Sewerage

n. sewer system, system of drainage pipes; sewage, drain water; removal of waste water and refuse by means of a sewer system

Sewerage is the system of sewers that conveys wastewater to a treatment plant or disposal point. The term "sewerage" also includes all the pumps, rising mains, gravity mains, air release valves, screens, overflows and associated infrastructure.It is sometimes incorrectly used to mean sewage.
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Noun
1. waste matter carried away in sewers or drains
(synonym) sewage
(hypernym) waste, waste material, waste matter, waste product
(substance-meronym) effluent, wastewater, sewer water
2. a waste pipe that carries away sewage or surface water
(synonym) sewer, cloaca
(hypernym) drain, drainpipe, waste pipe
(part-holonym) sewage system, sewer system, sewage works

(n.)
The system of sewers in a city, town, etc.; the general drainage of a city or town by means of sewers.
  

(n.)
The material collected in, and discharged by, sewers.
  

(n.)
The construction of a sewer or sewers.
  

The entire system of sewage collection, treatment, and disposal.