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A WDODARR &CURRAN Mossdale, Central Lathrop, and River Islands development areas. The permitted capacity is limited by recycled water storage and disposal capacity(currently 1.69 MGD ADWF). The Lathrop CTF is permitted for a maximum capacity of up to 6.0 MGD with additional expansions. The City has the ability to further upgrade the Lathrop CTF to increase the treatment capacity up to 9.0 MGD as needed.6 Wastewater treatment and disposal at the City's Lathrop CTF is regulated under Waste Discharge Requirements (WDR) Order No. R5-2016-0028. Because the Lathrop CTF applies treated effluent to land, it is not subject to the National Pollution Discharge Elimination System(NPDES) requirements for discharges to surface water.?Wastewater treatment processes at the Lathrop CTF include secondary treatment,tertiary filtration,and disinfection prior to storage and disposal. The Lathrop CTF produces disinfected tertiary recycled water suitable for irrigation at parks, landscape strips, median islands, pond berms, and agricultural fields. The City has constructed and is operating a 10-acre percolation basin at former land application site, LAS-3, located northeast of the Lathrop CTF for the disposal of 0.3 MGD of tertiary treated effluent. For this, the City prepared a comprehensive analysis of percolation basins for groundwater recharge in Percolation Disposal Capacity Evaluation (Stantec, 2014). In addition, a recent study of the percolation capacity at the former LAS-3 supported an increase in capacity from 330,000 gallons per day(gpd)to 361,000 gpd and was approved in September 2019. 2.1.3.3 Recycled Water Use and Distribution The recycled water distribution system conveys tertiary effluent from a storage pond at the Lathrop CTF to lined storage ponds and agricultural land application areas throughout the City.The system consists of approximately 113,000 linear feet of recycled water piping infrastructure and four booster pump stations. The pond parcels total 52 acres, with a combined capacity of approximately 139 million gallons. These distributed storage ponds are used to store recycled water during low irrigation demand periods (i.e., winter)for use during high irrigation demand periods (i.e., summer). The storage ponds and agricultural land application areas are located in the East Lathrop, Mossdale Landing East,and River Islands areas. During 2015, the City recycled 429 AFY of tertiary effluent, which was applied to agricultural irrigation. In the near-term, the City plans to continue agricultural land applications and construct additional storage and percolation ponds and agricultural sprayfields as the City's wastewater flow to the Lathrop CTF increases. Consistent with the City's 2015 UWMP, projected recycled water used for agricultural irrigation is estimated to be equal to the volume of treated effluent available.As stated in the 2015 UWMP, agricultural land application remains as the primary recycling method for the City's tertiary effluent. For the longer term, the City is developing a recycled water implementation plan that will support the use of recycled water to irrigate public landscaping. All major new City developments (Mossdale, Central Lathrop, and River Islands) are connected to the recycled water system to enable the future use of recycled water for public landscape areas. These landscaping areas include existing and planned, parks and playgrounds, schoolyards, roadway medians, commercial landscaping, and open space. 2.1.4 Other Non-Potable Supplies In addition to the City's anticipated recycled water supplies, River Islands has constructed a municipal irrigation system which utilizes City recycled water to supply the needs of the public landscape areas.When City recycled water supply is low or unavailable, lake water(a combination of stormwater and native groundwater)is utilized to meet non-potable 6 The City previously completed a project-level Environmental Impact Report(EIR)for treatment capacity up to 6.0 MGD at the CTF.Post combination with Crossroads WWTF,the program-level EIR treatment capacity at the CTF has increased to 9.0 MGD. 7 However,the City is currently pursuing a surface water discharge permit. Califia(0011533.00) 21 Woodard&Curran, Inc. River Islands Phase 2 Development Water Supply Assessment September 2020