This post is a version of the article "How To Protect Your Asphalt Pavement From Water Damage" which will be featured in the December 2014/January 2015 issue of Building Management Hawaii.
Water is one of the main causes of asphalt pavement degradation and can lead to cracks, potholes, and base course failures. The longer water is allowed to pond on top of your pavement or seep into the pavement itself, the worse your problem will become.
The good news is that there are ways to prevent water damage to your asphalt. The following tasks are pillars of pavement maintenance.
Seal Coating
seal coating is a proactive approach to pavement maintenance. A sealcoat is a thin layer of liquid applied on top of an asphalt surface.
The sealcoat fills voids and protects your asphalt pavement from
- oxidation
- chemicals
- water penetration
We recommend sealing asphalt once every three to five years.
It is important to remember that a sealcoat only maintains the current condition of your asphalt. It will not correct structural issues. If your asphalt is in good condition, a sealcoat will help to keep the pavement strong. However, if your base course is failing and is in poor condition, a sealcoat is not suitable and will not fix structural issues with your base.
Crack Filling
Oxidation of your asphalt causes pavement to become brittle. When your pavement is brittle, it is more susceptible to cracking under vehicle loading. Furthermore, once the pavement has cracks, water has a way in. If water reaches the base, your pavement’s ability to carry traffic load is weakened as the water softens compaction. This can result in more cracks; thus, repeating the cycle.
Crack filling will prevent water penetration and should be performed as soon as possible.
There are two types of crack fill: cold pour and hot melt.
While applying cold pour crack fill is less labor and equipment intensive, hot melt crack fill is more pliable, adheres better to the cracks, and sets quicker—which allows vehicles to drive over the area sooner.
Pothole Repair
Potholes usually form as a result of a damaged base course and oxidized pavement. Oxidation causes aggregates in asphalt to loosen and unravel while a water-damaged base course can lead to depressions in pavement. With the addition of vehicles passing over the damaged area, aggregates are displaced and more potholes are created. Potholes will then allow water to continually enter your base course, repeating the cycle.
There are many pothole repair products available.
While most off-the-shelf products from hardware stores are relatively cheap, they do not last very long. You’ll likely find yourself “repairing” the same pothole every few months. At GP Maintenance Solutions, we use a pothole patch material that can last over a year.
However, pothole patches and repair products simply fill holes.
A pothole is the result of a base course that has failed due to water damage. To repair a damaged base course, the area would need to be dug up, replaced with new asphalt, and re-compacted. It would be best to contact a contractor if you wanted to take this action.
It is crucial to the longevity of your asphalt pavement that you protect it from water damage. While most property managers will have budgeted for repaving, consider having your pavement evaluated. An evaluation will help you determine if your pavement even needs to be repaved in the first place. If it does not, you could then reallocate your budget towards waterproofing tasks such as seal coating, crack filling, and pothole repair. Preventing water damage in the first place will delay the need for repaving.
Cole is the Manager of GP Maintenance Solutions. He’s been involved in the asphalt paving/maintenance industry since 2006 and has experience in both estimating and project management for City, State, Federal, and Private projects. Connect with Cole on LinkedIn.