 About 140,000 people in Glasgow were affected – they were told not to drink tap water without boiling it first.In the early 2000s, security at the facility was tightened with large metal screens being erected around areas of both Mugdock and Craigmaddie Reservoirs, believed to be an action taken in line with the Ministry of Defence's security policy after the September 11 Attacks.The fences and security cameras remained in place for many years, which led to public annoyance at the unnecessary and impractical screens.