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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. 1. To download an Excel file, right-click on the file and select “Save link as.” In the “File name” dialog box, add ‘.xls’ at the end of the file name (for example: Cat1-2-3-Spills.xls) to specify the Excel file format. Click the “Save” button to complete the process. The file will be saved to your download file.
  2. The listed “Agency” or “Enrollee” on a sanitary sewer spill report is responsible for the accuracy of the data. For inquiries related to the data, contact the respective agency or Enrollee directly.
  3. Cat1-2-3-Spills: Contains Category 1, 2, and 3 spill data reported under General Order 2022-0103-DWQ since June 5, 2023.
  4. neworder_monthly_counts:  Contains monthly counts for Categories 1, 2, and 3 spills, as well as no-spill and non-Category 1 enrollee-owned/operated lateral spills certification. The file also includes the monthly numbers and volumes of Category 4 spills.
  5. neworder_ssmps: This file includes certification dates for Sewer System Management Plan (SSMP) updates and the next SSMP update due date for enrollees under General Order 2022-0103-DWQ.
  6. No-spill: Contains monthly No-Spill certification statements. These are declarations made through the online CIWQS database, confirming the system did not have any spills during the reporting month.
  7. plps_spills: Contains details of spills from private laterals and private sewer systems voluntary reported by enrollees under the Order, starting June 5, 2023.
  8. PLSD: Contains private lateral sewage discharge data spanning from January 2007 until June 5, 2023.
  9. Enrollee Info: Contains information about the sanitary sewer systems enrolled under the Sanitary Sewer Systems General Order.
  10. Questionnaire: Contains historical information of an enrollee's organization and sanitary sewer system facilities collected under General Order 2006-0003-DWQ. The Questionnaire is referred to as the “Annual Report” in the Order 2022-0103-DWQ.
  11. SSMP: Contains historical records of the completion dates for SSMP elements as required in the General Order 2006-0003-DWQ.
  12. SSO:  Contains detailed information about spill data submitted from January 2007 to June 5, 2023 for each sanitary sewer system WDID number.
    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  is the status of a spill report. "Certified" spill reports are final reports that have been certified for accuracy by the Legally Responsible Official for a particular spill event. Amended spills had been certified but were then updated. There will be multiple rows for a Spill ID if it has been amended. For analysis purposes, only certified spill reports should be used.