Why is a new pressure reduction installation needed?

Pressure reduction installations (PRIs) help to control and regulate the flows of gas and need to be located at strategic points to ensure the country’s gas network operates efficiently and economically.

National Grid first applied for planning permission to build a new PRI on a site at Corse, immediately west of the existing Tirley above ground installation (AGI), in April 2006. The application was refused by Forest of Dean District Council.

The council’s decision was upheld following an appeal in 2007, but the Planning Inspectors and the Secretaries of State agreed that there is a need to connect a new PRI to the existing gas network at Tirley AGI. 

Site selection process

Following this decision, we have been carrying out an extensive evaluation of potential sites for the PRI within a 10km radius of Tirley AGI.  So far this has narrowed the number of potential sites for the new PRI to two, at either Flat Farm, off the B4213 to the east of Tirley AGI or to the west of Tirley AGI, on the northern side of the B4211.

Consultation and planning permission

Discussions have involved and are continuing with planning officers from the relevant local authorities within the 10km radius, to discuss and seek feedback on the site evaluation criteria, the process and the findings.

In late summer 2008 we are holding public exhibitions to inform the local people about all aspects of the proposed PRI and, wherever possible, to take on board their views.  Following completion of the consultation exercise, a decision will be taken as to which site to apply for planning permission for from the relevant local planning authority.

Construction

The methods used to construct the PRI are based on best industry practice, which includes plans to manage the effects of noise, dust and construction traffic on local communities and roads.  The early creation of earth bunding will help to minimise noise from the site for nearby properties and passers-by.  Additional measures to protect the environment are put in place, such as works to manage groundwater run-off from the temporary construction site. 

Construction of the PRI will take approximately 12 months.

Safety

Safety is a top priority for National Grid and we have an exemplary safety record.  Great Britain’s high-pressure National Gas Transmission System has been in operation for more than 35 years, and has never experienced a serious incident affecting life or property – the means by which safety performance is normally defined.

PRIs and their associated pipelines are designed, constructed and operated to the most exacting safety standards set out by the Institute of Gas Engineers and Managers and approved by the Health and Safety Executive.  Pressure vessels and pipes are constructed using high grade steel, and undergo rigorous testing before commissioning.

Once constructed, the PRI is an extremely safe and secure installation, protected from interference by a series of fences and security systems.

Minimising our impact on the community

National Grid takes its responsibilities to local communities seriously.  We are committed to working with local people to minimise the impact of our works wherever possible.