Sanitary Sewer Backflow Prevention

Every year, OMAG receives 1,000 (+/-) tort claims that are filed against municipalities that participate in the Municipal Liability Protection Plan (MLPP). Sanitary Sewer Overflows (SSOs) are one of the most frequently filed claims we receive. In the past 10 years OMAG has paid over 6 million dollars in damages due to SSOs. In a recent interview with Todd Lansdown, Wastewater Maintenance Supervisor with the City of Bartlesville since 1981, Todd recommended these “BEST PRACTICES” to assist in SSO prevention and dealing with customers who have had one of these  unfortunate events. He noted that these policies and procedures are not all his own ideas—they’ve been passed down and refined over the years.

  • Map your system—Number EVERY manhole.
  • Set and publish an expected “RESPONSE TIME”, for SSOs such as “The City will respond to all SSO calls within 20 minutes during business hours or within one hour on weekends and after hours.
  • Have a SEWER COMPLAINT form that is filled out when the call comes in. It should identify the date, time of call, who called, phone number, who received the call and a description of the customer complaint.
  • The SEWER COMPLAINT should automatically generate a WORK ORDER. It should show the date, who filled it out, have room for several addresses and have an area to describe exactly what conditions were found and what work was   performed. Several addresses could be involved in one event so that is why there should be room for multiple addresses on the work order. Bartlesville’s WORK ORDER also shows Regular or Overtime hours, the number of workers and hours worked and all trucks and equipment that were used on the call. The work order is returned to the office where it can be stored for future reference and to make contact with the customer to let them know exactly what work was performed and answer any      questions that they may have. 
  • COMPLAINTS and WORK ORDERS should be retained in accordance with your records retention policy and the Oklahoma Open Records Act, 51 O.S.2011, §§ 24A.1 to 24A.29. These records are very important if a tort claim is filed against the municipality. They also can assist you in identifying problems with your sewer system if there are complaints from one or more addresses in the same area.  Microsoft Excel is a reliable spreadsheet to use for storing and tracking these records.
  • When employees describe the work performed on a service call do not allow them to simply write “Everything is OK”.  If the municipality’s sewer main was flowing, have the employee actually write “line was flowing—no obstructions”. If something was found in the line, have them describe exactly what was found, such as “line flowing half-full, we removed sticks. Normal flow when we left at 11:20 pm”. 
  • If there is a backup always rod/jet the line from the downstream manhole to the upstream manhole—and ALWAYS go from manhole to manhole—don’t stop in between manholes. It’s possible that there could be more than one obstruction in the line.
  • If the municipality’s sewer line caused a backup and normal flow is achieved, Bartlesville always performs a video camera inspection to identify the cause of the backup. The camera is inserted into the sewer main and viewed from upstream to downstream. 
  • Any time there is a backup in Bartlesville, it automatically triggers a maintenance program. This consists of jetting the line at least once a year. If there are more backups reported in the same area in less than one year from the initial call, the line is   video inspected again. Todd said that more than one call in less than a year signals a problem that needs to be fixed. 
  • On lines where root intrusion is causing backups it is a good practice to treat the roots with a herbicide to kill them. “Diquat” brand root killer is the product that Bartlesville uses. A herbicide applicator’s license is not required for the use of this chemical and it also will not kill trees. Diquat works best when it is applied to roots after they’ve been allowed to grow out at least 6 to 8 months. The longer the roots are, the  better the chemical works. The herbicide usually lasts 3 to 4 years and helps reduce the amount of time needed to jet the lines. Bartlesville uses Diquat foam in problem areas every 4 to 5 years when funding is available.
  • Employees must be allowed to work ONLY on the municipality’s lines. Obstructions in private sewer service lines are the responsibility of the property owner/occupant. Public labor and equipment cannot legally be used to work on private lines.
  • Sewer mains should not be tapped by private contractors/plumbers. Vitrified clay pipe must be cut with a diamond blade saw to get a smooth, clean cut that helps in sealing out roots. 
  • Bartlesville allows “ROMAC” brand tapping saddles on vitrified clay pipes because they have steel bands that go completely around the   sewer main and securely fasten the tapping saddle to the main. “These saddles work much better than PVC saddles because the PVC saddles have a rubber gasket that allows movement of the saddle due to settling or ground moving events,” Lansdown explained. “When the tapping saddle moves, it breaks the seal of the pipes and allows the entry of roots.” 
  • All sewer line taps are inspected by city inspectors for proper materials and workmanship.
  • Backflow valves are required on service lines that have a floor elevation that is lower than the closest upstream manhole. Backflow valves must be  maintained at least every year. They work on a principle of a plastic flap that allows the flow of sewage in only one direction. There must be access to the valve so the flapper can be washed. There should be directional cleanouts installed on both sides of the valve so that sewer rodding machines cannot damage the flapper in the valve. Several municipalities require backflow valves on all new construction and service line replacements. 
  • Another overflow device is a “pop-off cap”. It is  installed above ground on the service line’s cleanout. In the event of sewage flowing in the  service line in the wrong direction, the cap simply floats off of the cleanout pipe. This device allows sewage to overflow onto the ground    instead of inside the building. See the photo below. 
  • Employees that respond to sewer backups should not offer personal opinions or offer   information about fault or liability. They should be trained to only offer that “the line is flowing” OR “the line was not flowing and we cleared it” and nothing more. It is not their responsibility to determine fault or liability. Todd also coaches his employees to carry a spiral notebook in their trucks. He tells them to write notes about everything they can remember that the customer said even if it didn’t apply to the sewer event. He explained using this  example of a note taken by one of his employees.  “The lady told me that she was baking cookies when she smelled a foul odor and found sewage backing up into the tub. She went on to explain that they had sewer problems in the past and  didn’t call the city immediately because her husband was able to use a plunger to take care of it”.  When these cases go to court the claimant’s story often changes.  If a defense attorney is able to refer to specific notes taken by city employees during a sewer event when questioning a claimant, the claimant frequently must acknowledge that the event didn’t happen exactly as they reported it in the claim.

Closing the interview, Todd left us with a couple of thoughts.  "DOCUMENT, DOCUMENT, DOCUMENT everything - you can't over-document!" and lastly "Be honest, fair and even. Provide the same services for all your customers that you would provide for the Mayor."

Assisting our member cities and towns in reducing costs caused by Sanitary Sewer Overflows (SSOs) is a priority with OMAG’s Risk Management Department. If you are considering purchasing a sewer camera or if several decision-makers in other communities in your area are interested in buying one and sharing, OMAG will pay matching funds to each participating municipality up to $3,000 each on a first come, first served basis. Contact Gary Cauthen  at (800) 234-9461 or gcauthen@omag.org for more information.

Print Friendly and PDF