The Hatherley Rd/Warden Hill Rd junction in Cheltenham (Photo Rob Wallace).
In July 2007, there was extensive flooding across Gloucestershire. Although this did not threaten the GCHQ sites at Benhall and Oakley directly, it did disrupt the supply of chilled water to both sites that is essential for the running of GCHQ's super-computers. Road tankers were used to bring in supplies over a ten day period, meanwhile GCHQ shut down a number of non-critical systems to reduce demand. The event triggered a "business continuity review" of all the three agencies by the Intelligence and Services Committee, the UK's main oversight body.