Abstract: An adjustable timing system controlled by a water meter indicator activates an electric shut-off valve at a main water supply to a building or apartment unit if a continuous flow of water exceeds the time setting. The timing system may optionally be set to a full open condition bypassing the timing function and allowing unrestricted water flow or an off condition preventing any water flow. The timing system is reset to begin anew timing the continuous flow of water each time that flow ceases and may be manually reset after a continuous flow of water has exceeded the time setting or a power interruption has disabled the water flow.