Overview
Detailed watercourse mapping
OS MasterMap Networks - Water Layer provides a detailed centre line following the curve of the waterway precisely. It includes the coordinates of watercourse sources and where they meet, exactly.
Content and context
With this water network data, you can look up the height of any water course, along with its flow direction, gradient, length and width anywhere along its length.
How far, how wide
As an island, water defines Great Britain. No other visualisation of our nation’s watercourses details the heights of watercourses in relation to sea level with this level of precision.
Complete picture
For planners, for surveyors, for engineers – this Layer offers the potential to model in 2D and 3D like never before, thanks to the clarity of river flow, gradient and river widths.

Answers on tap
From aqueducts to tunnels, with annotations of flow direction, OS MasterMap Water Network Layer provides the detailed mapping that’s most useful – including underground watercourses (inferred from entry and exits).

Content and context
OS MasterMap Networks - Water Layer provides a detailed centre line following the curve of the waterway precisely. It includes the coordinates of watercourse sources and where they meet, exactly.
Technical specification
Key Features | What this product offers |
---|---|
Format | GML 3.2 |
Data structure | Vector - topologically structured link and node network |
Attributes | Watercourse name, flow direction, gradient, primary flow, TOID® reference, EA or SEPA catchment name and ID |
Scale | 1:1250 – 1:10 000 |
Update frequency | Quarterly - April, July, October, January |
Supply | Download – You’ll need geographic information (GIS) software to use the data. |
Coverage | National |
Support documentation |