Sanitary sewage or Dry weather flow (DWF)/source of sanitary sewage/sanitary engineering

Sanitary sewage or Dry weather flow (DWF):

The flow of sanitary sewage alone in the absence of storms in dry season is known as dry weather flow. It includes waste water from infiltration, commercial establishments, public spaces and industrial zones.

Sources of sanitary sewage:

 Waste water generated by following supply source

a. Public water supply:

Water supplied by the municipal authority for domestic or commercial purpose turns into waste water after some losses. 

b. Private water supply 

Water supplied by private authority for different public spaces like schools, colleges, commercial units etc.

c. Private source 

Private water sources such as well, ground water pumping, canals etc.

d. Infiltration of ground water 

Water accumulated in the sewer line by transmission of ground water though joints.

e. Unauthorized connection 

Any connections that are not considered which designing of sewer line.  Common examples are connecting storm water to the separate type of system carrying dry weather flow, illegal connection from unauthorized waste water generation point.