The legal entity that is responsible for wastewater collection system is Wastewater Collection System Agency. It is also called Sewer System Agency.

In partial sewer systems a part of stormwater during rain is allowed to enter sanitary sewer while remaining stormwater is carried through open drains to point of disposal.

In dry wear flow stormwater is less or absent. During wet wear flow, quantity of stormwater increases. As in partial systems, a part of stormwater is direct to sanitary sewers, stormwater puts a load on treatment plants by increasing quantity of water to be treated.

SSMP stands for Sewer System Management Plan. This is a document that any agency uses to manage wastewater collection system effectively. It helps in improving condition of collection system infrastructure.

In separate systems, two sets of sewers are laid. The sanitary sewage is carried through sanitary sewers while storm sewage is carried through storm sewers. The sewage is carried to treatment plant and stormwater is disposed of to river.

Planning is needed when designing sewer networks. Calculating wastewater flow for community is most essential factor. The calculation of wastewater flow shows size of sewer to be considered.

If a city has less population, it consists of fewer residences and industries based on city needs. Hence quantity of sanitary sewage produced will also be less. It becomes uneconomical to lay separate sewers for both stormwater and sanitary sewage. Hence combined systems are preferred.

If velocity is too less n solid or foreign particles which are very minute in size may settle down. Hence a minimum velocity is required to keep se particles moving along flow is likely to be 3 ft/sec.

Open drains often carry storm water. In rainy seasons water level increases in drains. If it contains clogging or any operations to be done, it becomes difficult if depth is more.

To construct sewer systems certain rules and regulations have to be followed based on quality of pipes chosen, alignment and so on. Pipeline networks are designed by engineers based on city and installed by sewer contractors.