Iowa Department of Natural Resources Environmental Services Division For Immediate Release July 17, 2007 STORMS OVERWHELM IOWA WASTEWATER SYSTEMS MEDIA CONTACT: Karen Grimes at (515) 281-5135 or Dennis Ostwinkle at (319) 653-2135. DES MOINES -- Following heavy storms across eastern and northern Iowa Monday evening, communities are reporting wastewater bypasses to the DNR on Tuesday. When wastewater treatment facilities are "bypassed," sewage is not treated before it is sent directly into a body of water. This can occur as a result of mechanical failures and power outages, but also from heavy rainfalls or snowmelts. Heavy rain can overload wastewater collection systems, which are the underground sewer pipes that carry sewage to a treatment plant. With sewage pipes overwhelmed, excess water has nowhere to go, and can backup into basements through floor drains. Bypassing can lower the water level in the collection system, keeping sewage from backing up into basements, which would present health risks. This can happen when large amounts of rainwater or snowmelt, also called storm water, enter a sanitary sewer from cracks in sewer pipes. It can also enter from improper connections, such as roof drains or sump pumps hooked up to the sanitary sewer system instead of the storm water system. Rain water should enter the storm sewer system, which receives no treatment before entering a stream or lake. Instead, storm water enters and overwhelms the sanitary sewer system (which treats wastewater from homes and businesses). "Communities need to inspect their sewage pipes, as well as check for sources of storm water getting into the system. They need to work with homes and businesses to keep storm water from entering the sanitary sewer," said Dennis Ostwinkle, DNR's wastewater compliance coordinator and head of the DNR's Washington field office. According to DNR design standards for construction of new wastewater treatment systems, facilities should be able to handle the amount of water in the collection system from all three of these events happening at the same time: * Peak sewage flows from homes, businesses and industry * Peak groundwater levels * A storm that drops two inches of water in an hour. Many collection systems in Iowa already have or are in the process of upgrading their collection systems to handle these events, but many more need to upgrade. The DNR tracks bypass reports submitted by facilities and follows up with the facility to determine problems and help them upgrade their systems, although it can be a long-term process. The DNR has also formed a committee to discuss how it handles wet weather bypasses. Facilities are required to report bypasses caused by mechanical failures to the DNR within 12 hours of onset or discovery. Facilities do not have to immediately report bypasses from precipitation events, but must include them in their monthly operating report to the DNR. The following communities have reported bypasses to the DNR: Des Moines County Burlington: An estimated 285,100 gallons of untreated wastewater began bypassing from three of Burlington's four sanitary sewers Tuesday morning. The diluted mixture of wastewater and storm water began overflowing from the Brooks, Burlington Northern and Lucas/Mt. Pleasant sewer locations in the Hawkeye storm sewer line at 7:45 a.m. Tuesday after more than 1.6 inches of rain fell in the area within 24 hours. The bypass ended by 11:30 a.m. with the discharge flowing to the Mississippi River. Downstream water supplies have been notified of the discharge. The City of Burlington is working to install holding tanks on the Hawkeye storm sewer to prevent these types of overflows. The city plans to complete the project by October 2008. Howard County: Elma: The City of Elma began bypassing at 6 a.m. Tuesday after heavy rain showers caused its treatment plant to flood. Elma's treatment plant will wait for the excess flow to diminish before continuing its operations. The unknown amount of wastewater is entering Mead Creek, which flows to the Little Wapsipinicon River. Jefferson County Fairfield: After receiving heavy rainfall Monday, the City of Fairfield began bypassing approximately 13,500 gallons of untreated wastewater from its collection system. At 9:10 p.m. Monday, the discharge began bypassing to an area pasture, where it next entered a drainage ditch that flows into Crow Creek. The bypass ended before 10 p.m. Monday. The City of Fairfield has experienced frequent wastewater bypassing but is in the process of developing a plan to address this problem. Linn County: Cedar Rapids: The City of Cedar Rapids began bypassing untreated wastewater from several discharge points to the Cedar River due to flash flooding in the area Monday evening. The bypass began at 9 p.m. Monday with two of the city's sanitary sewers and five manholes overflowing. Cedar Rapids Water Pollution Control reports the bypass ended by 12:30 p.m. Tuesday, with trash pumps being used to control the overflow. Discharge totals remain unknown. Muscatine County West Liberty: West Liberty's wastewater treatment plant is bypassing diluted wastewater to a local tributary of the Cedar River. After receiving more than two inches of rain Monday evening into Tuesday morning, the treatment plant's wet well is discharging to Wapsinonoc Creek. Amounts remain unknown. Writers: Holly Williams and Jessie Brown -30- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - To unsubscribe from the IOWA-TOPICS list, send any message to: [log in to unmask] Check out our Listserv Lists support site for more information: http://www.sierraclub.org/lists/faq.asp