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Sanitary Sewer System Data Flat Files

All the information collected in the online CIWQS Sanitary Sewer System Database is entered by enrollees. State and Regional Water Board staff cannot enter or modify any information submitted in CIWQS Sanitary Sewer System Database. The CIWQS Sanitary Sewer System Database is accessed through the California Integrated Water Quality System (CIWQS).
NOTE: Please email the SanitarySewer@waterboards.ca.gov inbox with any inquiries.


  1. To save a file as an Excel file, please right-click on the file and choose "Save link as," then use .xlsx as the file name extension and click the "Save" button.
  2. The "agency" or Enrollee listed on a SSO report is responsible for the data should be contacted directly for questions related to their data.
  3. No-Spill contains monthly No-Spill certification statements. "No-Spill" Certification statements are filed through the Online SSO Database certifying that there were no SSOs for the designated month. Note that private lateral spills (PLSDs) may occur during a particular month but, these do not count towards the "No-Spill" Certification. See note 8
  4. PLSD contains Private Lateral Sewage Discharges (PLSDs) data voluntarily reported by participating enrollees since January 2, 2007. See note 8.
  5. PRA contains contact information pertinent to the sanitary sewer systems enrolled and historically enrolled under the SSS WDRs. See note 8.
  6. Questionnaire contains information of an enrollee's organization and sanitary sewer system facilities. The SSS WDRs require enrollees to complete a sanitary sewer system questionnaire and update it every 12 months. See note 8.
  7. SSMP contains completion dates of SSMP elements entered by enrollees. See note 8
  8. SSO contains SSO and PLSD spill data reported by participating enrollees since reporting requirements became effective on January 2, 2007. See note 8.
  9. The SSO Data tables above are all keyed on the sanitary system WDID number. Please note the following information regarding fields in the data tables that pertain to analyses of this data;
    1. Status indicates if an enrollee is either "Active" or "Historical." Active enrollees are those sanitary sewer systems that meet the enrollment criteria and are required to comply with the reporting requirements. "Historical" enrollees are sanitary sewer systems that have been un-enrolled for various reasons (e.g. not meeting the enrollment criteria, erroneous enrollment, etc.) and are no longer required to meet the reporting requirements. For analysis purposes, only "Active" enrollees should be used.
    2. Step the status of a SSO spill reports. "Certified" and "Amended" spill reports are final reports that have been certified for accuracy by the LRO for any particular spill event. For analysis purposes, only certified and amended spill reports should be used.