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Home My WebLink About07.a. 2009 COLLECTION SYSTEM SANITARY SEWER OVERFLOW ANNUAL REPORT Central Contra Costa Sanitary District ' BOARD OF DIRECTORS ~` { ~ POSITION PAPER Board Meeting Date: February 4, 2010 No.: ~ •a. Collection System Type of Action: ACCEPTANCE OF REPORT subject: BOARD ACCEPTANCE OF 2009 COLLECTION SYSTEM SANITARY SEWER OVERFLOW ANNUAL REPORT Submitted By: Initiating Dept./Div.: Bill Brennan, Collection System Collection System Operations Department/ Operations Department Director Field Operations REVIEWED AND RECOMMENDED FOR BOARD ACTION: B.-~' Bre M. Kelly, 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 2009 Collection System SSO Annual Report. FINANCIAL IMPACTS: None ALTERNATIVES/CONSIDERATIONS: None BACKGROUND: The 2009 Collection System SSO Annual Report summarizes the overflows that occurred in the District's sanitary sewer system during the period January 1, 2009, through December 31, 2009. This is the fifth SSO Annual Report to be submitted pursuant to the RWQCB's revised requirements for reporting SSOs: The report summarizes the number and size of SSOs, the causes of SSOs, locations of the SSOs, SSO trends, and the status of the preparatiori of our sewer system management plan (SSMP). The collection system experienced arecord-low 63 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 2009 SSO Annual Report to be submitted by March 15, 2010. RECOMMENDED BOARD ACTION: Accept the 2009 Sewer System Overflow Annual Report. CSO/F:\My Documents\MyFiles\annual sso report to the RWQCB\sso 2009 report to the RWQCB\SSO Annual Rpt- 2009.doc DRAFT February xx, 2010 Bruce H. Wolfe, Executive Officer California Regional Water Quality Control Board San Francisco Bay Region 1515 Clay Street, Ste. 1400 Oakland, CA 94612 Attn.: Michael Chee Dear Mr. Wolfe: ANNUAL REPORT OF SANITARY SEWER SYSTEM OVERFLOWS FOR CALENDAR YEAR 2009 The purpose of this letter is to report the Sanitary Sewer System Overflows (SSOs) that occurred in the Central Contra Costa Sanitary District sanitary sewer system during the period January 1, 2009, through December 31, 2009. 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 Overflows, dated November 15, 2004. Number and Size of SSOs The total number of SSOs for the, reporting period was 63. All of the SSOs were associated with gravity sewers. We experienced no overflows as a result of surcharging in wet weather conditions. The sizes of 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 1 2% Between 100 and 999 9 14% Between 10 and 99 40 63% Less than 10 13 21 Public portion of lateral N/A - Total 63 100% 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. Page 1 of 4 Table 2. Volume of SSOs Volume (gallons) Percent of Totai by Volume Total volume contained and returned to sewer system for 2,540 41 treatment Total volume reaching waters 500 8% of the State Total volume not contained but not reaching waters of the 3,085 51 % . State Total 6,125 100% None of the SSOs_exceeded 2,000 gallons in volume. This report does not include SSOs that occurred from private sewer service laterals within the Central Contra Costa Sanitary 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 50 79% Grease 2 3% Debris (rags, rock, paper) 8 13% Debris from laterals - - Vandalism - - Construction debris - - Contractorerror 1 2% Multiple causes - - Subtotal for blockages 61 97% Infrastructure failure 2 3% Inflow and infiltration - - Flow capacity deficiency - - Cause unknown - - Total 63 100% Location of SSOs Of the 63 overflows that occurred during the 12-month reporting period, 53 took place in three of the cities in our service area: Walnut Creek, Orinda and Lafayette. Our Engineering department is currently working on multi-phased rehabilitation projects in Page 2 of 4 these three cities, as welt 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 2009. SSO Trends The following graph shows a comparison of data for the current reporting period with previous reporting periods. Figure 1. Total SSOs 2006 - 2009 Updated through December 2009 Year: 2006 2007 2008 2009 TotalD/Fs by year: YTD comparison: 73 73 81 81 86 86 63 63 Comparison of Cumulative Overflows JAN 8 8 20 ' 7 120 . FEB 9 7 7 5 MAR 5 10 10 8 100 APR 5 8 5 10 MAY 6 10 5 8 JUN 5 4 6 5 80 i JUL 7 6 4 2 AUG 6 5 4 4 60 SEP 3 5 g 5 OCT 3 4 3 0 ~ NOV 8 10 5 2 40 j ~ DEC 8 4 . 9 7 20 ,. . 