Pavement Management

Dump truck and chip spreader demonstrating chip seal process


Pavement management, or road maintenance, is an essential function of Jefferson County Public Works. Jefferson County’s roads require continuous maintenance in order to preserve them for a longer life. A combination of private contractors and County crews are used to meet the County’s road maintenance needs. Properly planned pavement maintenance and repair help extend the life of existing pavement. Through the County’s Pavement Management program the County visually inspects every major roadway once every three years and local streets once every five years to assess their condition and determine where pavement maintenance is needed. Some common road maintenance approaches are:

•   Pothole Repair

The County has over 518 lane miles of paved roads to maintain. Phone calls emails from our landowners and residents in pinpointing new potholes are always welcome and appreciated.

Crews patch potholes with at hotbox in the back of one of the trucks on a periodic basis. Once a pothole has been spotted or reported, it’s the goal of Public Works to repair it as soon as possible (preferably within 24 hours), weather and resources permitting.

Potholes can occur any time during the year but tend to occur most often during and after the winter season, especially when there is more precipitation and changing temperatures. Pavement expands and contracts during extreme hot and cold spells. This allows water to get under the pavement and leads to potholes. Snow plows and heavy traffic can also increase the occurrence of potholes.  Our road crew works year round to patch potholes, including during the winter when they aren’t driving snow plows, but especially when pavement temperatures are above freezing and not wet.

To report a pothole, please call Jefferson County Public Works with a specific location. Your report will be logged and sent to the crew for response.

•   Crack Sealing

Crack Sealing involves using a polymer modified liquid asphalt substance to seal cracks of the roadway. This is Jefferson County’s first line of defense in pavement preservation. Sealing the cracks reduces the infiltration of water and subsequent roadway damage from freezing and thawing.

  • Asphalt Overlay

Another form of road maintenance is sometimes referred to as “asphalt overlay”.  Once asphalt has been laid, it can be driven on almost immediately. However, drivers are asked to watch for and respect the detour requests of flaggers as road workers put the final touches on the road, such as smoothing it out and achieving density with heavy double drum road rollers.

The benefits of asphalt are durability, cost effectiveness, smoothness and the ability to install it relatively quickly”, said Matt Powlison Public Works Director for Jefferson County. “It is also a recyclable asset”.

  • Mill and Overlay

Another form of road maintenance is sometimes referred to as “mill and overlay”. This process consists of two major steps:

  • Milling the road surface
  • Laying the new asphalt (overlay).

To mill the road, workers use heavy equipment to remove a couple inches of the surface of the road and place it into dump trucks. Workers then use a machine to spray “tack,” a liquid asphalt coating that will assist in adhering “bonding” the new asphalt to the road. The final process is overlay, which is shorthand for laying a new lift of asphalt on the road.

Once asphalt has been laid and compacted, it can be driven on almost immediately. However, drivers are asked to watch for and respect the detour requests of flaggers as road workers put the final touches on the road, such as smoothing it out with heavy double drum rollers.

Milling and overlaying a road is about five times more expensive than other options such as chip sealing, but about five to 10 times less costly than full roadway reconstruction.

“The purpose of the road maintenance program is to focus on a workable and affordable plan for improving the integrity and service life of County roads over the long term, while reducing the costs associated with deferred maintenance”, said Powlison.

  • Chip Seal

Each year Jefferson County Public Works uses a variety of proven approaches to pave, patch or preserve our County roads. Chip sealing is by far the most cost effective method of road maintenance.

Our goal is to extend the life of our roadways in the most cost effective and least disruptive manner possible”, Director Powlison said. “The approach for each road is based on our resources such as budget, personnel, and the condition of each road”.

Jefferson County’s roadways are rated on a 100-point scale with a rating of 100 indicating “new/excellent” condition. Roadways with a rating of 1 have “totally failed” and require reconstruction (very expensive). Typically, an asphalt roadway with a rating of 70-80, or “good condition,” is the best candidate for a chip seal. The objective is to preserve the underlying roadway structure at a relatively low cost.

The average overall network Pavement Condition Index (PCI) of Jefferson County’s road network is 71, which indicates that the road network is in ‘Good’ condition.

How cost-effective is it?

The chip seal process typically costs $3-$4 per square yard. By comparison, milling off the road surface and putting down a new overlay of asphalt costs between $15 and $20 per square yard. This means that a typical 1,000-foot residential road would cost $9,000 to chip seal but more than $45,000 to mill and overlay. (Total reconstruction, on the other hand, could range between $350,000 to $500,000 for that same road).

What is chip seal?

Chip sealing uses the same ingredients as asphalt concrete paving, but rather than milling the road and laying down new pavement, a thin film of heated asphalt liquid is sprayed on the road surface, followed by the placement of small “chips” or stones. Rollers then go over the chips to compact and adhere them to the existing asphalt. The excess stone is swept from the surface after a period of time to allow the chips to dry and settle.

What does it do?

The chip seal process is a crucial element of the County’s pavement preservation process. It prevents deterioration by sealing up cracks and providing a pliable long-term wearing surface that can typically last 5-7 years (longer if followed up by a fog seal or other treatment).

With the passage of time and vehicles over the roadway, chip seal tends to self-heal the cracks in the road and protect the pavement from water intrusion (which is the enemy). Excess chips are swept up by street sweepers as soon as the chip seal dries but may need to be addressed several more times after that.

We have been using fog seal treatments to help better lock those chips in place and provide contrast with the striping”, Powlison said. “Road users and landowners have been responding positively to that approach”.

Safety Tips

During chip seal operations, and several days afterwards, drivers are advised to drive more cautiously. The road surface is tender. Please avoid speeding, turning too sharply and spinning tires. Motorcycle riders, please use extreme caution.