“Missouri City is not the only city that experienced a rash of back flow valve thefts in September. In Sugar Land, 16 of the year’s 23 cases occurred last month. Back flow valves are connected to sprinkler systems to prevent tainted water from back flowing into the good water system.
…Missouri City police said earlier this week that many times there are witnesses to the thefts, but the witness doesn’t realize a crime is occurring. In Missouri City, 13 businesses were targeted in September. The valves contain copper, which is sold by thieves to scrap metal companies or to individuals. Missouri City police have identified a suspect, described as a white or Hispanic man in a white pickup truck. The suspect had a large “T” handle water shut-off tool and he would shut off the water then knock the brass valve off the PVC piping that it was attached to, put the valve into his truck and leave….”
Source: http://www.fortbendnow.com/2010/10/21/48514