Chipsealing is done in many states in the U.S. It is a cost-effective way to maintain roads and saves significant tax dollars. Chipsealing is a yearly process on selected roads that puts a coating over the asphalt of a street to protect it from water and weather damage and to keep the roads in good condition.

During the 2015 chipseal season, ACHD will resurface 500 miles of roadway. The 2015 chipseal season will begin on Monday June 8, 2015 and last until late August.

View a video of Chipsealing Chipseal Process

Chipseal Information:

2015 Chipseal Areas

  • Zone 4

  • In preparation for the chipseal season, ACHD crews perform crack seal maintenance on streets within the chipseal zone. The sealant forms a long-lasting, resilient seal which is flexible and expandable in varying and extreme pavement temperatures. Crack sealing prevents the invasion of surface water between the layers of asphalt and layers of roadway below it. Not all roads that receive a crack seal will receive a chipseal within the same year.

Why Do We Chipseal?

Asphalt deteriorates in time because of the sun and weather. A Chipseal helps seal the surface and provides an armor coat for skid and weather resistance. The best aspect of Chipsealing is simple economics.

In 2009 the cost for chipsealing was $23,000 a mile. Chipsealing saves taxpayer dollars because it protects the road from deterioration and greatly delays the need for a new asphalt overlay to repair a deteriorated road. At this time, asphalt overlays (new blacktop) cost up to $265,000 per mile

Some preparation work will take place throughout the spring, and the chipseal process traditionally begins the first week in June. The work involved consists of four phases: applying the chipseal, sweeping excess chips, applying the fog coat, and microsealing cul-de-sacs. On-street parking will be affected during each phase.

We appreciate your patience during this time, and we realize that while the surface is not very compatible with skates or roller blades, it is still the most economical. For area boundary descriptions for our operations this year, please call 387.6325 at our urban division and 387.6350 for our rural division.

“I’d like to give credit to ACHD for chipsealing our subdivision, they did a beautiful job. They operate like a well oiled machine, and it was hot out there. My wife and I appreciate everything they did," said Ken Weland of Meridian.

Chipsealing Operations

As a part of maintenance program, crews chipseal street surfaces (including new streets) to protect then from water and weather damage and to keep them in good condition.

A Chipseal application to a road or street has many positive objectives:

  • Chipseal to maintain the existing pavement in its present condition by delaying further aging due to water and sun - this is equally important to new streets;
  • Chipseal to change the texture of the road for skid resistance;
  • Chipseal to supply minimal additional strength to the pavement;
  • Chipseal to provide a moisture barrier;
  • Chipseal to give better resistance to studded tires;
  • Chipseal to correct existing pavement problems by sealing cracks.

What is a Chipseal?

A Chipseal is an application of asphalt followed with an aggregate "rock" cover. It is constructed to produce an initial placement or maintain an existing asphalt pavement.

How is it Done?

Prep Work

  • First, the road surface needs to be properly cleaned of debris and any holes patched.

Asphalt Application

  • Next, an asphalt distributor truck starts by shooting only one lane at a time with hot liquid asphalt to assure an even application. The asphalt used is applied at a temperature between 140 and 180 degrees Farenheit. After cooling, this asphalt remains slightly flexible to maintain its hold on the rocks.

Rock Application

  • Another piece of equipment, the chip spreader, follows as rapidly as possible with a rock application, preferably within one minute. The asphalt must be fluid so the rock will be embedded by the displacement of the asphalt. The rocks are an aggregate crushed to a special specification for size and cleanliness.


  • Next, a rubber-tire roller is used to set the rock into the fresh oil. This is done to get the flat sides of the rock down and produce a tighter chipseal. It takes two to four passes of the roller to set the rock.

Second Lane

  • After the first lane has been shot, covered with rock and the rolling has begun, the equipment starts the second lane. The operation is the same as the first shot.


  • Sweeping is done at the completion of the Chipseal process to remove surplus rock from the surface. This loose rock can grind and loosen rock set in the Chipseal and damage the project. Sweeping is done as soon as possible after the asphalt has set up (three to seven days).


  • ACHD follows each Chipseal with a Fogseal that helps set the rock and control fly-rock and dust. Fogsealing also adds life to a Chipseal. This is a separate process that follows sweeping by up to three weeks.


  • ACHD Sealcoats all old and new streets in a neighborhood to save money and prolong street surface life. On residential streets, six years will pass before the Sealcoating process is again necessary.