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installs recycled water piping in Gibraltar Avenue from West Los Positas north to Hacienda Boulevard. The extension will install 4,260 linear feet of pipeline in total, including 3,800 linear feet of 8-inch recycled water main and 460 linear feet of 6- inch recycled main. The proposed Gibraltar Avenue pipeline will serve 12 large commercial irrigation meters. The piping will also be the City's first "looped" recycled water pipeline. The looped feature will provide a secondary feed to the Arroyo Mocho undercrossing from the DSRSD treatment plant. This secondary feed will allow greater water volumes which will help with the demands at the Sports Park and other southern locations in the City of Pleasanton, such as the Koll Center or Callippe Preserve Golf Course. Since the piping in Gibraltar was included in the feasibility study it is included under the CWSRF loan environmental clearances. Ranger Pipelines has agreed to complete the work at contract unit prices, provided they can start prior to demobilizing from the current project. Based on estimated quantities, it is expected this work can be completed for approximately $1,010,000. It is recommended that this work be accomplished with a change order to Ranger Pipelines. 2. The Tassajara Recycled Water Reservoir Valve Vault Improvement work will install an existing refurbished "city supplied" altitude valve and associated piping and valve changes in the reservoir valve vault. When the Tassajara Reservoir was original constructed, potable water flow in and out of the tank was controlled through the use of valve that opened and closed as a result of input provided by a computer program that monitored flow and water pressure throughout the potable water system. Although infrequent, the tank would occasionally over fill and some potable water would be lost with the overflow going into the Tassajara Creek. The proposed altitude valve provides a safeguard that will prevent the overflow of the Tassajara Tank by automatically closing when recycled water flowing into the tank reaches a high water level. The engineers estimate to complete the valve vault work is $65,000. It is also recommended that this work be accomplished with a change order to Ranger Pipeline. 3. The Ken Mercer Sports Park is currently irrigating with recycled water. Before being converted to recycled water, the sports park used potable water at a maximum flow rate of 900 gallons per minute over the course of a 15-plus hour irrigation cycle. Using recycled water requires a shorter watering cycle; starting no earlier than 9:00 pm and ending no later than 6:00 am. To shorten the watering cycle, but still provide adequate water, a flow rate of 1,600 gallons per minute is required. To accomplish this, the irrigation system was divided into sections and additional service connections were added for the new sections. The volume of water can be delivered with the new recycled water system as constructed, but the flow rate results in a pressure drop that causes the sprinkler heads to lose efficiency. The recycled water supply valving located at DSRSD senses the pressure drop, and opens valves to increase pressure to the system thereby restoring pressure at the irrigation heads. However staff has determined that since the water supply valving is located more than a mile away at DSRSD, there is delay in the control of the valves that results in swings between over pressure and under pressure in the entire system. Staff has considered a number of alternatives to Page 6 of 8