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BACKGROUND The base Pleasanton-DERWA agreement was executed November 2013 with Amendment #1 (maintaining the existing Val Vista Park connection) executed in September 2015. Section 5.3 of the base Pleasanton-DERWA agreement spells out the process and conditions for Pleasanton's recently completed DERWA expansion project, the Sixth Filter, as well as the process and conditions for future facilities expansion project(s) at the DERWA Recycled Water treatment plant. When the base Pleasanton- DERWA agreement was executed, the presumption was that additional treatment capacity would be created by future facilities expansion projects which built more filters in a second, yet to be constructed, filter bank. Unfortunately, although the design capacity of sixth filter targeted a treatment capacity of 1.9 mgd, it was determined after post- construction commissioning and testing this past May that the filter is only performing at a treatment capacity of approximately 1.4 mgd. The poor test performance of the sixth filter brought into the question the wisdom of constructing more filters to meet future targeted RW demands as envisioned by the base Pleasanton-DERWA agreement, as well as bringing to light the fact that the average secondary influent being imported from DSRSD's secondary treatment plant into the DERWA RW plant had a much higher concentration of suspended solids than originally expected, which severely hampered filter performance. To address the filter performance, DSRSD contracted with Carollo Engineers to design the expansion project. In order to boost the existing filters' as well as future yet to be constructed filters' performance to or beyond their intended design capacities, a series of stakeholder meetings including Pleasanton Utilities staff was held, and it was mutually agreed that the planned facility expansion should incorporate a ballasted flocculation process (proprietary name: Actiflow) at the head of the plant, prior to the filtration treatment train. The Actiflow is an industry proven process for removing high volumes of solids from the influent before directing it through the filtration process. With the Actiflow's significant reduction in solids in the pre-filter influent, the treatment capacity performance of the sixth filter (as well as the other filters) will increase from 1.4 mgd to approximately 2.4 mgd. Combined with the other elements of the planned expansion, Pleasanton's share of the DERWA RW production volume will be increased to approximately 4.2 mgd, without the construction of additional filters as envisioned by the original Pleasanton-DERWA base agreement. The other elements, in addition to the Actiflow, of the planned expansion include several pump additions and upgrades, and ultraviolet disinfection enhancements. This expansion project will increase the total plant capacity from the existing 9.7 mgd (net generation of 8 mgd RW) to a potential ultimate capacity of 20.4 mgd. DISCUSSION The purple pipe project is in its completion phase, and as a result, there are still approximately 130 irrigation customers who are in varying stages of permitting their connection to the RW system over the next year. Pleasanton's current share of DERWA RW, as a result of the recently completed Sixth Filter Project, is 1.9 mgd average day flow; however Pleasanton's RW demand forecast is approximately 3.4 mgd average day flow, with occasional peak flows of approximately 4.2 mgd, after the connection of all the remaining RW irrigation customers. Page 2 of 3