Interserve plc is a multinational support service and construction company based in the UK. Groundwork GDS has worked with Interserve on numerous projects, helping them understand how their operations affect the social, economic and environmental features of the areas they work in.

Our Projects

Travel Time catchments

n GIS, ‘proximity’ to a location is measured in straight lines (euclidean distance or distance ‘as the crow flies’). Using a simple buffer analysis, common proximity questions like - suppliers located within 25 miles of a construction site or stores within 5 miles of a postcode – can be answered. An alternative approach is to derive the catchment (service areas) reachable by different transport modes (walk / driving a car / public transport) using road network models. Compared to the buffer analysis, this approach is more complex and requires up-to-date transport network data and software extensions to implement in desktop GIS. Although subscription services are available from various vendors, accessing this across different GIS platforms can be challenging.


As most of the modern day commuting from place A to B involves multiple modes of transport, this can add an additional layer of complexity in catchment mapping. When choosing a location in terms of access, it is more often sensible to use the time it takes to reach by common transport modes rather than the distance. It is all the more powerful when public transport timetables are also integrated within the travel time estimation. Traveltime Platform offers an API which allows travel time catchment calculation using a combination of travel modes for the entire UK.


Our prototype application uses the Traveltime Platform API to generate the travel catchments which are saved as geojson in a PostgreSQL database and are then converted to PostGIS geometry objects using ST_Transform, ST_SetDRID and ST_GeomFromGeoJSON constructors. Using this approach, travel catchments can be created on the fly which will be available for spatial analysis in the desktop as well as online environments.

Social Impact Assessment

Groundwork GDS has been working with Interserve over the years to help them understand the value of their business to the community using geospatial tools. Due to the vast spread of their operations across the country, the social value from any particular contact/relationship needs to be assessed based on the location of its supply chains, employees and underlying socio-economic fabric of the local community. Interserve understands the importance of spatial analysis and mapping of baseline statistics for the development of this tool and Groundwork GDS with many years of experience in the mapping and analysis of large scale socio-economic and location data are in a strong position to contribute to this partnership.

A summary of the findings from the assessment can be found here.


Groundwork - Geospatial & Data service

Groundwork GDS is part of Groundwork London