It's a fact: we all hate potholes. They're impassable, they can damage your car, and they don't discriminate. The longer potholes are left unrepaired, the larger they become and the more costly they are to repair. In Minneapolis, the peak pothole season is from late February to late March early April. But what causes potholes? How do you prevent them? And how do you fix them once they appear?
There are multiple ways potholes are formed, ranging from poor workmanship, defective materials, not sealcoating your driveway, end of life of asphalt and water. Water is the primary culprit for potholes. When the asphalt and the subbase cannot support the weight of traffic is the main reason potholes are formed. Cracks in the asphalt are where rain and melting snow enter and works its way down to the base. The base and soil beneath become saturated and soft.
Freeze-Thaw cycles cause the base and soil to expand and traffic weakens the asphalt, causing it to crack more. When the temperature rises, there is a void under the pavement allowing for more water to penetrate the base and soil. This process repeats multiple times, with each time the void becomes larger and larger.
As cars continue to drive over the weakened pavement pounding on the pavement until it finally gives way, and we have the birth of a pothole.
To prevent potholes, you need to prevent water from entering the base of your parking lot. An asphalt maintenance plan will help you prioritize repairs and keep you up to date on preventative maintenance. A paving company can help you develop an plan
Sealcoating your parking lot every 2-3 years will help fill hairline surface cracks, helping to prevent them from growing into larger cracks. Also, sealcoating will slow down the oxidization of the asphalt, keeping it pliable and less prone to cracking.
Annual crack sealing with professional-grade sealant should also be part of your maintenance plan.
Finally, even the smallest of holes in your parking lot should be addressed. A 4" hole can turn into a 2' hole in a short period of time. Deferring maintenance will put you on the path to more expensive repairs in the future.
There are many ways to repair potholes, but there 3 main ways we deal with them in Minnesota. Each method has a specific application and corresponding pros and cons.
Commonly called "Throw and Roll" and "Throw and Go" cold patches are not a long-term fix. Cold mix asphalt is used to fill the pothole and depending on the hole, its either compacted with a roller or its left "as is" and cars rolling over it will compact the patch.
Cold patches are a great short-term fix if you have a larger hole in a high-traffic area. However, they should not be considered a permeant solution.
Hot Patches are more labor and equipment-intensive, meaning each repair will cost more. However, a hot patch provides a more uniform repair and should last the remaining life of your parking lot.
The repair area is saw-cut into a rectangle. The repair area might be subjectively large because we need to cut back to sound pavement. The patch area is removed of water and debris. Tack (bonding agent) is applied to vertical sides to hold the new asphalt in place. The patch area is filled with asphalt and then compacted with either a vibrating compactor or roller.
Infrared asphalt repair are an excellent option for pothole repairs and there are a few paving companies in St. Francis that can help with this repair. This process is long-lasting, less disruptive and has lower repair costs. Additionally, the repairs are seamless resisting water and ice intrusion. Infrared asphalt repair is green because the existing asphalt is used and doesn't have to be hauled to the dump.
The hole is cleared of debris and then a heating unit is placed over the repair area. The heating unit will soften up the existing asphalt. Using a rake, an operator will loosen up the existing asphalt. Additional asphalt will be added to bring the patch to the proper grade. The patch will be compacted with a roller.
The patching process takes 20-40 minutes per patch so there is minimal downtime. Infrared creates a thermal bond which makes the patched area very strong and will last life of your parking lot.
The average depth of a pothole is 12 inches deep.
Potholes are not limited to cold climates.
January 15th is National Pothole Day
The word "pothole" has some folklore dating back to the Romans. It has been said "potters" took clay from the Roman roads to make clay pots. However, Roman roads were mainly made from stone. The term became commonly used by American drivers in 1909.
In Hennepin County, you can report potholes here.
On Minnesota maintained roads you can report potholes here.
Potholes are part of the reality of owning a parking lot in Minnesota. A prevent asphalt maintenance plan is your first line of defense and when there is an issue contact us, the leading sealcoating company in Princeton so we can help fix the problem before it becomes costly. Also, while concrete is stronger than asphalt its not uncommon to find potholes in concrete driveways either.