Glossary of terms

Terms used in designing and checking water, sewer and gas networks — manholes, elevations, slopes, chainage, crossings and longitudinal profiles.

Sewer manhole

A sewer manhole is a structure placed along a sewer line to connect sections, change direction, slope or diameter, and p

Chamber

A chamber is an enlarged network structure, larger than a typical manhole, used where space is needed for valves, fittin

Drop structure

A drop structure is used in a manhole when the incoming sewer invert is much higher than the outgoing invert and a direc

Chainage

Chainage is a way of marking distance along the route axis, measured cumulatively from the start point. It is usually wr

Elevation

Elevation is the height of a point relative to an adopted vertical datum, usually expressed in metres. In a longitudinal

Sewer slope

Sewer slope is the inclination of the channel invert in the direction of flow, usually expressed in per mille (‰) or as

Service connection

A service connection is the section that links a main pipe or sewer to a customer's internal installation, such as a bui

Utility crossing

A utility crossing is a point where the designed route intersects another underground utility such as a water main, gas

PL-2000 offset

PL-2000 is the Polish plane coordinate system in which northing coordinates may reach values of several million metres.

Longitudinal profile

A longitudinal profile is a drawing that shows a network route in section along its axis: chainage horizontally and elev

Route

A route is the planned course of a network in plan view: a sequence of points and sections from the start to the end of

Hectometre

A hectometre is a distance unit equal to 100 metres and is used in station notation. The format a+bbb.bb means full hund