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HomeMy WebLinkAbout07.a. Accept the 2010 Collection System Sanitary Sewer Overflow Annual ReportCentral Contra Costa Sanitary District 7Q,. ' BOARD OF DIRECTORS " POSITION PAPER Board Meeting Date: February 24, 2011 subject: BOARD ACCEPTANCE OF 2010 COLLECTION SYSTEM SANITARY SEWER O VERFLOW ANNUAL REPORT Submitted By. Initiating Dept /Div.: Ba T. Than, Provisional Director Collection System Operations Department REVIEWED AND RECOMMENDED FOR BOARD ACTION: T B. Than Jame Ily, General Manager ISSUE: The Central Contra Costa Sanitary District's (District) Sanitary Sewer Overflow (SSO) Annual Report has been prepared for submission to the California Regional Water Quality Control Board (RWQCB), San Francisco Bay Section. This annual report is presented for the District Board of Directors' information and acceptance. RECOMMENDATION: Accept the 2010 Collection System SSO Annual Report. FINANCIAL IMPACTS: None related to this action. ALTERNATIVESMONSIDERATIONS: Not applicable. BACKGROUND: The 2010 Collection System SSO Annual Report summarizes the overflows that occurred in the District's sanitary sewer system during the period January 1 2010, through December 31, 2010. This is the sixth SSO Annual Report to be submitted pursuant to the RWQCB's revised requirements for reporting SSOs. The report summarizes SSOs by the number and size, the volume, the causes, the locations, the trends, and the. status of the preparation of our Sewer System Management Plan (SSMP). The collection system experienced a record -low of 43 overflows last year. Upon acceptance of this Annual Report by the District Board of Directors, it will be submitted to the RWQCB. The RWQCB requires the 2010 SSO Annual Report to be submitted by March 15, 2011. RECOMMENDED BOARD ACTION: Accept the 2010 Sewer System Overflow Annual Report. � 1 -A February 17, 2011 Mr. Bruce H. Wolfe, Executive Officer California Regional Water Quality Control Board San Francisco Bay Region 1515 Clay Street, Suite 1400 Oakland, CA 94012 Attn: Michael Chee Dear Mr. Wolfe and Mr. Chee: ANNUAL REPORT OF SANITARY SEWER OVERFLOWS FOR CALENDAR YEAR 2010 The purpose of this letter is to report the Sanitary Sewer overflows (SSOs) that occurred in the Central Contra Costa Sanitary District (District) sanitary sewer system during the period January 1, 2010, through December 31, 2010. This report is submitted pursuant to the requirements included in the San Francisco Bay Regional Water Quality Control Board Letter, New Requirements for Reporting Sanitary Sewer System Ove rflows, dated November 15, 2004. Number and Size of SSOs The total number of SSOs for the reporting period was 43. All of the SSOs were associated with gravity sewers. We experienced no overflows as a result of surcharging in wet weather conditions. The volumes of the SSOs are summarized as shown on Table 1. Table 1. Number of SSOs Size of SSO (gallons) Number Percent of Total by Number Greater than or equal to 1,000 2 5% Between 100 and 999 13 30% Between 10 and 99 21 49% Less than 10 7 16% Public portion of lateral NIA -- Total 43 100% Page 1 of 4 The volume of spills contained and returned to the sewer system, as well as the volume reaching the waters of the State, is shown in Table 2. Table 2. Volume of SSOs This report does not include SSOs that occurred from private sewer service laterals within the District jurisdiction that were caused by conditions in privately owned laterals or on private property. The property owners are responsible for the condition and operation of those sewer service laterals. Cause of SSOs The predominant cause of SSOs during the period of this report was roots. The distribution of SSOs by cause is shown on Table 3. Table 3. causes of SSOs Cause of SSO Volume (gallons) Percent of Total by Volume Total volume contained and returned to sewer system for 2 12% treatment 4 9% Total volume reaching waters 17 81 /o 0 of the State — — Total volume not contained but — — not reaching waters of the 1 7% State - — Total 21,61 1 100% This report does not include SSOs that occurred from private sewer service laterals within the District jurisdiction that were caused by conditions in privately owned laterals or on private property. The property owners are responsible for the condition and operation of those sewer service laterals. Cause of SSOs The predominant cause of SSOs during the period of this report was roots. The distribution of SSOs by cause is shown on Table 3. Table 3. causes of SSOs Cause of SSO Number Percent of Total Blockage: Roots 34 82% Crease 4 9% Debris (rags, rock, paper) 5 9% Debris from laterals — — Vandalism — — Construction debris — — Contractor error - — Multiple causes — — Subtotal for blockages 43 100% Infrastructure failure — - Inflow and infiltration — -- Flow capacity deficiency — — Cause unknown — — Total 43 100% Page 2 of 4 Location of SSOs The District's Engineering department is currently working on multi- phased rehabilitation projects in these cities, as well as other areas in our service district. The Collection System operations department is expanding its "quality cleaning" program in these areas as well. There were no repeat overflows in 2010. C (Zn Tr©nrie The following graph shows a comparison of data for the current reporting period, 2010 with previous reporting periods from years 2007, 2008, and 2009. rioure i . i otai bbtj5 zuu t — zu1 u [Updated through December 2010 Year: 2007 2008 2009 2010 Total 0/ by year: I 81 861 631 43 Comparison of Cumulative overflows JAN 8 20 7 5 FEB 7 7 5 6 120- . .. .... MAR 10 10 8 3 APR 8 MAY 10 5 5 10 8 5 2 100 JUN 4 6 5 4 80 JUL 6 4 2 1 AUG 5 4 4 2 SEP 5 8 5 2 60 OCT 4 3 0 3 NOV 10 DEC 4 5 9 2 7 5 5 40 20-- f; 711 ,1 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 2007 m1INO2008 ..drw 2009 ­'-*wft2010 Status of Development of Sewer System Management Plan (SSMP) CCCSD has complied with the request of the 13267 letter and the State Water Resources Control Board (SWRCB) Waste Discharge Requirement (WDR). r'.artifinntinn certify under penalty of law that this document and all attachments are prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who managed the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there Page 3 of 4 are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Sincerely, Ba T. Than Director of Collection System Operations B TTIs j Bcc: E. Boehme (for CCCSD records) J. Kelly Page 4 of 4