experiences of other California communities in response to recent wildfires emphasized the significance of fire preparedness of a community distribution system s water storage, pumping, and delivery systems. The City of Beverly Hills maintains a total volume of 43 Million Gallons (MG) of potable water storage in 10 reservoirs throughout the city to provide operational, fire, and emergency storage. The reservoirs are located at various elevations to serve different pressure zones. Water is moved throughout the system to higher or lower zones utilizing booster pumps to lift water to higher zones or pressure reducing valves to move water to lower zones. Diesel backup engines are available at all booster stations to provide emergency service in the event of an interruption in the Southern California Edison power grid. Table 1 below provides a summary of the City s currently available storage.

2 - Table I Storage Reservoir Summary RESERVOIR ZONE SERVED CAPACITY(MG) B A Greystone A Woodland Coldwater Sunset T TOTAL 43 MG On December 4, 2014, the Public Works Commission was presented an Emergency Storage evaluation prepared by Psomas. The Psomas 2014 evaluation is presented as Attachment 1 to this report. (The 2014 study was also included as an Attachment to the January 2019 Integrated Water Resources Master Plan agenda report; it is included here for ease of reference.) - On January 24, 2019, Public Works staff and Beverly Hills Fire Department staff conducted site visits to reservoirs with adjacent Booster stations to assess fire safety conditions. This review comprised visits to reservoirs north of Sunset Boulevard: Greystone, 4B, 5, 6, 8, 3A, and Woodland. DISCUSSION Under current conditions, without the use of local groundwater supplies, the City must rely on water in storage in the event the MWD supply becomes unavailable as in the December 2018 event. According to protocol for such events, the City was able to utilize an interconnection with the City of Los Angeles for continuation of supply, but not until after the city experienced a 24-hour period of complete self-reliance utilizing only water stored in City reservoirs. Forecasting to an event (e.g., earthquake) in which interconnections with MWD and Los Angeles are interrupted, an evaluation of days of available storage in City reservoirs may prove valuable for emergency planning and future capital improvement project planning. The following section from the Metropolitan Water District Administrative Code addresses the storage required of each MWD member agency. A minimum of seven days storage 2 of 6

3 is required as highlighted in section 4503 of the MWD Administrative Code below. Highlighting added in the section addressing Suspension of Deliveries. (a) Whenever repairs or maintenance of the District s system, in the opinion of the General Manager of the District, shall require suspension of delivery of water at any point or points, such delivery may be suspended without liability on the part of the District; pro vided, that except in cases of emergency, as determined by the General Manager, notice of such suspension of service shall be given to the affected member public agency in advance of such suspension. Metropolitan will make a concerted effort to notify and work with member public agencies regarding all scheduled interruptions. The District will schedule non-emergency interruptions for the low demand months of the year, typically October through April, in coordination with the member public agencies. (b) Each member agency shall have sufficient resources such as local reservoir storage, groundwater production capacity, system interconnections or alternate supply source to sustain: (1) A seven-day interruption in Metropolitan deliveries from raw and treated water distribution facilities based on average annual demands of the affected facility. (2) For service connections installed or modified after December 37, 2008 on raw water conveyance facilities, a seven-to twenty-one-day interruption in Metropolitan raw water deliveries based on average annual demand of the affected facility. The current update to the assessment of emergency storage is included with this report as Attachment 1. The study was conducted by Hazen and Sawyer (H&S), within the purview of the Integrated Water Resources Master Plan (IWRMP) currently underway. Whereas the 2014 study used system demand data from the 2002 Water Master plan and the 2010 Urban Water Management Plan, the current study used demand data developed for the recent cost of service study, taken from calendar year 2017 Automatic Meter Infrastructure records. A summary of available days of emergency storage, at various stages of conservation in the event of an emergency, and at various stages of completion of the city s water production/treatment capacity, is provided in Table 2 below: 3 of 6

4 Table 2 Emergency Storage Summary 2019 Peak Demand (Current Day, WTP offline 2020 Peak Demand (WTP design build complete) 2022 Peak Demand (WTP design build complete) Although the comparison of the resulting Emergency Supply results against the prior 2014 study may not fundamentally be the same, the significant point to be made in the current analysis is that the increase in calculated Emergency Supply days for 2019 results principally from the reduction in demand as a result of the State-mandated conservation efforts of 2015, and the ongoing City efforts to maintain the conservation levels achieved at that time. ADDITIONAL STORAGE CONSIDERATIONS The City s current focus remains the enhancement and re-deployment of the Foothill WaterTreatment Plant and the full development of the Hollywood, Maple, and La Cienega wells. The renewable capacity afforded by local groundwater production not only increases the number of days of available emergency storage duration, but also meets the criteria stipulated in the MWD Administrative Code for components of a member agency s emergency storage capacity. An additional component included in the MWD Code are system interconnections, of which Beverly Hills maintains three with Los Angeles: Woodland Reservoir, Reservoir 7, and Zone 9 interties. As stated in the Emergency Storage Evaluation, development of additional storage presents challenges including land acquisition, hydraulic continuity, and construction 4 of 6

5 impacts. Additionally, significant funding may be required. Nevertheless, among properties for which the Water Enterprise Fund retains ownership, three sites may warrant further consideration for development of additional storage. At Cabrillo Reservoir (constructed 191$, retrofitted 1927), recent structural assessments indicated inadequate safety factors against sliding/overturning in an earthquake event, and seepage into the tank of local surface water and shallow groundwater. The facility is useable only for nonpotable water after the placement of a liner in recent years. At reservoir 4B, an adjacent pad was created on which to construct a second reservoir, however, the structural properties of the soil under the pad were found to be insufficient to support a full reservoir. In 2018, the city purchased a residential property at 1297 Monte Cielo Drive with future consideration for a water storage facility. All of these sites remain as potential future locations for additional reservoir locations, with potentially an estimated total combined capacity of 3 million gallons. A more detailed analysis and recommendations for future development of additional water storage will be addressed in the IWRMP. RESERVOIR/BOOSTER STATION FIRE SAFETY REVIEW Recent wildfires throughout California accentuate the importance of maintaining the ability to provide water for fire-fighting and structure protection. As experienced in the Woolsey Fire in Los Angeles County, significant loss of property resulted in part from the inability to maintain service at the water utility s booster stations required to move water throughout the area. On January 24, 2019, staff from Beverly Hills Fire Department joined Public Works staff to review reservoir sites north of Sunset Boulevard at which booster stations are located. At each location, the booster station typically comprises a series of pumps powered principally from the Southern California Edison (SCE) grid, with a backup diesel engine and diesel fuel storage available in the event of a loss of SCE service. The focus of the site visits was to review the fire preparedness of the reservoirs/pump stations. BHFD personnel were able to identify some fuel modification action items that would enhance the survivability during a strong wind driven fire. The common approach to the recommendations provided by BHFD addressed the removal of fuel (brush, trees, vegetation) around the periphery of the reservoirs and/or booster pumps. The pump stations reviewed are listed below in Table 3. Notes and photographs are included in Attachment 2. Public works staff including Water Operations and Urban Forest personnel will coordinate and plan the appropriate brush clearance and tree trimming at the sites to address Fire Department recommendations. Regular maintenance will be scheduled to provide continuing fire safety preparedness. 5 of 6

6 Table 3 Reservoirs! Booster Station Fire Safety Review Locations Reservoir/Booster Station Greystone 4B Monte Cielo/3A Woodland 6 of 6