Healthy Community Breakout Session Briefing for Cary, NC

Wed, 2018-06-06 20:50 -- SCC Staff

Challenge statement

Reducing sanitary sewer overflows (SSOs); Improving response speed/effectiveness to SSOs; streamlining wastewater collection system management to make O&M more efficient; ONE Cary integration across systems




  • Preserve Public Health
  • Response Time Reduction
  • Environment Protection
  • Operating Cost Reduction


Specific questions relating to this topic that can inform the discussion

 Describe where Cary should be 6 months, one year and three years from now in this focus area?

What API and Security standards should be required with any implementation?
What are data considerations (i.e. format, retention schedule, correlation, etc.)?
Where does data need to be bi-directional, stored/processed onsite, discarded?
In what sequence should specific wastewater and stormwater technology be implemented/coordinated?
How can data considerations and integrations be expanded or replicated to other communities?


Why is this important?

Sewer overflows place public health, the environment and our natural resources at risk.  These risks affect the health and sustainability of our community. 




Elaborate on challenge statement (what are the specific concerns?)

  • Cost of deploying/managing technology
  • Collection system can have harsh environments – tough/taxing on sensors/equipment
  • Potential # of sensors needed within the collection system to monitor
  • Wireless coverage – service availability, sewers below ground, pump stations in low lying areas

Define solutions that have been implemented to date and those being planned

      Where are we at right now (current state, including initiatives)?

  • Wastewater collection system size (960 miles) & service area
  • # Sanitary Sewer Overflows (SSO)
  • ~19% of collection system cleaned per year, ~80% of the 19% is reoccurring cleaning of same sewer lines. ~4% are new sewer lines cleaned per year.  We focus on cleaning lines that need to be cleaned.
  • 30 Staff for collection system cleaning and inspection
  • Flow monitoring in collection system at 32 fixed locations and 11 mobile units
  • Supervisory Control and Data Acquisition (SCADA) deployed at remote wastewater pump stations and one water reclamation facility


       What have we accomplished so far?

  • Utilizing acoustic pipeline testing to help increase efficiency in inspecting and cleaning higher frequency line cleaning
  • Deployed SCADA at 12 pump stations and at one water reclamation facility and expanding
  • We achieve less than 2 SSO per 100 miles of sewer lines per year. Excessive sewer overflows are deemed to be greater than 4 SSO per 100 miles of sewer line.


Define benefits being sought from new or expanded set of solutions

  • Reduce the amount of citizen calls reporting SSO events
  • Prevent public contact with untreated wastewater (SSO)
  • Protect and preserve the environment
  • Protect natural resources (swimming, fishing, drinking water supplies)
  • Meet permit requirements
  • Increase response time to prevent SSO from occurring
  • Reduce reoccurring cleaning of sewer lines (currently ~80% line cleaned are cleaned more than 1/yr)
  • Eliminate/Reduce # SSO
  • Increase staff/equipment/resource efficiency
  • Free up staff for other more productive work/tasks
  • Increase staff technology skills – expand their capabilities and improve opportunities for growth
  • Automate notification of staff and workorder generation
  • Provide real-time situational awareness information to 311, 911 and other departments

Define additional topics (if any) City wants to explore in working group