Abstract: An apparatus for conserving utilities including coolant, in a system having an evaporative cooler equipped with a water reservoir for holding a predetermined amount of cooling water and also equipped with a recirculating system for recirculating the cooling water. The apparatus has a level sensing assembly coupled to the water reservoir. The level sensing assembly provides a first signal when the cooling water level is less than a first predetermined limit. The system has a controller coupled to the level sensing assembly for receiving the first signal. The system also has a supply valve coupled to the water reservoir, to a water supply and to the controller. The supply valve is responsive to signals from the controller. The supply valve delivers water from the water supply to the water reservoir. The system further has a bleed valve coupled to the water reservoir and to the controller. The bleed valve is responsive to signals from the controller.