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FINAL DRAFT PRELIMINARY REPORT (Connections to EOCF #2) In summary, the above proposed improvements can provide up to 3 to 4 cfs excess groundwater to South Orange County. The City of Tustin will benefit from the new well and the upgrade of the RO Treatment facilities for the wells at the Main Plant. 5. PROPOSED CONVEYANCE FACILITIES 5.1 Identification of Conveyance Options The proposed conveyance facilities consist of the following: new high pressure discharge piping from the proposed pump station to the connection to the East Orange County Feeder No. 2; pressure reducing facility to allow high pressure water to be relieved back into the City's distribution system; and connection to the East Orange County Feeder No. 2 existing piping facilities (between the meter vault and the MWD connection vault). The general criteria for the identification of conveyance options was to locate the new high pressure discharge piping within public streets and to minimize the length of piping within major arterial streets. Below is a summary of the preliminary conveyance options that were identified for each of the above possible locations for the proposed EOCF#2 Pump Stations. 5.2 Typical Connection to the East Orange County Feeder No. 2 The typical connection to the East Orange County Feeder No. 2 consist of the following: pressure reducing vault and corresponding piping that allows for the manual discharge of the high pressure excess groundwater back into the City's distribution system; additional manual valves to keep the excess groundwater from flowing through the existing meter in the meter vault; new flow control meter vault; new connection to the existing piping between the MWD connection vault and the meter vault. For this study, we have assumed the layout of the proposed new flow control meter vault will be similar to the IRWD Interconnection to SOC Water Transmission Mains, Phase A JTM/ATM Connection. The proposed flow control facility will include: magnetic flowmeter; modulating butterfly valve; blind transmitters and pressure gages; meter test tap; precast concrete vault; double door aluminum vault hatch; forced ventilation; sump pump; and corresponding electrical and controls. Typical sketches of the proposed facilities are included in Appendix C. 5.3 City of Santa Ana East Station Facility Figure 1 shows the facility location and the corresponding proposed conveyance piping. The following is the proposed alignment: St. Andrews Place to S. Grand Ave. to St. Gertrude Pl. to S Lyon St. to Richey Street to City of Santa Ana's SA-7 Pressure Regulating Station. Assuming 14 cfs excess groundwater, the EOCF#2 Discharge Water Main is proposed to be 24-inches in diameter and rated for 200 psi. The pressure reducing facility can be located within the SA-7 Pressure Regulating Station and can connect to both the Lower Zone distribution piping as well to the existing City of Santa Ana 24-inch high pressure water main that goes to the existing SA-7 MWD service connection. Figure 2 shows the proposed MWD connection facilities at Warner Ave. and Red Hill Ave. These proposed facilities will include: connection to the existing City of Santa Ana 24-inch piping upstream of the existing SA-7 meter vault including a new 24-inch valve; proposed meter flow control vault with 24-inch modulating butterfly valve and magnetic flow meter; connection to the existing 24-inch piping between the meter vault and connection vault, including two 24-inch valves (one on the downstream side of the flow control vault and one between the connection and the existing SA-7 meter vault; and new electrical and SCADA control facilities. The proposed flow control vault is recommended to be located in the existing public parkway right-of-way or within an easement adjacent to the parkway. If not feasible or easement is difficult to obtain, it could be located within the street if there is open utility corridor. Orange 9tq%9 1District/Moulton Niguel Water District 30 - 25 5/17/2 A TECH Evaluation of Groundwater Conveyance Options 13