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FINANCIAL STATEMENT The $220,000 required for the project is available in Fund 518 to cover the cost of the proposed project change order. When the project is complete and is recommended for City Council acceptance, a complete reconciliation of the total project costs will be included in the Agenda Report. BACKGROUND Debris in the recycled water distribution system has been a problem at the Ken Mercer Sports Park and the Tennis and Community Park since the parks converted from potable water irrigation to recycled water irrigation. The debris is clogging the 400 micron (1 micron = 1 millionth of a meter) filters housed within the irrigation spray heads which is causing poor or no spray. The law requires that recycled water irrigation systems run at night, so often times dying grass in the 50-foot radius around the irrigation head is the first sign of the blockage. In order to correct a clogged filter, the affected irrigation head must be excavated, disassembled, cleaned, reassembled, installed, and finally tested. This process takes one hour per affected sprinkler head. Between the Ken Mercer Sports Park and the Tennis and Community Park, there are 1 ,812 irrigation heads subject to blockage in the system. Review of recycled water customers in Hacienda Business Park revealed they are not having similar blockage problems, but every one of the customer irrigation systems that were reviewed include a Wye-Strainer filter immediately downstream of the irrigation meter. As installed, all irrigation supplied to the customer passes through the customer's Wye-Strainer filter before being distributed to their landscape irrigation system. Based upon these findings, staff designed a project to install similar Wye-Strainer filters at all seven water meter locations serving the Sports Park and the Tennis and Community Park. The Wye-Strainers look like a backflow prevention device which is common to the potable water system. The filters include a large basket strainer that will catch particles 400 microns or larger, which is the same as the filters in all 1,812 irrigation heads. Cleaning each Wye-Strainer is a relatively simple process, as they are designed for quick disassembly. The Wye-Strainer installation locations were carefully determined by Engineering, Parks Maintenance and Utility Operation staff so as to not interfere with park operations and maintenance, while at the same time being readily accessible for cleaning. Each Wye-Strainer will be covered by a freeze protection blanket similar to those used on potable water back flow preventers. The attachment shows a cross- sectional view of a typical Wye-Strainer and the dimensions that will be above ground for the varying pipe sizes. DISCUSSION Upon completion of the plans and specifications for the project, staff asked GSE, the low bid contractor that was awarded the project to install the recycled water pressure booster station at the Sports Park, whether they would be interested in performing the needed work as change order to the project. A change order is considered appropriate because the piping reconfiguration work to install the booster station is similar in nature to the piping work necessary to install the Wye-Strainers. A change order is feasible because the contract to install the pressure booster station is still open and all bonds and insurances are in place. The benefit to the City of doing the work through a change order on the existing contract is that GSE is able to begin the work immediately and Page 2 of 3