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HomeMy WebLinkAboutItem KAGENDA REPORT DATE: April 22, 2002 TO: Honorable Mayor and City Council THRU: John B. Bahorski, City Manager FROM: Doug Danes, P.E., Director of Public Works, City Engineer SUBJECT: INTERIM REPORT ON THE SEWER MAIN -LINE CLEANING AND VIDEO INSPECTION PROJECT, No. 50039 AND 50040 SUMMARY OF REOUEST: The proposed City Council action will receive and file the presented information for the Sewer Main -line Cleaning and Video Inspection Project, No. 50039 and 50040. BACKGROUND: The City of Seal Beach provides sewer service within the City boundaries. Surfside, College Park West, a portion of College Park East and Leisure World are sewered through other districts or directly to the Sanitation District. Typical wastewater flow generated within the City's service area average 1.5 million gallons per day. The existing wastewater collection system maintained by the Public Works Department is made up of gravity sewers, pump stations and sewer force mains. The gravity systems consists of approximately 30 miles of pipe and 650 manholes. The majority of the piping system is Vitrified Clay Pipe (VCP) with fewer sections of plastic, cast iron, and ductile iron. Maintenance on the system includes regular inspections and preventative maintenance of the system, the pump stations and of the "hot spot" locations. Staff also endeavors to maintain good record keeping practices. Pump Stations and key locations are inspected daily by staff and all City owned sewer main lines are cleaned annually. In February of 1999, the City completed a comprehensive Sewer Master Plan to evaluate the existing sewer system, identify future capacity deficiencies, and recommend cost effective system improvements to relieve existing and future deficiencies. Particular attention and interest have been directed towards wastewater systems because of their potential for environmental harm. New requirements from the Environmental Protection Agency (EPA) and the Regional Water Quality Control Board will focus more energy into the maintenance and operation of the system. Sanitary Sewer Overflows, (SSO) which flow to a storm drain system and to the ocean are unacceptable and sewer districts can be severely fined and penalized. Another concern is that leaky and broken sewer lines could leach into the ground polluting the groundwater and/or the beaches. Agenda Item A The typical design life for wastewater systems is 30 -50 years and the City has components which are nearing 80 years of service. The City has maintained an aggressive program to replace system components which are at the end of their design life. Sewer fees and grants in the Capital Improvement Program, approximately fund $500,000 annually to replace sewer lines and a bond has programmed the replacement of over $3,000,000 of sewer pump station improvements. In a proactive policy to further identify hidden situations within the system, the City applied for a matching grant from the Orange County Sanitation District to clean and video sewer lines in the Old Town Area and in College Park East during the fiscal year 2001 /2002. The work consisted of first cleaning approximately 17 miles of the sewer pipes followed by methodical video monitoring, inspection and video - taping to identify sags, dips, misaligned and/or separated joints; protruding and/or defective laterals; erosion and corrosion; cracks and other structural problems. The basis of the project was to determine if there are sections of sewer main line which were experiencing infiltration or inflow which added to the extraneous flow delivered to the Sanitation District's treatment facility. In addition, the project provides a comprehensive report on the condition of the sewer lines. Old Town was chosen because of the age of the pipes and College Park East was chosen because of the high ground water table in the area. The majority of the cleaning and inspection project has been completed and the initial results are being reviewed and analyzed by Staff. No significant or prominent problems or situations requiring immediate action were found. City consultants will complete a more detailed review of the reports and tapes of the 17 miles of sewer lines and assist staff in prioritizing the projects through the CIP. The common deficiencies found in the system were root infiltration, grease build -up, protruding laterals, cracked pipe, broken pipe, pipe sags, and offset joints and as mentioned, no immediate situations were found from the initial reports. Locations identified with heavy roots or grease have been scheduled or been repaired by the Public Works Department. The vast majority of these deficiencies were found in the Old Town area, which can be contributed to the age of the pipes. The College Park East sewer system was found to be in good operating condition. Deficiencies similar to these found in our system are very common to all sewer systems. They are caused by old age, below ground earth movements and a corrosive sewage environment. The Engineering Division will be further analyzing the video reports and tapes. The final analysis will develop new priority repair locations, update costs, and tie -in a Capital Improvement Program with the Sewer Master Plan. Staff will be reviewing all options for construction including the traditional open -cut remove and replace, cured in place plastic slip - liners, pipe bursting and robotic spot repairing. In addition to the video inspection, staff performed a dye test with the pump stations adjacent to the beach to confirm that there were no leakages with the force main sewer lines. Staff was concerned with recent beach closures and reassured that the City's system was not contributing to the problem. These test indicated that the system was not leaking sewage. The goal of the City is to be proactive towards all water quality concerns and issues by applying for grant funding when available, developing water quality and sewer system master plans, exploring details of City facilities and infrastructure, educating the public, and adhering to the water quality rules set by the regional water quality board. From these applications, the City develops the Capital Improvement Program which implements the construction of these projects. Agenda Item _ The City also endeavors to set an example to other cities to further improve regional water quality to reduce beach and river closures. FISCAL IMPACT: Funds in the amount of $110,800 including construction management of the project have been programmed. Funds in die amount of $74,000 for College Park East and $46,800 for Old Town are budgeted in the City's Capital Improvement Program. $55,000 of the budgeted funds will be provided by Orange County Sanitation Districts Cooperative Projects Program in accordance with the Contract executed on September 6, 2001 between the City and OCSD. Rehabilitation, repairs, upgrades, and further maintenance costs have not been determined at this time. However, based on the existing Capital Improvement Program, the costs are estimated to exceed $10 million dollars. RECOMMENDATION: Staff recommends that the City Council receive and file the presented information for the Sewer Main -line Cleaning and Video Inspection Project, No. 50039 and 50040. Prepared By: Mark L Vukojevic, P.E. Assistant City Engineer Revie d By' Dg . ancs, ., rector of Public Works/City Engineer Agenda Item