Improving Our Community Waterways Together

MSD's Overflow Reduction Operating Programs

Nine Minimum Controls (NMC)

The Nine Minimum Controls are identified as minimum technology-based controls that can be used to address CSO problems without extensive engineering studies or significant construction costs, prior to the implementation of long-term control measures. 

The nine controls are as follows:

  1. Proper operation and regular maintenance programs for the sewer system and CSO outfalls
  2. Maximum use of the collection system for storage
  3. Review and modification of pretreatment requirements to ensure that CSO impacts are minimized
  4. Maximization of flow to the POTW for treatment
  5. Elimination of CSOs during dry weather
  6. Control of solid and floatable materials in CSOs
  7. Pollution prevention programs to reduce containments in CSOs
  8. Public notification to ensure that the public receives adequate notification of CSO occurrences and CSO impacts
  9. Monitoring to effectively characterize CSO impacts and the efficacy of CSO controls.

Per Paragraph 24.a. of the Amended Consent Decree, the Nine Minimum Controls (NMC) Compliance Report was initially submitted to EPA and KDEP on February 10, 2006.  The approved submittal is dated September 15, 2006.  MSD received an approval letter, dated February 22, 2007, for the NMC Compliance Report.  The approved NMC Compliance document can be viewed in the Library.  Annual program updates to this original document can be found in the Consent Decree Annual Reports. 

Capacity, Management, Operations and Maintenance (CMOM) 

CMOM stands for “Capacity, Management, Operations, and Maintenance”.  If is a flexible, dynamic program for municipalities to identify and incorporate widely accepted wastewater industry practices to:

1. Better manage, operate, and maintain collection systems
2. Investigate capacity constrained areas of the collection system
3. Respond to sanitary sewer overflow (SSO) events

In CMOM planning, the utility selects performance goal targets, and designs CMOM activities to meet the goals.  Information collection and management practices are used to track how well each CMOM activity is meeting the performance goals, and whether overall system efficiency is improving.

Per Paragraph 24.c of the Amended Consent Decree, the Capacity Management Operations and Maintenance (CMOM) Self Assessment Report was submitted to EPA and KDEP on February 10, 2006. The approved submittal is dated May 12, 2006.  MSD received a letter of approval on August 22, 2006. The approved CMOM document can be viewed in the Library. Annual program updates to this original document can be found in the Consent Decree Annual Reports.

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