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Can You Run a Downspout Under the Sidewalk?

Can You Run a Downspout Under the Sidewalk?
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It’s important to direct water away from your home. You need to have a proper drainage system so that water doesn’t pool in various spots.

People install gutters and downspouts on their homes to help. Gutters direct water toward the downspout, and the downspout leads the water away from the house.

The downspout generally directs the water toward some type of storm drain. This is a great way to keep water from pooling and damaging your roof or other parts of your home.

You might have an issue directing the water to the drain if you have a sidewalk in the way, though. What should you do about this?

Can you make the downspout go underneath the sidewalk? Continue reading to learn more about this topic and other related questions.

How to Run Downspout Under Sidewalk

You can dig a hole to run a downspout underneath the sidewalk if you want to. It sounds a bit easier than it actually is, though.

This is something that you need to do right or the results won’t be good. Sometimes it’s tough to dig the hole due to the type of soil that is present.

For example, hard types of soil such as clay will be tougher to work with. Rocky soil will also be problematic.

That isn’t to say that it can’t be done when you have rocky soil or clay soil. It’s simply easier for professionals to handle the task since they have the right equipment as well as the knowledge to do the job.

You need to watch out for the thickness of the sidewalk as well. Not all sidewalks have the same thickness, so it might be worth confirming how thick the sidewalk is by taking measurements ahead of time.

To start the process of running a downspout under a sidewalk, you need to install the downspout. You can get what you need from a hardware store.

You install the pipe, couplings, elbows, and everything else that you need to make the downspout work. When this is done, you need to dig a trench so you can run the downspout underneath the sidewalk and point it toward the storm drain.

Digging the Trench

Digging the trench isn’t something that you want to take lightly. Doing this right is important.

It’s best to use wood stakes to figure out exactly where you want the trench to go. Use something such as chalk or powder to make a trail from one stake to the other so that you can visually see where the downspout is going to run.

With this done, it’s time to dig the trench. Dig out the dirt and make sure that your trench has a slight downward slope.

Do your best to dig the trench so that it’s ten inches deep and six inches wide. This should be perfect for the downspout.

You can dig the trench by hand using a shovel, but it might take a bit of time. Depending on the type of soil that you’re working with, it might be a bit time-consuming.

Some people choose to make the process easier by utilizing trenching machines. You could also use a backhoe to get the job done, but this requires finesse and skill.

Running the downspout under the trench involves cutting the end of a PVC pipe at a 45-degree angle and then using a mallet. The mallet is used to chisel the pipe through and get it to the other end of the sidewalk.

Most find this to be the simplest method. Some people use water pressure to shove the pipe through to the other end, though.

This can be done with a hose, but it’s best to use a pressure washer. To get the job done, you’ll need an adapter to connect the pipe to the hose or pressure washer.

You can choose whichever method sounds the best to you. It’s likely easier to use the pipe chiseling method.

Watch Out for Freezing Issues

Freezing issues can become a huge deal if you aren’t careful. If you live in an area where the temperatures dip below freezing at night, it’s wise to dig the trench deeper than usual.

You don’t want the downspout to freeze during the winter. The best way to prevent this from happening is to dig the trench below the freezing line.

It’s necessary to dig deep to get this job done. You’ll need to run the downspout somewhere between 32 and 48 inches below the ground.

If your downspout is connected to a drain well or a pipe, it’s wise to take this step. It’ll protect you from problems with freezing.

The Finishing Touches

Once the downspout is in place, you need to finish up. Install the rest of the pipe and make sure that it’s directed toward the drain.

You need to dig a shallow hole that’s fairly wide at the end of your trench. This hole should be lined with a four-inch layer of gravel.

The end of the pipe should rest on the gravel. Cover the pipe with more gravel once you’ve positioned it properly.

Now you must fill the trenches with dirt. You can use a hoe to move the dirt into the right positions to fill the trenches properly.

Can You Put a Downspout Over a Sidewalk?

It’s generally not the best idea to put a downspout over a sidewalk. Elevated downspouts don’t work out well.

The best thing to do is to use the advice above to dig a trench underneath the sidewalks. This may seem like a tough job, but it’s something that’s manageable.

If you don’t have the time or skills to do the work, you can always hire some help. Local experts can come out to your home to help you with this issue.

You can have people dig the trench for you and install the downspout properly. This is the easiest route to take if you’re someone who works a lot and doesn’t have a lot of spare time.

Can You Drain Water Over a Sidewalk?

Draining water over a sidewalk is generally not the best idea. Once again, you’re simply better off going under the sidewalk.

If you go right over the top of the sidewalk, the water isn’t likely going to flow toward the drain as well. You want to use gravity to make the water go where it needs to go.

Going over the sidewalk makes things a lot tougher. There are some drain designs that you might be able to utilize, but it’s likely going to be impractical.

Keep in mind that the sidewalks are meant to be used for walking. In many cases, the sidewalks are city property, so you might not be allowed to obstruct them with a pipe that leads to a drain.

Even if digging a trench sounds like a huge pain to you, it simply isn’t wise to try to go over the sidewalk. You might even get in trouble for doing so.

Downspout Under Patio

You might need to relocate the downspout if it’s directly underneath the patio. Sometimes adding a new patio will make you need to change how your downspouts are set up.

The water that is being guided away from the house shouldn’t end up spilling out onto the patio. This is going to cause you problems eventually.

Instead, it’s better to install the downspouts somewhere safe. You want them to guide the water toward drains or flower beds that are away from patios, decks, and other such things.

This might take a bit of work depending on where your downspouts are located currently. Regardless, it’s worthwhile since you need to make sure to protect your home from water damage.

Letting the water pool on your patio isn’t a good idea. Technically, you could dig a downspout trench to go under the patio if you really had to.

The concept is pretty much the same as making a downspout go underneath a sidewalk. However, it could be tougher due to the patio being a much longer area.

Final Thoughts

You’ve learned a lot about downspouts and how to run them underneath sidewalks. This is important information that will help you to get good results.

If you follow the advice above well, you shouldn’t have a problem running a downspout underneath your sidewalk. It’ll take a bit of effort, but you can get the job done with patience.

Those who don’t have the right tools or abilities might want to find someone to hire. While it isn’t impossible for a novice to do this job, some people find it to be a bit frustrating.

Either way, you want to ensure that the job gets done well. The downspout needs to direct the water toward a drain or another suitable area.

You don’t want water to pool on your roof or near the foundation of your home. It’s not good for water to pool on your patio or near your deck either.

Do what you must to put downspouts in the right places. In some cases, you might need multiple downspouts if you have issues with standing water during heavy storms.