Outside drain unblocker: What to do before water floods your patio

If you're searching for an outside drain unblocker, chances are you're already dealing with a patio that’s turning into a puddle. Blocked outside drains can go from a minor annoyance to a full-blown emergency in no time, especially during heavy rain. 

Whether it’s leaves, mud, grease, or a collapsed pipe, you need to act fast before water floods your garden, patio, or even seeps indoors. This guide walks you through what to do immediately, what tools can help, and when to call FS Group, your trusted outside drain unblocker experts for emergency callouts across London, Essex, Hertfordshire, and Kent.

Step 1: Spot the warning signs early

Outside drain problems rarely appear out of nowhere. Most start with small signs you might easily overlook. Maybe the water takes longer to disappear after it rains. Maybe you’ve noticed a musty smell around your patio. Or maybe there’s a gurgling sound coming from the gully when you run water indoors.

These are all early signs that your outside drain is beginning to clog. If ignored, it won’t take long before water starts to back up completely, especially after storms.

Step 2: Clear visible debris around the drain

If your outside drain cover is accessible, your first move should be to check for surface-level blockages. Leaves, moss, mud, and food waste often collect around gully drains and restrict water flow.

Using gloves, remove anything you can safely reach. Even a small pile of soggy leaves or garden waste can stop water from draining properly. If water immediately begins to flow away after clearing it, the blockage may have been local and superficial.

But if it’s still not draining, or the water’s rising quickly, you’ll need to take the next step and reach deeper.

Step 3: Try a basic outside drain unblocker tool

If you’ve ruled out surface debris and the drain is still blocked, it’s time to use a proper outside drain unblocker. The safest place to start is with a drain rod. These flexible tools help you push through blockages a little further down the system, and they’re widely available at DIY shops.

Some people also try enzyme-based drain cleaners. These biological unblockers are safer than chemical ones and can break down organic matter like grease or food waste over time.

However, avoid harsh chemical solutions. They can damage pipes, especially older ones, and won’t do much if the blockage is caused by tree roots, mud, or collapsed pipework.

If, after trying this, the drain is still full, you’ve likely hit a deeper issue that needs professional help.

Step 4: Call a professional outside drain unblocker

There’s no shame in calling an expert, especially when dealing with outdoor drainage, which is exposed to the elements and can be unpredictable.

At FS Group, we deal with emergencies like this every day. Our engineers arrive within hours, equipped with everything needed to fix the issue: drain rods, high-pressure jetting tools, and advanced CCTV inspection cameras. We’ll identify the cause and sort it on the spot.

Here’s when you should stop trying and call us:

• The drain water is rising and not moving at all
• You can’t locate the blockage
• There’s a strong smell or bubbling from other pipes indoors
• You’ve already tried rods or cleaners without success

A blocked outside drain might look simple, but if it’s linked to your main drainage system, it can cause backflow into your home or business. We’ve seen it happen, and we’re here to prevent it.

Step 5: Understand what’s blocking your outside drain

It helps to know what caused the blockage in the first place. Outside drains are more exposed than indoor pipes, so the causes vary. Some of the most common include:

• Fallen leaves, mud, or moss buildup (especially after storms)
• Grease or fat from kitchen waste
• Non-flushable materials like wipes or hygiene products
• Tree roots growing into joints or cracks
• A collapsed or damaged section of pipe underground

Our engineers can confirm the cause using a CCTV survey. That way, your outside drain unblocker is not just fixing the symptom, but helping you solve the actual problem.

Step 6: Prevent future drain emergencies

Once your outside drain is flowing freely again, it’s worth putting a few simple habits in place to avoid going through the same hassle again. Drainage emergencies are always stressful, but most of them are preventable with a bit of regular care.

Start by keeping the area around your drain clear. Fallen leaves, garden waste, and moss tend to build up quickly, especially in autumn or after a storm. They’re the most common cause of blockages. Installing a drain screen or gully guard can help stop debris from getting into the system in the first place, making routine clean-up quicker and more effective.

You should also avoid pouring anything down your sink that could solidify or build up over time. Grease, fat, oil, and even coffee grounds can stick to pipe walls and eventually block the flow, especially if they end up in the outside drainage system. Enzyme-based treatments used monthly can help break down small buildups and keep everything flowing smoothly.

Why choose FS Group for outside drain unblocking?

Blocked drains can’t wait. That’s why FS Group is set up for rapid response. Most of our work is on emergency drainage issues, including blocked outside drains, gullies, stormwater systems, and more.

Here’s why our customers trust us:

• Fast emergency response—often within 2 hours
• Available 24/7, 365 days a year
• Fully equipped vans with jetting and CCTV gear
• Transparent pricing with free phone estimates
• Coverage across London, Essex, Hertfordshire, and Kent

We’re not here to upsell, we’re here to solve. One call and we’ll take care of it.

Final thoughts

A blocked outside drain can turn into a flooded patio in a matter of hours, especially during a storm. If you’re already seeing signs of trouble, or if water’s rising and not going anywhere, it’s time to call for an outside drain unblocker.

Contact FS Group on 0800 689 3497 or book online for emergency outside drain unblocker support near you. We’ll get things flowing again, fast.