The City’s water supply comes from a mix of surface water and ground water. There are seasonal naturally occurring algae in the surface water, known as MIB and Geosmin, that can impact the taste and odor of water from earthy to fishy.
There are also natural occurring compounds and minerals in well water such as Hydrogen Sulfide, Sulfur, Iron, and Manganese, that can cause taste, odor, and color differences from typical conditions, ranging from metallic taste, a rotten egg smell, and color differences in the yellow, red, and black spectrum.
Typically, the City’s water supply is largely surface water, however, in times of high water use, the percentage of well water increases and customers may notice differences to the taste, odor, and color aesthetic characteristics of their water.
The City performs routine testing for several parameters in the water supply system. Please see https://www.houstonpublicworks.org/drinking-water-quality-report