Glossary of terms
Terms used in designing and checking water, sewer and gas networks — manholes, elevations, slopes, chainage, crossings and longitudinal profiles.
Chainage
Chainage is a way of marking distance along the route axis, measured cumulatively from the start point. It is usually wr…
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…
Elevation
Elevation is the height of a point relative to an adopted vertical datum, usually expressed in metres. In a longitudinal…
Expansion cushion
An expansion cushion (compensation pad) is a flexible foam element placed around a preinsulated pipe where the network e…
Ground level
Ground level is the elevation of the ground surface at a point along the route, given in metres relative to the vertical…
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…
Invert level
The invert level is the elevation of the lowest inside surface of a pipe or channel at a given point, given in metres re…
ISYBAU
ISYBAU (Integriertes DV-System Bauwesen) is the German data exchange standard for sewer networks, developed by the feder…
Longitudinal profile
A longitudinal profile is a drawing that shows a network route in section along its axis: chainage horizontally and elev…
Pipe reach
A pipe reach (German Haltung) is the run of pipe between two adjacent manholes — the basic unit for which length, slope,…
PL-2000 offset
PL-2000 is the Polish plane coordinate system in which northing coordinates may reach values of several million metres.…
Preinsulated pipe
A preinsulated pipe is a factory-bonded assembly of three layers: a steel service (carrier) pipe, rigid polyurethane (PU…
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…
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…
Sewer manhole
A sewer manhole is a structure placed along a sewer line to connect sections, change direction, slope or diameter, and p…
Sewer slope
Sewer slope is the inclination of the channel invert in the direction of flow, usually expressed in per mille (‰) or as…
Title/data band
The data band (German Schriftband or Datenband) is the table placed below the graphical part of a longitudinal profile,…
Utility crossing
A utility crossing is a point where the designed route intersects another underground utility such as a water main, gas…
Vertical exaggeration
Vertical exaggeration is the deliberate use of different horizontal and vertical scales on a longitudinal profile — the…