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The $8 million project was funded in part by $1.6 million in federal and state funds obtained through the district's participation in the NBWRP. The facility utilizes ultrafil- tration and UV disinfection to produce up to 0.7 MGD of tertiary recycled water with full redundancy. LGVSD partnered with another NBWRP member, the North Marin Water District (NMWD), to distribute the recycled water to customers to the north of the facility. NMWD distributes the water throughout its service area to schools, parks, and commercial landscape users. LGVSD designed the facility to be expandable up to 5.4 MGD, which can be accomplished by simply installing addi- tional filtration units, according to District General Manager Mark Williams. The recycled water facility includes two ZENON ZeeWeed 1500 ultrafiltration membrane units, with current capacity of 0.7 MGD each, but can be expanded to 1.35 MGD. The two Trojan UVFit ultraviolet disinfection system units each have a capacity of 1.8 MGD. "We started with a small plant, but as we worked through the design process, our board and staff recognized the importance of having it readily expandable," he said. "One of the unique features is our ability to add plug and play filtration units that come on a skid." Williams also noted that the ultrafiltration and UV disinfection treatment technologies provide the first step in a direct or indirect potable reuse process. "We selected this technology in anticipation of potable reuse, should it become a treatment option as the first step in that process," he said. The Napa Sanitation District (NSD) has leveraged its participation in the NBWRP to fund a portion of its expanded recycled water facility. The district produces about 2,200 AFY of tertiary quality recycled water that it distributes to nearby customers for irrigation of golf courses, industrial and commercial landscaping, schools, and parks. The NSD also uses recycled water on its own property to raise fodder crops. All of the wastewater at the NSD plant receives second- ary treatment, utilizing both activated sludge and pond treatment methods. For the tertiary quality recycled water, the NSD expanded its capacity by adding additional Dynasand continuous backwash sand filters to its existing system. After going through the sand filter treatment, the recycled water receives extended chlorination. The facil- ity is designed with the capability of adding additional components as demand for recycled water increases. To date, the NSD has spent $15.3 million on the project and received $2.1 million federal and state funding. It antici- pates additional federal grant funding for the project. Storage Is A Key Component Because demand for recycled water is greatest during the dry summer months, storage during off-peak months is a critical component of any water reuse program. In Phase 1, the Sonoma Valley County Sanitation District completed a reservoir storage project that provides storage of up to 100 acre-feet of water that can be used on a year-round basis by grape growers. The Sonoma Valley system also includes two large storage reservoirs, with a capacity of 355 acre-feet, that can be used for vineyard irrigation, and it also provides water for habitat enhancement for wildlife, including a variety of waterfowl and other birds. The NBWRP's next phase will include a greater empha- sis on storage, with as many as 18 storage projects in the planning stages, including projects that will again integrate multiple benefits into their design. For example, a storage pond could provide habitat enhancement for wildlife, protection against sea-level rise, assist with groundwater recharge, and provide community recreation and open space. Recycled water is distributed to a variety of locations in the program area for a variety of uses. The Novato Sanitary District and the Las Gallinas Valley Sanitary District treatment facilities both provide water to the North Marin Water District, where it is distributed to its customers for irrigation landscaping, parks, playgrounds, and a golf course. Environmental Benefits For Fish And Wildlife The NBWRP has gone beyond the traditional uses for recycled water by including a significant habitat restora- tion project: the Napa-Sonoma Marsh Restoration Project. This is a multiagency effort, involving the Sonoma County Water Agency, Sonoma Valley County Sanitation District, California Department of Fish and Wildlife, the Army Corps of Engineers, the state Coastal Conservancy, and federal Bureau of Reclamation. Recycled water from the Sonoma Valley County Sanitation District will be used to dilute a 300-acre pond that was formerly used to produce salt. The highly saline contents of the pond could, if left in its current condition, harm fish and wildlife if a storm or flood breached the levees surrounding the pond. By dilut- ing the contents of the pond with fresh recycled water, the salty mixture can be slowly released into the nearby San Pablo Bay. The Napa-Sonoma Marsh Restoration Project, which is expected to take up to 10 years to complete, has addi- tional environmental benefits. The NBWRP provided the 3.5-mile pipeline that carries water to the salt pond. The pipeline travels through the Carneros wine-growing region, a notoriously dry region where the groundwater basin is under pressure from urban development and agriculture. Studies have indicated groundwater levels are dropping, and there is the threat of seawater intrusion. Grape growers along the pipeline route now have access to the recycled water for vineyard irrigation, decreasing pressure on groundwater and allowing much higher yields for the world-class vineyards. Vineyards in the Carneros region are farmed with very little water, and yields are typically about one ton to the acre. With abundant water for irrigation, those yields could triple or quadruple, providing additional economic benefits to the region. Water Reuse wateronline.com ■ Water Online The Magazine 40 3 8 _ V E R T _ 0 2 1 4 E Z i n e _ M B W R P _ D G . i n d d 2 38_VERT_0214 EZine_MBWRP_DG.indd 2 1 / 3 1 / 2 0 1 4 1 : 2 1 : 1 9 P M 1/31/2014 1:21:19 PM