Residential Roadway Maintenance


Area 7 Residential and Collector Street and Diamond Bar Boulevard Street Rehabilitation Project

Update December 16, 2019 - Starting the week of December 16 paving and slurry work will commence on Diamond Bar Boulevard from Mountain Laurel Way to Clear Creek Canyon Drive. Intermittent lane closures will be in effect, motorists are asked to find alternate routes if possible and proceed with caution during construction.

Project Schedule

Residential Area 7 - October 2019 - November 2019
Diamond Bar Boulevard - November 2019 - December 2019

Project Location

Starting October 1, 2019, COPP Contracting, Inc. will be completing street improvements in the Area 7 neighborhood and portions of Diamond Bar Boulevard from Mountain Laurel Way to Clear Creek Canyon Drive.

Project Description

The roadway repair includes asphalt repairs, cape seal, slurry seal, asphalt overlay, crack seal, concrete work and striping.

During the project, street parking will be restricted between the hours of 7 a.m. to 5 p.m. Monday through Friday when construction is being performed. Signs indicating “NO PARKING” will be posted a minimum of 48 hours in advance of the parking restrictions and affected residences will receive additional notices prior to closures.


For project details or issues, contact the Public Works Department at (909) 839-7040 or the COPP Contracting at (714) 522-7754

About Annual Roadway Maintenance Program 

The city is divided into 7 separate Slurry Seal Areas. The areas are rotated each year to receive a slurry seal application and/or a chip seal overlay.

Slurry Seal is a mixture of well-graded fine aggregate, mineral filler and slow setting asphalt emulsion. It is used for both preventive and routine maintenance.

Construction work hours will be from 7 a.m. to 5 p.m. Monday through Friday. The City and contractors will work to minimize the impact to traffic. However, it will be necessary at times to close streets temporarily for a few hours of the day. Please DO not drive through the wet slurry. Slurry is wet when it is laid and will take approximately two to four hours to cure. Streets will re-open the same day once the slurry is cured. Residents will be notified when vehicular and pedestrian access to their property will be disrupted.