Sanitary Sewers
Sanitary Sewer
A sanitary sewer is a separate underground carriage system specifically for transporting sewage from house and commercial building sewer laterals to treatment or disposal. Sanitary sewers serving industrial areas also carry industrial wastewater.
Sanitary sewers are operated separately and independently of storm sewers, which carry the runoff of rain and other water which wash into city streets.
Sewer Lateral
A sewer lateralOf, at, toward, or from the side or sides. is the pipeline that connects the property to the local sanitary sewer main. The sewer lateralOf, at, toward, or from the side or sides. is owned and maintained by the property owner including any part which may extend into the street or public right-of-way.
Sewer Main
A sewer main is a utility pipeline that transports wastewater from connected lateralOf, at, toward, or from the side or sides. lines to the wastewater treatment plant, either through a gravity system or a pressurized sewer force main. In the City of Racine, smaller diameter sewer pipes are owned, operated, and maintained by the City itself. The larger pipes, known as interceptors, are owned, operated, and maintained by the Racine Wastewater Utility.
Within Racine’s sanitary sewer system, approximately 79% of the infrastructureThe basic...
Sewer Force Main
A force main is a pressurized main pipe which can carry sewage counter gravitationally (from lower to higher elevations). A force main pipeline carries wastewater from a sewage lift station to other pipes further along in the system. The word “force” refers to the fact that the pipeline is under pressure, rather than relying on gravity to move wastewater.
Force mains are used to convey wastewater from a lower to higher elevation, particularly where the elevation of the source is not sufficient for gravity flow.
Gravity Main
Gravity mains are extensive underground pipe networks that transport wastewater from individual homes to a centralized treatment facility using the natural force of gravity. These systems are typically organized into multiple levels: primary mains run along major roads, secondary mains connect smaller areas, and tertiary mains serve neighborhoods and individual properties.
Unlike some other systems, gravity mains do not require onsite pretreatment or wastewater storage. Since the wastewater flows untreated, the pipes must be designed to maintain a self-cleansing velocity—meaning the flow must be strong...
Sanitary Lift Station
When a downhill grade cannot be maintained, a lift station must be installed. Primary sewers are laid beneath roads, and must be laid at depths of 5 to 9 feet to avoid damages caused by traffic loads.
A lift station pumps or lifts the waste stream from low lying areas to higher lying areas, so gravity can carry the flow to the treatment plant. Some areas must be pumped because the gravity areas are not possible.
Checks are performed on each station daily and records...
Sanitary Manholes
Periodically, a vertical pipe will run up from the main to the surface, where it is covered by a manhole cover. Manholes allow access to the main for maintenance purposes.
Access manholes are placed at set intervals along the sewer, at pipe intersections and at changes in pipeline direction (vertically and horizontally). The primary network requires rigorous engineering design to ensure that a self-cleansing velocity is maintained, that manholes are placed as required and that the sewer line can support the traffic weight. As well,...
Sanitary Sewer Maintenance
The City of Racine has a maintenance and cleaning program to keep the sanitary sewer system operating efficiently and to minimize the number of calls for service. The City contracts with the Wastewater Utility to provide this maintenance program for them. Some problem areas in the City are cleaned more frequently than others.
Sewer cleaning using hydraulic or mechanical methods performed on a routine basis helps to remove accumulated debris in the pipe such as sand, silt, grease, roots and rocks. If debris is allowed...
Sewer Flushing
The Racine Wastewater Utility uses high-pressure sewer Vactor jet trucks to clean the sanitary sewer system. To clean sanitary sewers the Utility uses high-pressure water to propel a jet nozzle at the end of a specialized hose through the sewer pipeline, breaking through obstructions and blockages. A flushing nozzle is installed on the end of the jet truck’s hose and the hose is lowered into the downstream manhole of the sewer section being cleaned.
This method uses high-pressure water to flush out stone, sediment or...
Sewer Lateral/Tree Conflicts
Residents occasionally submit complaints to the City indicating they have roots in their sewer lines causing poor drainage and other issues.
Root growth into a sewer occurs where the sewer lines have been damaged by factors such as soil compaction and aging sewer laterals. The roots themselves do not cause the original sewer line damage but may result in blockages and further pipe breakdown.
Nutrients, oxygen and warm temperatures inside cracked or eroded pipes attract and encourage rapid root growth, filling the pipe with multiple...
Grease
The Racine Wastewater Utility is committed to protecting our natural resources.
One of the main causes of back ups from the sanitary sewer system is due to clogs in the sewer piping system from cooking oil and grease. This material solidifies in the sewer lines and restricts flow, sometimes completely.
Oil and grease enters our collection system most commonly through users pouring used cooking oil down a drain or during the cleaning operationsThe fact or condition of functioning or being active.at food service...
