Water line disinfection and testing continues in an area of Mountain View that lost service after a pipeline breach three weeks ago, the city said Friday.

Water samples taken near home meters in the affected area came back clear of bacteria, but traces continued to be found at a fire hydrant, the city said. The hydrant was disconnected from the system as testing continues.

About 67 households in the 600 block of Cuesta Drive and 600-700 block of Leona Lane lost drinking water service when contaminated cement slurry came into contact with a live water main during maintenance on April 24.

A water main break in Mountain View on April 24, 2026, disrupted service in the Cuesta Park neighborhood. Residents in at least 67 households are now under a boil-water order after contamination was detected in parts of the system, city officials said.
(City of Mountain View via Bay City News)

Twenty-one homes north of Cuesta Park remain under boil water restrictions, according to the city.

On Thursday, the city used multiple foam devices known as “pigs” to scrub out any foreign matter in the pipe along Drucilla Drive and Carla Court. A “super chlorination” treatment was conducted Friday to disinfect the line.

The process of pipe disinfection, reconnection, testing, assessment, and coordination with the State Water Board is expected to take three to five days, the city said.

Mountain View continues to provide temporary shower access to the residents affected by the water main incident. The shower facilities are located at the Rengstorff Park Aquatics Center and El Camino YMCA.

The city is also providing temporary lodging with several hotels.