AgdaPkt 2018-03-26 Joint SA PFA - Laserfiche WebLink

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City of Redwood City Page 31 Sewer System Management Plan, March 2018 Element IV maintenance activities can be completed within the first week of this cycle, leaving two weeks between cycles to complete follow-up maintenance activities and special projects. However, if critical issues are identified that could cause an SSO, these are addressed right away. The City’s lift stations are equipped with Supervisory Control and Data Acquisition (SCADA) control systems. SCADA functionality is observed every morning by both the Utilities Specialist and the Utilities Worker. These staff members carry laptops from which they can access and make changes to SCADA at any time. Otherwise, access to SCADA is limited. City engineers can view the system, but cannot make changes to lift station controls. The City maintains a contract with a SCADA system consultant, who provides regular system support as well as on-call emergency support if needed. Either one or both of the Utilities Specialist and Utilities Worker are on-call 24-hours a day, 7-days a week for emergency response. The City maintains written documentation describing protocols and the application of their SCADA system. IV-6 Lift Station Force Mains and Siphons The City maintains thirty-one (31) separate force mains, one from each lift station. Appendix IV-5 includes the basic force main asset information. Many of the force mains were installed at the time of the original construction of the associated lift station. Force main alignments are inspected annually along with the Lift Station Condition Assessment and documented on the checklist. Discharge points will be surveyed for possible damage and corrosion from the release of hydrogen sulfide when the force mains discharge to the gravity collection system. The City collection system contains twenty-four (24) individual sewer siphons managed and operated by the City staff. Intro Table 4 provides the specific locations and asset information for each of these siphons. Four of the siphons are maintained during high frequency maintenance with the remainder requiring maintenance only upon observation by City staff or the public. IV-7 Lower Lateral Maintenance The City maintains the lower portion of each service lateral from the main line to a property line cleanout by informal operating procedure. The City estimates the total linear feet of City maintained laterals at approximately 575,520 or 107 miles from 18,017 connections. Customers are responsible for installing this cleanout, and the City is not responsible for maintenance of the lower lateral if a property line cleanout is not present. However, if a resident excavates the area at the property line, City sewer crews will cut and access the pipe to perform a CCTV inspection of the City’s lower lateral to verify whether or not there are any deficiencies of the sewer pipe. If it has been determined that there is, City crews will perform a repair of the lower lateral. If not, the City will recommend that the property owner install a property line sewer cleanout to allow the City’s sewer staff to have access to the lower lateral. City staff estimates that approximately 90 percent or approximately 16,215 of all service laterals include property line cleanouts. Lower lateral maintenance responsibilities include cleaning, inspections, and repairs or replacements. The Wastewater Division is prepared to respond to lateral service calls from customers twenty-four hours a day, seven days a week. Section II-4 and Table II-2 describes how these calls are received and routed to the on-call crew member. In the case of a lower lateral blockage, the on-call crew member clears the blockage, documents the response on Hiperweb and indicates if a CCTV inspection is needed to check the lateral for defects that might warrant repair or replacement. These lateral CCTV inspections are conducted by City staff as needed each Friday (although they can be completed sooner in particularly urgent situations). The CCTV inspection 6.2.A. - Page 39