0 JAN FEB MAR APR MAV JUN JUL AUG SEP OCT NOV DEC °'°A®2006 ®420072008 ~~2009 Status of Development of Sewer Svstem Management Plan (SSMP) CCCSD has complied with the request of the 13267 letter and the SWRCB WDR. Certification I 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 are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Page 3 of 4 Sincerely, William E. Brennan Director of Collection System Operations WEB/rab bcc: E. Boehme (for CCCSD records) J. Kelly Page 4 of 4 7.a Annual Report of Sewer System Overflows Bill Brennan Collection System Operations Department Director February 4, 2010 A Report to the State ^ 63 overflows -lowest in Central San history ^ Total estimated overflow quantity was 78% less than our best-ever year to date ^ 4.2 overflows per 100 miles 1 7.a Overflow quantities Size of SSO (gallons) Number in 2008 Number in 2009 Greater than or equal to 1,000 7 1 Between 100 and 999 19 9 Between 10 and 99 44 40 Less than 10 16 13 Total overflow volume 27,210 gallons 6,125 gallons Overflows comparison 2006 - 2009 Comparison of Cumulative Overflows X20 ~~~ ! ! I f l ~~ ~ i ~ ao so ~ ~ --~ - ~ ~ ~ ~ ; I 20- .;I. ,~ ~~~ 0 JAN R~ MAR APR MAY JUN JUL AUO SFP OCf NOV OEG ~~ -2008 -~Z~~~ -a-Z~~B ~~2~~9 2 7.a Comparative Data for 2009 From State Database • Statewide -Average of 11.5 overflows per 100 miles -Average total SSO volume of 19,000 gallons for the year • Region 2 -Bay Area - Average of 18.2 overflows per 100 miles -Average total SSO volume of 42,500 gallons for the year Overflow causes Cause of SSO Number in 2008 Number in 2009 Roots 63 50 Grease 7 2 Debris (rags, rock, paper) 11 8 All other 5 3 i 3 7.a Geographical trends Walnut Creek ! I i ~ ! I San Ramon ~~! ~ ~~ ~~ ~~ I I I ~ ~ ~ ~ ! Pleasant HIII ~ i ~ ~ i I I Orlnda ~ ~ ~ ~ i ~ ~ ~~ Moraga R ~ i I ~ ~ ~~ ~ ~ Martinez ~ ~ I ~ i I Lafayette ~ ~ ~ I i Diablo ~ ~.~~. . -~ .I Danville nlamo I I ~ ~ ~ o z a e e to tz to to to zo Number of Overtlowa by Cause m Roon ^ Creeee m Othar Contained and treated: Wastewater Treated and Discharged 14,100,000,000 gallons Untreated Wastewater Not 15,957 3,585 Contained gallons in gallons in 2008 2009 Percentage Untreated Less than 0.00003% 4 7.a Overview • 38 days without a single overflow this autumn • "Quality Cleaning" philosophy and follow up with CCTV quality assurance • In January 2008, stopped the practice of lengthening the schedule of lines where cleaning results appeared to be favorable- Overview • Continued reducing scheduled cleaning where significant material was removed. • In November 2008, decided to cut schedules of all six inch and eight inch vitrified clay pipe - 24 month to 12 month and 12 to 6. • Changes in the chemical root control program 5 7.a Overview • Concerted, successful effort made to clean difficult access lines • Use of CCTV to check quality of cleaning • Cleanup of the database to bring the information on the electronic maps (GDI) better into conformance with the CSO maintenance database (ACCELA) Overview • The sewer pi a cleaning is divided into "scheduled" ~CUrrently 420 miles) and "routine" (1,012 miles) cleaning • Scheduled is the designation for pipe with a problem such as roots and is generally less than two years. Routine is the designation for pipes with no known problem • Our goal has been to clean every pipe at least once every five years -routine • With all the other activities in 2009 we are having difficulty meeting this goal 6 Overview • The total number of CSO construction folders completed was 109 (10 by Engineering projects). There were 151 in the backlog in January and 156 by the end of December. This includes those completed in engineering projects • Engineering continued projects to rehabilitate sewers • Changes in method Engineering uses to evaluate lines for replacement -more focus on lines with overflows. • No pumping station orwet-weather capacity overflows Caveats • Dry year • There is a year to year variability • Long term trends are most important • System continues to age • What is good enough for today will not be good enough for tomorrow. 7.a 7.a Regulatory Issues • The SWRCB is reviewing the Waste Discharge Requirement (WDR) for Sewer System Overflows, this may result in more stringent requirements • There is pressure from the portions of the regulatory community as well as non-government organizations for all jurisdictions to take responsibility for maintenance of private sewer laterals. Questions? 8