VISTRY GROUP – KINGSTON PRISON

Introduction
We were approached by the Vistry Group to undertake several utility surveys due to the high volume of services they were striking on site. Multiple surveys have now been completed to reduce the risk of such instances occurring.

Locations include:
Kingston Prison – Portsmouth
Longhedge – Salisbury
Whiteley Meadows – Whiteley
Deepcut Barracks – Surrey
Boorley Green – Southampton
Hatchwood Mill – Winnersh
Shinfield Meadows – Wokingham

Scope of works
State of the art survey equipment is used on site, this includes; electromagnetic locators, multi-antenna GPR, GPS and total stations to locate and map existing services whose exact location cannot be identified or is unknown.

As-laid surveys were also undertaken as utilities were installed. These were either located using the same techniques listed above or when the services were visible in the trenches before being backfilled.

Uses
Prior to construction, the surveys were used by designers to avoid excavation around existing services and to create new service routes by connecting to existing utilities. An as-laid survey is provided to site operatives to avoid striking services when further excavation is required. Drawings were provided in DWG and PDF format for easy use to anyone who required access to the information. These drawings were also provided to the utility companies to update their records.

Outcomes
According to a report by the University of Birmingham and other sources, the average cost of a service strike (taking into consideration: direct, social and indirect costs) is approximately £29,000. However, Fibre Optic cables are very expensive and so the true cost of a strike could be £80,000 plus. As Fibre Optic cables become more frequently deployed and assimilated into modern day society, construction companies are susceptible to larger monetary losses for each service strike if insufficient survey work is carried out.

By affiliating with Encompass Surveys, the reduction in the number of strikes has led to the employee responsible within Vistry receiving a company award for outstanding contribution to the business.