Storm Drains and Ditches

The Federally mandated Clean Water Act and the County's National Pollutant Discharge Elimination System Permit require all construction projects within Los Angeles County's jurisdiction to implement the appropriate stormwater pollution control measures.

There are stormwater pollution control requirements for road, sewer, water, grading, erosion control, and storm drain construction.

The City of Diamond Bar's Public Works Department is responsible for installing and maintaining storm drains and drainage ditches in public areas and along city roads. Storm drains and ditches divert water and debris from road surfaces after a storm or shower. 

Citizens are reminded to never dispose of leaves, grass clippings, trash, motor oil or chlorinated water into the drainage system or in a location, such as a roadway, where debris could be swept into the system by storm water. Such actions may result in ocean and stream contamination or in serious flooding after the next storm.