Palo Alto tap water has been milky in appearance for two weeks, thanks to a change in the distribution system, but the water is safe to drink, city officials say.
However, at least one resident has reported an ammonia smell and taste to the tap water, too.
Water officials at the San Francisco Public Utilities Commission, which oversees the Hetch Hetchy system Palo Alto is part of, and Palo Alto water officials reported no water quality problems on Monday.
The milky color is due to air bubbles in the water, according to the San Francisco PUC, and is expected to last until February.
The Hetch Hetchy system is undergoing maintenance and Palo Alto and other cities on the system are now receiving water from local reservoirs instead of directly from the Hetch Hetchy system in the Sierra Nevada Mountains.
The air bubbles are a result of treatment at the PUC's Sunol Valley Water Treatment Plant.
If the water is left standing, the cloudy appearance will dissipate in a few minutes.