How To Fix Potholes In A Gravel Driveway

Potholes In Your Gravel Driveway?

As a homeowner with a gravel driveway, you know all too well the annoyance of potholes. Not only do they look unsightly, but they can also cause damage to your car, create safety hazards for anyone who walks or drives on your property, and hey… even spill your coffee, darn it!

Fortunately, repairing potholes in a gravel driveway is a DIY project that can be done with some basic supplies and a little bit of guidance.

In this post, we’ll show you how to fix potholes in a gravel driveway by walking you through each step. Estimating the quantity of materials needed to make the repairs, gathering the necessary materials, and follow our repair process. We’ll also talk about strategies for preventing potholes from forming and maintaining a smooth and strong gravel driveway. So whether you’re a seasoned DIY-er or a newbie to home repairs, this guide will help you fix potholes in your gravel driveway and enjoy a more functional, safe, and attractive outdoor space.

Pothole Repair Steps

Identifying the Cause

It’s important to identify what caused the potholes in the first place. Is it soft and unstable subgrade? Is it simply a low spot in the driveway that was filled with water from the last rain or snow that became a larger pothole from driving on it over and over? Is it a combination of both? Understanding the cause of the potholes can help determine how you’ll go about the repairs you’ll need to perform.

Proper Diagnosis is Essential

Properly diagnosing the issue is key to an effective and long-lasting repair. If the cause of the potholes is due to soft and unstable subgrade, you’ll likely need to excavate those areas and add a strong base material to strengthen them before completing the surface repair. If the cause was a low spot that was filled with water from the last rain or snow, you may need to grade the driveway in order to redirect water flow, making sure that water does not stand on the surface of the driveway. If the cause is a combination of both, then both types of repairs will be needed. Without properly diagnosing the issue, you may end up wasting time and resources on a repair that won’t last.

Identifying Soft And Unstable Subgrade

The quickest and least expensive way to identify unstable subgrade is by manually doing it yourself. A key indication of soft and unstable subgrade is that the bottom of the pothole is very muddy and mushy when it’s wet. Also, if you see the subgrade move when a heavy vehicle drives over the general area. A loaded dump truck will usually point out unstable areas the fastest.

On the other hand, hiring a geotechnical engineer is the best way to determine unstable subgrade, but can be very expensive. However, look at it this way. If someday you plan on installing concrete, asphalt, or pavers on your driveway, every bit of time and money you invest in your gravel driveway at this stage is an investment into the future.

Estimating Total Sq Ft Needing Repairs

The next step is estimating the total size of all of the potholes combined. Take a walk around your driveway and use a tape measure and/or measuring wheel to measure the size and depth of each pothole. Write or type the size of each pothole, Length x Width x Depth, so that you can later estimate the quantities of materials you’ll need to purchase for the repairs.

Yes, I know potholes are generally round and not square, but you don’t need to be a math whiz and get overcomplicated about it. Just measure as close as you can. Here’s an image to show you how I measure potholes.

Once you’ve finished measuring each pothole, now it’s time to figure the quantity of materials you’ll need to fix them.

Estimating The Materials You’ll Need

Base Material For Unstable Subgrade

Now when it comes to estimating the quantity of base material you’ll need for unstable subgrade, I want you to understand that I know this can be a difficult aspect of the DIY pothole repair process. But I also want you to know how to do it because, if you’re looking for a permanent repair of potholes in your gravel driveway, this is how it’s done when the subgrade is unstable.

One of the unfortunate parts of excavating unstable subgrade, or “de-mucking” as it’s referred to in the construction world, is that you never know really how deep the unstable subgrade goes. I’ve seen it run as deep as 3′ feet. So this too can complicate the de-mucking process as a DYI’er. But knowing how to do this will also help you if you decide to hire a gravel driveway pro to do it for you instead.

So the best way to do this as a DYI’er is to dig out the unstable material, under one pothole, until you hit stable subgrade. Then measure the depth, less the surface material.

In other words, if your gravel material on the surface is 3″ inches in depth and the depth of your hole is 12″ inches, then the amount of base material you’ll need is 9″ inches. 12″ inches in depth, minus 3″ inches of surface material (gravel) = 9″ inches.

From this point, just assume the remaining potholes are going to be roughly the same depth of 9″. This may or may not be the case, but you have to start somewhere. Some may be deeper than others. Some less.

So let’s say, for example, you’ve figured a total of 600 Sq Ft of potholes with the unstable subgrade. Knowing your depth is 9″ inches after you’ve excavated the unstable subgrade, you’ll need to calculate the amount of base you’ll need to fill those areas back in and compact the material.

Here’s a link to a great calculator that can help you determine the amount of base you’ll need.

Based on this calculator, using Limestone base and crusher run, the amount of material you’ll need is 31.1 Tons.

Surface Material

The best way to determine the amount of gravel, or surface material you’ll need is to dig out the remaining surface material in a square, around one pothole. Then measure the depth. Also, if the area where the pothole is low and/or flat, to obtain the desired sloping to help facilitate water running off of the area, you’ll need to add more material to your depth measurement.

In other words, if your gravel material on the surface is 3″ inches in depth and the depth but the area is low by 2″ inches for example, then the amount of base material you’ll need is 5″ inches. 3″ inches in depth, plus 2″ inches of additional surface material (gravel) to get the water to run off = 5″ inches.

