Chip and Seal Program

During the summer months, Transportation Maintenance performs a procedure on residential streets called "Chip and Seal". This preventative maintenance procedure rejuvenates old asphalt and creates a new riding surface. Chip and seal reduces the number of potholes and other types of pavement deterioration and extends the life of the street. The cost of this type of resurfacing is approximately one-third of the cost of traditional asphalt overlay. Asphalt overlay is applied to streets approximately every 15 years on a rotating basis.

Crews prepare streets for chip and seal by applying an asphalt crack filling material as well as selectively paving sections of streets. The first phase of the chip and seal is called "chipping" and consists of spraying a thin layer of liquid asphalt onto the road surface, then immediately applying a layer of crushed rock which binds to the asphalt. This phase takes approximately one day. You can drive on this surface within 15 minutes of applying the chips to the liquid asphalt. After approximately two to three days, the street is swept to pick up loose rock.

The second phase of chip and seal occurs approximately two weeks after the chipping is completed and consists of spraying another thin layer of liquid asphalt on top of the chips. This process is called "fogging" and results in a more traditional black street color. The fog coat takes approximately two to three hours to dry. The fog coating seals the street and helps prevent water from permeating into the chips and subsurface. Two to three days after the fogging your street will again be swept to pick up any remaining chips.

Cul-de-sacs do not receive a chip and seal treatment as it is not the best treatment for these areas. Usually, cul-de-sacs receive an asphalt overlay, if maintenance is needed. Cul-de-sacs in good condition usually receive a fog coat only.

After the chipping is done, drive slowly to avoid kicking up any loose rock and asphalt. Driving less than five mph will help prevent asphalt from getting on the finish of your vehicle. Bicyclists should use caution to avoid slipping on loose materials while the application is curing. It is best to stay off the newly chipped surface for one day to avoid tracking asphalt onto driveways and sidewalks and staining concrete.

If you get asphalt on your vehicle and it has not set, water will rinse it off. If the asphalt has set, most common automotive hand cleaners will take it off. These types of cleaners should also be effective on clothes, carpet, or furniture. Please check cleaner labels for any restrictions. If chip and seal gets on vehicle tires, it will come off with driving.

Crews will post signs in your neighborhood 72 hours before chip and seal work is to be done. The process is weather dependent, so please expect delays if there is inclement weather (rain, high humidity, cool temperatures or surface moisture). No on-street parking will be allowed while crews are working. Vehicles not removed from the street during the times posted will be towed at the owners expense.

Last Updated on Monday, 17 April 2006 04:18