(October 7) Bacterial contamination has persisted in one of the waterlines at Forestar Canyon Hills’   residential subdivision in Chino Hills, despite previous efforts to cure the problem.
Forestar Canyon Hills is constructing 76 dwelling units on 141 acres off of Carbon Canyon Road nestled against Chino Hills State Park. The land plan is designed around the rolling topography and native oaks and will feature wide angle vistas.
Marring the undertaking, however, is the presence of heterotrophic bacteria in a water pipe at the site. That contamination was first discovered in July when lab tests showed bacteria was proliferating in the water. The city contacted the developer, who then began flushing the line in an attempt to clean it. Water was blasted at a high level of pressure through the line on July 28, July 31, August  1, August 4 and August 5, each time accompanied with chlorinated water to kill the bacteria.
All told, some 750,000 gallons of the bacteria-laced water were flushed from the waterline by the end of the first week of August. Follow–up lab tests of water from the line were conducted and employees with the Chino Hills Public Works Department expressed confidence in August that the remedial action had redressed the situation. In September the waterline was connected to the city of Chino Hill’s full matrix of pipelines.
At that point it was determined that the bacteria yet remained in the water system. Efforts to flush the line were reinitiated, this time on a grander scale than previously. Over the last five weeks, 1.4 million gallons of water were vectored through the line.
While further test results were not available at press time, concern is growing that the bacteria may be seeping into the pipe from some yet undetected crack. Officials have not commented on inquiries as to the possibility of backpressure resulting in the bacteria spreading in general throughout the city water supply.