Keeping valves operable and accessible and maintaining fire hydrants are essential components of water system maintenance. Based on recommended industry practices and standards, the preventive maintenance and system updating program at the St. Louis, Missouri County Water Company is described. Maintenance of valves includes marking valve boxes and recording their location, wrapping all underground iron with polyethylene to prevent corrosion, replacing old valves, operating all valves that are 400 mm or larger yearly, and properly training employees who work with and monitor valve operations. Fire hydrants are similarly maintained, with emphasis on proper training of all city personnel who are authorized to operate hydrants and annual operational maintenance programs. Includes 7 references.