From this point, just assume the remaining potholes or surface material is going to be roughly the same depth of 5″ inches.

For example, you’ve figured a total of 600 Sq Ft of potholes. Knowing your depth is approximately 5″ inches, you’ll need to calculate the amount of surface material you’ll need to fill those areas back in, and compact the material.

Here’s a link to a great calculator that can help you determine the amount of surface material you’ll need.

Based on this calculator, using Traprock coarse aggregates, the amount of material you’ll need is 12.8 Tons.

Where To Purchase Materials

Once you’ve determined the number of materials you’ll need to repair your potholes, now you’ll need to find a bulk supplier that you can purchase them from.

Most bulk suppliers have delivery options unless, of course, you have the means to haul the materials yourself. If not, and they don’t deliver, they can usually refer you to someone that can.

Doing an online search for “rock supplier near me” should yield several results.

Gathering The Necessary Tools

For Repairing Surface Materials

Before you can start repairing potholes in your driveway, gather the necessary tools and supplies. Common tools needed for the repair include a shovel, rake, hand tamper (or for the best results, a jumping jack or plate compactor), and a wheelbarrow.

It is also important to wear protective gear, such as gloves, eye protection, and steel-toe boots to keep you safe while undertaking these tasks.

For “Demucking” or Repairing Unstable Subgrade

To demuck the subgrade, you’ll need several essential tools and possibly some heavy equipment depending on the size of the job. These include a shovel, a wheelbarrow, a rake, and a jumping jack or plate compactor. Jumping jacks or plate compactors are especially important as they increase the density of the sub-grade material, creating a solid foundation that will hold up against the weight of cars and other vehicles.

For larger jobs, you’ll likely need a backhoe or skid steer to dig out the unstable material. A backhoe will be much easier and more effective. You’ll also quite possibly need a dump truck to haul the excavated material and dispose of it. I can tell you this, if you can find a place to leave the excavated material on your property, you’ll be far better off. It can be very difficult to find places that will take soil due to environmental contamination concerns. Sometimes you may find other homeowners looking for topsoil or fill dirt if you search Facebook Marketplace or Craiglist.

It is also important to wear protective gear, such as gloves, eye protection, and steel-toe boots to keep you safe while undertaking these tasks.

Excavating The Unstable Subgrade

Excavating the unstable subgrade can be a challenging process, but it’s necessary to ensure the stability of your gravel driveway. By taking the time to do the job properly, you can achieve a stable and secure subgrade that will support your driveway traffic for years to come.

To excavate the unstable subgrade, you can use shovels or a backhoe, although a backhoe is much faster and easier. It’s important to remove all of the soft material until you reach a hard layer of soil or a change in the color of the subgrade material. Keep in mind that the depth of the excavation will depend on the extent of the instability. There’s no exact way to determine how deep or wide the unstable subgrade is, so be sure to also go by visual assessment to determine when you’ve hit more stable subgrade.

Repairing The Demucked Areas

Now that you’ve demucked the soft areas, you’re now left with gaping holes. So of course, you’re probably wondering how to backfill them properly. Backfilling is an important step in the demucking process. Let’s talk about how to do that!

Base Installation – Step-by-Step Instructions

1. Start by adding about 3″ inches of base material to the excavated hole.
2. Use a rake to spread the base material evenly over the surface of the hole.
3. Compact the first layer of base material using a jumping jack, plate compactor, or hand tamper. This will help to ensure that the material is tightly packed and level. The more compaction you get, the more solid your repair, hence why I recommend a jumping jack first, then a plate compactor (plate compactors are hard to get in and out of a deep hole).
4. Add another 3″ inch layer of base material, spreading it evenly over the previous layer. It’s important to add the base material in layers rather than all at once, as this will allow for better compaction and a more stable subgrade.
5. Continue adding layers of base material, compacting each layer as you go. Add more material until the hole is filled just beneath the level of your surface material
   

Surface Layer Installation – Step-by-Step Instructions

• Use the same type of surface material that was originally used for your driveway. This will ensure that the repair blends in seamlessly with the surrounding gravel.
• Make sure to add the surface material in layers rather than all at once. Then compact each layer thoroughly using a jumping jack, plate compactor, or hand tamper. This will allow for much better compaction.
• Dampen the surface material before compacting it. A damp material will compact better, allowing for a more stable repair.
• Consider applying a layer of fines, such as gravel dust, over the repaired area to improve the appearance and help stabilize the base material.
  

Summary

In conclusion, maintaining a gravel driveway is important for safety and aesthetic reasons… and well… to keep from spilling your coffee!

Identifying the cause of the pothole, and properly backfilling the hole to stabilize the subgrade is essential to ensuring a long-lasting and effective repair.

To repair a pothole in a gravel driveway, you’ll need to gather the necessary materials, follow the steps for properly estimating quantities and diagnosing the issue, as well as invest in some basic tools such as a shovel, rake, and compactors.

Properly filling the holes left from demucking is also an essential step.

By following the tips and instructions provided in this blog post, you’ll be well on your way to a safe, functional, and visually appealing gravel driveway that can stand the test of time.