Skip to content

GIS improves Wiltshire flood management

Wiltshire have combined local knowledge with Ordnance Survey mapping to analyse local flood impacts and risks in Dauntsey Parish.


Combining local knowledge with Ordnance Survey (OS) digital maps to undertake a professional analysis of local flood impacts and risks.

  • Dauntsey in north Wiltshire has experienced serious flooding, affecting as many as 44 homes.
  • Using Geographic Information Systems (GIS) and digital mapping, the Parish Council can produce accurate and professional looking maps to better track the impact of serious flooding.
  • Initially, they negotiated a sub-contractor licence from their principal authority, which provided access to OS data. This case study explains exactly how they use the data.

The logistical challenges

Following serious flooding, this small Parish, with a population of 532, concluded that it needed to act.

However, it faced a number of challenges: 

  • The Parish was told that the main flood risk concerns were in nearby towns like Malmesbury and Chippenham.
  • It needed to engage the Environment Agency, Highways Agency and principal local authority to influence how they maintained the water courses, culverts and drains in the area to mitigate against this happening again in future.


The solution

Using its Public Sector Mapping Agreement (PSMA) licence from Ordnance Survey (managed using open source QGIS software) the Parish Council was able to establish that more homes had been affected in the Dauntsey Parish than anywhere else in the county.

Creating digital maps also helped to illustrate the extent of serious flooding and allowed all drains, culverts and minor water courses to be marked up online.

The capacity of these waterways could also be inputted, allowing problems to be predicted. Plus, information showing which body was responsible for maintaining each waterway meant work could be prioritised.

"The GIS made us a very strong player. It’s bringing empowerment down to the parish level. There’s no way we could have done this without the PSMA data."
Andrew Chapman, Councillor, Dauntsey Parish Council.

The data driven benefits

  • The Parish Council’s use of professional looking maps meant that its evidence on flooding was taken more seriously.
  • The GIS analysis has assisted affected households in pursing their flooding compensation claims.
  • They could receive and share geographic data with the other statutory organisations.
  • They were able to analyse local water courses and flood impacts across its area.
  • As a result the Highways Agency has significantly altered its maintenance programme by bringing in annual inspections and improved maintenance contracts.
  • The Parish Council now works more closely with the Wiltshire Council maintenance team, which is saving both time and effort.

Useful links

Daunstey Paris Council 


From 1 April 2020, the Public Sector Mapping Agreement (PSMA), was superseded by the Public Sector Geospatial Agreement (PSGA).

1:25 000 Scale Colour Raster

The digital alternative to our popular OS Explorer paper map series, this is a high-quality map of Great Britain, available in 10km square tiles.

1:250 000 Scale Colour Raster

Get the regional view of towns and villages, roads and places of interest.

1:50 000 Scale Colour Raster

The digital alternative to our popular OS Landranger paper map series, this is a high-quality map of Great Britain, available in 20km square tiles.

OS VectorMap District

OS VectorMap® District is an open basemap to overlay and visualise your own information on.