How to Unblock Your Stormwater Drain: 5 Repair Tips
Blocked stormwater drains can lead to serious problems, from backyard flooding to costly property damage. Luckily, many drain blockages are easy to fix with the right tools and a little DIY know-how.
Whether your drain is clogged with leaves, dirt or other debris, it’s important to act fast before the situation gets worse. In this guide, we’ll cover five simple and effective tips to help you unblock your stormwater drain and keep things flowing smoothly.
These methods range from clearing surface debris to using more advanced tools like drain snakes and high-pressure hoses. While some issues can be solved with a DIY approach, others may require professional help. Read on to learn how you can tackle stormwater drain blockages and prevent future problems.
1. Identify the Location of the Blockage
The first step to unblocking your stormwater drain is figuring out where the blockage is. This helps you determine the best method to clear it. Start by inspecting the most accessible parts of the system, like gutters, downpipes, and drain grates.
Often, debris like leaves, dirt and sticks accumulate near the surface, causing water to back up. You can use a garden hose or bucket of water to test the flow. If water is slow to drain or pools in one area, it’s a sign of a clog nearby.
If the blockage isn’t visible or easy to reach, it might be deeper in the pipes. In this case, you can try using a plumber’s snake or drain camera for a closer look.
Identifying the blockage’s location early on will save time and effort when it comes to choosing the right unblocking method. Remember, if the blockage is severe or too deep to handle yourself, you may need to call in a professional.
2. Clear Surface Debris
One of the easiest ways to unblock your stormwater drain is by clearing any surface debris that’s obstructing the flow of water. Leaves, dirt, and twigs can quickly accumulate around drain grates and downpipes, leading to blockages.
Here’s how to tackle the problem step-by-step:
- Inspect gutters and drain grates: Check the areas around your stormwater drains, particularly the grates and downpipes, for visible debris. These are common spots where leaves and dirt collect.
- Use a rake or your hands: Carefully remove leaves, branches, and other debris by hand or with a garden rake. Wear gloves to protect your hands from sharp objects.
- Dispose of the debris properly: Avoid pushing it down the drain as it may worsen the blockage. Instead, collect the debris and add it to your compost or green waste bin.
- Rinse the area with water: After clearing the visible debris, flush the area with water to ensure the drain is clear and functioning properly.
Regularly clearing surface debris can prevent future blockages and keep your stormwater drains working efficiently.

3. Use a Drain Snake for Blockages
When surface debris isn’t the issue, and the blockage is deeper in the pipe, using a drain snake can be an effective solution. A drain snake, also known as a plumber’s auger, is a handy tool designed to reach blockages that are out of sight. Here’s how to use it:
- Choose the right snake: Drain snakes come in different sizes. For stormwater drains, a medium-sized snake should do the trick. You can find these at most hardware stores.
- Insert the snake into the drain: Slowly feed the snake into the drainpipe until you encounter resistance. This likely indicates that you’ve hit the blockage.
- Rotate the snake: Turn the handle to rotate the snake, breaking up or hooking the debris. Keep twisting until you feel the blockage loosening.
- Pull out the debris: Once the blockage feels like it’s been broken up, carefully pull the snake out of the drain, bringing the debris with it.
- Rinse with water: After clearing the blockage, flush the drain with water to ensure everything flows smoothly.
Using a drain snake is an easy, effective way to clear tough clogs without needing professional help.
4. Flush the Drain with High-Pressure Water
If your stormwater drain is still clogged after clearing surface debris, it’s time to try flushing it with high-pressure water. This method is great for dislodging blockages that are deeper in the pipes, like built-up mud, leaves or other debris. You can use a garden hose with a high-pressure nozzle or, for more stubborn clogs, rent a pressure washer.
Insert the hose into the drain and direct the water toward the blockage, applying firm pressure. The force of the water can help break up and flush out the obstruction, allowing the water to flow freely again.
Be cautious not to overdo it with the pressure, as you don’t want to damage your pipes, especially if they’re older. If you’re unsure or the blockage doesn’t budge, consider hiring a professional who has the proper equipment for the job, like a hydro jet drain cleaner. Flushing the drain with high-pressure water is often a quick and effective way to clear blockages and restore proper drainage.
5. Check for Structural Damage
If clearing debris and using tools like a drain snake haven’t solved the problem, your stormwater drain may have structural damage. Cracks, collapsed pipes, or misaligned joints can cause persistent blockages.
Here’s what to look for:
- Inspect for cracks or leaks: Walk along the drainpipes and check for any visible cracks, leaks, or areas where water is escaping. These can be signs of damage in the system.
- Look for sinkholes or water pooling: If you notice unusual depressions in the ground or areas where water is pooling, it could mean a section of the pipe has collapsed or shifted.
- Test the water flow: Run water through the drain and observe if it’s flowing normally. Slow or inconsistent flow, even after clearing debris, could indicate a more serious structural issue.
- Call a professional for an inspection: If you suspect significant damage, it’s best to call a professional plumber. They can use specialised tools like CCTV drain cameras to assess the extent of the damage and recommend repair or replacement options.
Identifying structural damage early can prevent bigger problems down the line and save on costly repairs.

Get Your Drains Flowing Again
Unblocking a stormwater drain doesn’t have to be overwhelming. With the right tools and techniques, you can often clear blockages and get your drains working smoothly again.
From clearing surface debris to using a drain snake or high-pressure water, there are several effective DIY methods to try. However, it’s important to know when the problem might be more serious, like structural damage, and when to call in a professional.
Regular maintenance, like cleaning out leaves and debris, can also help prevent blockages from happening in the first place. By taking action early, you can avoid costly damage and keep your stormwater drains in top shape. If in doubt, don’t hesitate to get expert help for more complex issues.
Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See Cyber Plumbers’ Terms & Conditions here.