Water quality in the City of Houston is managed by following the life cycle of a raindrop. Depending on where that raindrop falls it either enters the storm water system or a body of surface water that leads to Lake Houston. If the drop becomes part of Lake Houston it will be taken to the water treatment plant operated by the Drinking Water Operations side of Public Works and Engineering Department (PWE). Once the water is treated, residents of the city use it for watering lawns, washing dishes, drinking, taking showers, and more. The water then returns to the treatment system. If the water falls into the storm water system then the storm water management group of PWE follows it.
The water quality of Houston's bayous, tributaries, lakes and other bodies of water is fluctuates with the rain events. When it rains in Houston the large amount of impervious cover combined with low elevation makes the city prone to flooding. Floodwater washes whatever may be on the ground into the storm sewer system. Contaminants found in floodwaters include oil, pesticides, and sediment. Houston's Storm Water Management Program takes care of ensuring safe water quality.
Water Quality Resources