Valves Can Prevent Costly, Hazardous Sewage Backup

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Release date: 
June 30, 2004
Release Number: 
1518-040

DES MOINES, Iowa -- As unsettled weather continues to pester Iowans, officials urge homeowners to consider installing backflow valves.

According to the Department of Homeland Security’s Federal Emergency Management Agency (FEMA) and the Iowa Homeland Security and Emergency Management Division (HLSEM), flooding can sometimes cause sewage from sanitary sewer lines to back up into houses through drainpipes. These backups not only cause damage that is difficult and costly to repair, but they also create health hazards.

A good way to protect against sewage backups is to install backflow valves, which are designed to block flow into the house.

Valves vary in complexity, tightness of their seals and ease of operation. For example, gate valves are generally complex and require operation by hand, but they supply a tight seal. Flap or check valves, which allow flow out of the house and close automatically when flow reverses, are simpler. But they do not provide as strong a seal as a gate valve and they require periodic testing.

The following should be kept in mind when installing backflow valves:

  • Local codes and ordinances regarding backflow valves should be checked.
  • Changes to home plumbing must be done by licensed plumbers or contractors, who will ensure that the work is done correctly and according to all applicable codes. Costs are likely to range from a few to several hundred dollars.
  • Some valves incorporate the advantages of both gate and flap valves into a single design. Plumbers and contractors can provide advice on the relative advantages and disadvantages of the various types of backflow valves.
  • Valves should be installed on all pipes that leave the house or that are connected to equipment that is below the potential flood level. So valves may be needed on washing machine drain lines, laundry sinks, fuel oil lines, rain downspouts, and sump pumps, as well as sewer/septic connections.
  • Sump pumps are sometimes connected to underground drain lines, which may be difficult to seal off.

Iowans who experienced losses due to severe storms, tornadoes and flooding between May 19 and June 24 are encouraged to call 1-800-621-FEMA (3362), or TTY 1-800-462-7585 for the speech- or hearing-impaired, to start the application process and get answers to any questions they may have about disaster assistance programs. Recovery specialists are available to take calls from 8 a.m. to 6 p.m. Monday through Saturday.

The Iowa Homeland Security and Emergency Management Division was known as the Iowa Emergency Management Division until July 2003. The current name reflects the dual nature of the Division to provide programs and resources for both homeland security and emergency management efforts.

On March 1, 2003, FEMA became part of the U.S. Department of Homeland Security. FEMA's continuing mission within the new department is to lead the effort to prepare the nation for all hazards and effectively manage federal response and recovery efforts following any national incident. FEMA also initiates proactive mitigation activities, trains first responders, and manages the National Flood Insurance Program and the U.S. Fire Administration.

Last Updated: 
July 16, 2012 - 18:46
State/Tribal Government or Region: 
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