Every community produces both liquid and solids waste and air emissions. The liquid waste – waste
water is consensually the water supply of the community after it has been used in a variety of
applications. From the stand point of generation, waste water has been defined as a combination of
liquid or water carried waste removed from residences, institution and commercial and industrial
establishments, together with such ground water, surface water and storm water as may be present.
Sanitary engineering is the branch of civil engineering associated with water, disposal of sewage and
other public health services. It consists of scientific and methodical collection, conveyance, treatment
and disposal of the waste matter, so that the public health can be protected from offensive and
Waste water engineering is that branch of environmental engineering in which the basic
principles of science and engineerijg are applied to solving the issues assossiated with the
treatment and reuse of waste water.
Sewage, sewer and sewerage system
Sewage, is the wastewater resulting from a acomminity. sewage are mainly of 2 types:•
Domestic sewage : This consists of liquid wastes originating from urinals, toilets, bathrooms,
kitchen sink wash basins etc. of the residential, commercial or institutional buildings.
Industrial sewage : this consists of liquid wastes originating from the industrial process of various
industries. The quality of the industrial sewage depends largely on the type of industrial sewage
depends largely on the type of industry and the chemicals used.
Storm water : Storm water or storm sewage or storm drainage is the run off resulting from the
Sewer: Sewer is the underground conduit or the pipes through which sewage is carried to a point
of discharge or disposal. ‘Drains’ carry stormwater.
Sewerage system: A sewerage system consists of a network of sewer pipes laid inorder to carry
the sewage from individual homes to sewage treatment plant. This network of sewers may consist
of house sewers(or individual home connections); lateral sewers(or submains); main sewers
(generally called trunked sewers);outfall sewer(the sewer which transports sewage to the point of
Manholes are provided in every sewer pipes at suitable intervals so as to facilitate their cleaning
and inspection. In sewers which carry storm waters solely or in combination with sewage, inlet
called catchment basins are provided to permit entrance of storm water.