Sanitary Sewers

A sanitary sewer is a type of underground carriage system, for transporting sewage from houses or industry to sewage  treatment facilities. 

Ideally sanitary sewer systems are operated separately from storm water systems but when sewers carry both sewage and storm water together they are called combine sewers.

Sewers are usually pipelines that begin with connecting pipes from buildings to one or more levels of larger underground trunk mains, which transport the sewage to sewage treatments facilities.  Vertical pipes, called manholes, connect the mains to the surface.  The manholes are used for access to the sewer pipes for inspection and maintenance.  They also facilitate vertical and horizontal angles in otherwise straight pipelines.  Sewers are generally gravity powered, though pumps may be used if necessary.  

Links of Interest

Construction Project Statuses

Sewer Private Property Protection Program - Residential Example of Inflow and Infiltration Sources

Historical Sanitary Sewer Map 

Storm Sewer Maintenance

The sewer division is responsible for maintenance and management of 471.62 miles of storm sewer, 8,030 storm manholes, 12,125 storm inlets, 52 miles of ditches, and 21.5 miles of levee maintenance.  Pipe sizes making up the current collection system for storm water range from 6" to 10 feet by 5 feet box. 

Stormwater Maintenance

The Stormwater Utility Division is responsible for stormwater management planning and engineering including flood control and mitigation, responding to residents’ drainage concerns, and improving surface water quality within the City of Des Moines.  For more information, please see the Links below:

Flood Control and Mitigation

Drainage Concerns

Water Quality

Easter Lake Public Meeting Factsheet

What is a Storm Sewer?

A storm drain, stormwater drain, or storm sewer system is designed to drain excess rain and groundwater from paved streets, parking lots, sidewalks, and roofs.  They are fed by street gutters on most motorways, freeways and other busy roads, as well surface runoff from other areas during rain events.  Most storm sewer systems are designed to handle smaller more frequent storms.  During heavier, infrequent storms some street ponding is expected, and sometimes water may run to a natural drainageway. 

Function of Storm Sewer

Inlet 

There are two main types of stormwater drain (sewer) inlets; side inlets and grated inlets.  Side (or curb inlets) are located adjacent to the curb and rely on the ability of the opening to capture the water flow.  Grated inlets have gratings or grids to prevent large objects and debris from falling into the sewer system.  However their bars are fairly widely spaced so that the flow of water is not impeded. 

Piping

Pipes can come in many different shapes (rectangular, square, oval and more commonly, circular) and have many different features.  Several different materials can also be used, such as brick, concrete, or less frequently, metal.

Outlet

Most drains have a single large exit at their point of discharge (often covered by a grating) into a canal, river, lake or reservoir.  In Des Moines all stormwater eventually drains to the Des Moines or Raccoon River, either through a direct discharge from the storm sewer system or after making its way to a larger creek, such as Walnut or Four Mile Creek.

Typically, there are no treatment facilities in the piping system other than catch-basins. In some cases, storm drains may discharge into man-made excavations known as detention or retention ponds before being discharged to a water body.

Report a Problem

To report any stormwater pollution concerns, such as illicit discharges, drainage concerns, connections or polluted runoff from a construction site please contact the City's 24-Hour Hotline at (515) 283-4950 or submit a online concern.

City & WRA Launches $220 Million in Sewer Improvements

Sewer projects estimated to provide millions of dollars in construction jobs.

The Des Moines Metropolitan Wastewater Reclamation Authority (WRA) and the City of Des Moines will continue an extensive rebuild of the city’s sewer system that provides for $220 million in sewer construction between now and 2013. This investment will improve central Iowa water quality and reduce the risk of property damage during high rains.  

The sewer improvements will meet or exceed Iowa and Federal environmental requirements to separate and treat sewage and reduce the mixing of storm and sanitary sewage. The City and the WRA have entered into a consent decree with the Iowa Attorney General’s Office to move forward with plans to separate storm and sanitary sewers where possible and to treat combined storm and sanitary flows at a new high flow facility that will be built within the City of Des Moines. Construction of the estimated $50 million high flow facility is expected to provide millions of dollars in construction jobs and give metro Des Moines sewer customers the benefit of a state of the art facility.

The combined sewer area of Des Moines is roughly the portion of the city lying east of 42nd Street and west of East 18th Street, south of Euclid Avenue and north of the Des Moines and Raccoon Rivers. The area is designated by the yellow shading on the  map.

“Although our current sewer system met state standards when constructed,” said William Stowe, WRA and Des Moines Public Works Director, “It is the WRA and City of Des Moines’ responsibility to comply with new Iowa and Federal mandates to separate and treat sewage in a way the meets or exceeds environmental requirements. We choose to lead statewide efforts to improve water quality, particularly on the Des Moines River. This decision to invest nearly a quarter of a billion dollars will underscore the vitality of area waterways and WRA commitment to environmental leadership. ”
 

The WRA is a consortium of Des Moines Metro area communities, counties and sewer districts that work together for wastewater treatment and cleaner rivers in central Iowa. The WRA treats the wastewater from nearly 500,000 connected customers, commercial facilities and industries at the Wastewater Treatment Facility at 3000 Vandalia Road in Des Moines. At this facility, nearly 25 billion gallons of treated water are discharged into the Des Moines River.

For more information see Engineering, or contact William Stowe, WRA and City of Des Moines Public Works Director.