If your outside drain is overflowing, it means that it us unable to drain. This is caused by clogs, especially during fall when there are lots of leaves lying around, or after a heavy downpour causing mud to block the drain.

An outside drain works just like the sewer drain system. It is gently sloping to drain out water with the help of gravity.
Unlike the sewer drain which is usually clogged by home waste, outside drains are clogged by soil, mud, leaves and other types of debris. The process of unblocking them is therefore slightly different.
To unblock outdoor drains, you can scoop out the clog with your hand, break it down using a drain rod or dislodge it with drain cleaning bladder. If those methods fail, you can rent a drain auger or hydro jetting machine from a plumbing store which are perfect for severe clogs.
The method of choice for unclogging an outdoor drain depends on the severity of the clog, and the type of drainpipe you have. Some pipes are sensitive and cannot be unclogged using some of the methods I have mentioned above.
The 3 types of pipes used for outdoor drains are PVC, corrugated and perforated pipes. PVC pipes as you already know are solid plastic pipes while corrugated pipes have series of ridges and grooves running parallel to each other.
They could be made from iron, steel, PVC or even HDPE. As its name implies, a perforated pipe is a pipe with a series of holes all around it, which are used for draining water.
What I need to say here is that if you have corrugated or perforated outdoor drainpipes, you cannot use a drain auger/snake to unclog it. The auger head has a blade which can get hooked on the ridges or holes of the pipes and tear it apart.
Related: How to unclog a basement floor drain.
How to Unblock an Outside Drain
Although, there are several methods to unclog an outside drain, always start with easiest and fastest and then upgrade gradually when that doesn’t work.
I should also mention that this is not your typical plumbing job. If you need to hire someone to do the job, get a drain cleaning expert but if you must get a plumber make sure that they are experienced in unclogging drains.
As a result, these types of jobs are usually quite expensive to outsource. This is why you should try and do it yourself before hiring an expert.
Unclogging drains is not a glamorous task. You will therefore need to dress appropriately. Get some elbow-length gloves, boots and old preferably waterproof clothes.
The following are the methods to use to unblock an outside drain clogged with mud or filled with soil:
1. Scoop the Clog out with Your Hand
The first thing you need to do however is to remove the drain grate. This is the cover on top of the outside drain.
- Use a long flathead screwdriver to pry it off or even a grate hook to remove a heavy grate. Put it aside to give you room to work with.
- Put on your elbow-length gloves and carefully stick your hand in the drain.
- If there is mud, soil or leaves at the top section of the drain, you will be able to scoop it out.
- Check if the water drains after removing the mud.
- If the clog is deep inside the drain, you will need a better tool for the job.
2. Break Down the Clog with a Drain Rod
Drain Rods are long, thin and flexible tools, usually made with steel joints that you push down drains to break down clogs. They are cheap and easy to use.
The main advantage of drain rods as opposed to the above method is that they are able to reach clogs deep inside the drainpipe and act on them directly. With a drainage rod, you can either connect it with a plunger cup or corkscrew.
While using a plunger you will be trying to push the clog down the drain but with the corkscrew the idea is to break down a solid clog. Some will however only come with a corkscrew which is still alright.
- Start with the plunger connected to the first rod.
- Slowly push it down the drain until you encounter resistance.
- Turn it clockwise to try and dislodge the clog.
- If the clog feels quite solid, pull out the drain rod and go in with the corkscrew attachment.
- See if that gets the job done.
- Dump a bucket of water to see if the drain is unblocked
While using a drain rod, you always want to turn it clockwise. Turning it counterclockwise might loosen the connections and leave some sections inside the drainpipe.
3. Use a Drain Bladder to Dislodge the Clog
Another tool you can use to unblock an outside drain is a drain cleaning bladder, also known as a blow bag. This tool somehow works like a hydro jetting unit only less powerful.
Drain bladders come in different sizes so you will need to choose the right one for you outside drain. This will be between 3 and 6 inches.
- To unclog an outdoor drain with a drain bladder, connect it to your garden hose and push it as far as possible inside the drain.
- Turn on the faucet connected to the hose.
The bladder will fill with water effective sealing around the drainpipe. A tiny hole at the front of the bladder will then open and start shooting a water jet straight at the clog.
If the the clog is not that tough it will break and the drain will open up.
This method may work or fail depending on the severity of the clog. If it fails, you will need to do upgrade to either a drain auger or hydro jetting unit.
4. Snake the Drain
As I had mentioned earlier, only use this method if you have a PVC drainpipe and not perforate or corrugated pipes.
A drain snake/auger has a long flexible cable with a bladed head at the front. It is rolled on a drum and will vary in size. To unclog drains, the cable is turned inside the drainpipe where the head shreds the clog and therefore opens the drain.
Due to the big size of the outdoor drain, you need a big drain snake which you may not readily have at home. I am talking of a snake with a ½ or ¾-inch cable. This means you will need to rent one from a nearby plumbing store.
If you have the ordinary drain auger, you can try to use it before deciding to rent one out. You however cannot use a toilet auger to unblock outdoor drains.
Drain augers are the best tools to unclog drains. They are powerful but if you are not careful you can end up damaging the pipes.
Never force them auger to go past a restriction when the cable starts to twist instead of turn. Pull it up and start turning it again. With time, you will manage to break down the clog.
5. Use a Hydro Jetting Unit

Most people are better of outsourcing this service rather than do it themselves. To start with, you will need to rent out the machine and there is no guarantee that you will use it properly to effectively break the clog.
A professional drain cleaner will however do the job satisfactorily and within no time. It will however not be cheap.
A hydro jetting machine uses water under pressure (water jets) aimed at the clog to break it down. It is usually very successful and will not damage your pipes.
Outside Drain Clogged with Toilet Paper?
Usually, if your outside drain is clogged with toilet paper, it is a sign that there is clog somewhere between the house and the septic tank or city’s sewer line. This causes overflowing of toilet paper via the outdoor drain.
Whenever there is a clog in your main sewer line, toilet paper will float at the top of the water column. Adding more water into the outside drain will result in the toilet paper overflowing.
The clog could be in your property or in the neighborhood’s main sewer line. Unfortunately, this is not a problem most homeowners can fix on their own. You will need to hire a professional drain expert to get to the roof of the problem.
How to Prevent Outdoor Drains from Clogging
Preventing your outdoor drain from clogging is better than having to deal with a clog.
Keeping your yard and other areas of your house clean is the easiest way to prevent clogs. Make sure there are no heaps of soil or leaves lying around, which is what clogs these drains.
You should also frequently remove the drain grate and pull out leaves from the top of the drain using you bare hands. Sticking a garden hose inside the drain also ensures that the drain remains open.
Cleaning drains frequently also helps. Since you do not want to use chemicals, pouring a cup of baking soda followed by vinegar will break whatever gunk that is accumulating inside the drain. Enzyme-based drain cleaners are also fantastic for the job.
And basically that is how to unblock outside drains. If you are unsuccessful on your own, feel free to contact a professional in the field.
These guys have seen the same problem before and therefore know what exactly to do to fix it. They also have the right tools for the job.