Drinking Water Aesthetics -Taste, Odor and Color
The change in the taste, odor, and color of Houston’s drinking water that is sourced from wells is caused by naturally occurring compounds and minerals such as hydrogen sulfide, sulfur, iron, and manganese. The City of Houston’s main water system receives approximately 15% of its water from several wells and groundwater plants across the service area. During times of high water use in the City’s system, the percentage of well water that is used can increase as the City turns on more wells to keep up with the higher usage. This can change the water aesthetic characteristics from typical conditions.
The change in the taste and smell of Houston’s drinking water that is sourced from reservoirs is caused by byproducts of a naturally occurring algae bloom in our lakes called geosmin and MIB (2-methyl isoborneol). Houston’s main drinking water system receives approximately 85% of its water from the San Jacinto River (Lake Conroe & Lake Houston) and the Trinity River (Lake Livingston). Lakes often see an increase in naturally occurring reactions such as algae blooms when there is warmth and direct sunlight. Occasionally, sudden changes in temperature and rainfall can also initiate these types of events.
FAQ - Taste, Odor and Color Concerns in Drinking Water
Geosmin and MIB are naturally-occurring compounds that are present in reservoirs and are not harmful, but can give the water a musty, earthy, or fishy taste and smell.
The City’s drinking water continues to meet or exceed ALL Federal and State standards and is SAFE. Water professionals routinely monitor and test the water as part of meeting these standards.
Algae blooms that can be a cause of rise in MIB and Geosmin levels are a seasonal event. Since geosmin and MIB are naturally-occurring, they will diminish with time and weather changes
Some reports indicate that chilling the water and or adding fruit slices may assist with the taste and odor differences. Additionally, home water filtration systems that contain carbon may also provide some assistance.
As the effect of the seasonal changes diminish and the water aesthetics return to typical characteristics, customers may choose to perform a flush inside their private property water infrastructure such as tanks and water heaters to facilitate taste and odor returning to typical conditions.
These naturally occurring compounds and are not harmful, however, can give water a taste and odor that is typically described as “rotten egg”.
Some reports indicate that aerating may assist with some of these taste and odor concerns. Additionally, home water filtration systems that are designed for compounds typically encountered with well water may also provide some assistance. As the City’s water usage returns to typical levels, customers may choose to perform a flush of their private property water infrastructure such as tanks and water heaters to facilitate taste, odor, and color returning to typical conditions. The City performs routine testing for several parameters in the water supply system. Please see https://www.houstonpublicworks.org/drinking-water-quality-report
These naturally occurring compounds have secondary standard recommended levels, are monitored for exceedance, and are not harmful within the typically monitored levels found in the City’s water supply. These compounds can give water a metallic taste, can cause color variations in the red, yellow, and black spectrum, and can cause stains. The City performs routine testing for several parameters in the water supply system. Please see https://www.houstonpublicworks.org/drinking-water-quality-report
The City performs routine testing for several parameters in the water supply system. Please see https://www.houstonpublicworks.org/drinking-water-quality-report
Some reports indicate that aerating may assist with some of these taste, odor, and color concerns. Additionally, home water filtration systems that are designed for compounds typically encountered with well water may also provide some assistance. As the City’s water usage returns to typical levels, customers may choose to perform a flush of their private property water infrastructure such as tanks and water heaters to facilitate taste, odor, and color returning to typical conditions.
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
Taste, smell, and odor changes are typically the result of seasonal and naturally occurring processes, and are not safety concerns. However, the City does performs routine flushing of water lines in order to keep the taste, smell, and look of the water within typical parameters so that customers do not experience a significant change to these parameters.
During times of high water use, the percentage of well water increases and customers may notice a significant change to the taste, odor, and color aesthetic characteristics of their water.
As the City’s water usage returns to typical levels, customers may choose to perform a flush of their private property water infrastructure such as tanks and water heaters to facilitate taste, odor, and color returning to typical conditions.
FAQ - Water Line Flushing
The City routinely flushes water as part of regulatory standards and also for best management practices. These flushing activities of water lines ensures circulation of fresh water throughout the system. Flushing can also occur as part of the routine procedures for new, replacement, or repair of water assets.
FAQ - Pressure Concerns
Water pressure at a given location can fluctuate due to a variety of reasons, including new construction projects, increased usage by existing customers, new users, operations and maintenance activities, leaks, and fire-fighting activities. The City of Houston’s water infrastructure system is a vast and interconnected network of approximately 7,600 miles of water lines, 170,000 valves, and 62,000 fire hydrants across the approximately 650 square mile service area.
The City provides a minimum of 35 psi (pounds per square inch) during normal operating conditions, and 20 psi during emergency conditions. The public water supply pressure is measured upstream of meters, and typically at fire hydrants. The water pressure that the customer will experience inside their private property premise plumbing, which is downstream of the public supply, will be less than the pressure that the City provides as there is pressure loss as water travels across appurtenances such as meters, backflow preventors, bends, offsets, and elevations. Customers who wish to have higher pressure than what the City can deliver should consult with appropriate water and plumbing professionals to explore private-side pressure boosting improvements to their facilities. The City does not control nor do we enter private property to measure pressure downstream of the meter.
Water pressure at a given location can fluctuate due to a variety of reasons, including new construction projects, increased usage by existing customers, new users, operations and maintenance activities, leaks, and fire-fighting activities.
The City provides a minimum of 35 psi (pounds per square inch) during normal operating conditions, and 20 psi during emergency conditions. The public water supply pressure is measured upstream of meters, and typically at fire hydrants. The water pressure that the customer will experience inside their private property premise plumbing, which is downstream of the public supply, will be less than the pressure that the City provides as there is pressure loss as water travels across appurtenances such as meters, backflow preventors, bends, offsets, and elevations. Customers who wish to have higher pressure than what the City can deliver should consult with appropriate water and plumbing professionals to explore private-side pressure boosting improvements to their facilities. The City does not control nor do we enter private property to measure pressure downstream of the meter.
For concerns about City infrastructure, including concerns about pressure, please call 311. A ticket will be generated and staff will investigate by taking the pressure at the nearest public asset to the location, which is typically a fire hydrant. If the pressure is believed to be low for the area, a valve sweep will be conducted to ensure all valves are open for the area.
The City provides a minimum of 35 psi (pounds per square inch) during normal operating conditions, and 20 psi during emergency conditions. The public water supply pressure is measured upstream of meters, and typically at fire hydrants. The water pressure that the customer will experience inside their private property premise plumbing, which is downstream of the public supply, will be less than the pressure that the City provides as there is pressure loss as water travels across appurtenances such as meters, backflow preventors, bends, offsets, and elevations. Customers who wish to have higher pressure than what the City can deliver should consult with appropriate water and plumbing professionals to explore private-side pressure boosting improvements to their facilities. The City does not control nor do we enter private property to measure pressure downstream of the meter.
FAQ - Water Supply
The City of Houston’s main system water supply is approximately 85% surface water and 15% well water. Currently, customers on the east side of the City typically have a mix that is higher in surface water and customers on the west side of the City have a mix that higher in well water. Because the City’s system is interconnected, these ratios cannot be known for any given specific area. The City’s service area also includes some areas that are outside of the main system, largely around the Lake Houston area, that are served exclusively by well water.
The City has scoped several projects, currently in different phases, that will increase the use and availability of surface water throughout the entire City service area.
For a highlight of some on-going projects, please see: Houston Public Works (engagehouston.org)