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The Full Process

How We Clean Buried Downspout Extensions

We use an extensive, and expensive, array of highly specialized tools and nozzles specifically sized and chosen for residential downspout extensions.

Where Do Buried Downspouts Go?

Many homes have downspouts that connect to underground extensions. They should guide rainwater away from the home and end in a clear exit point, usually a 4" cap in the yard. They are very commonly lost. Just a small layer of grass can stop the caps from opening. These lines also catch debris over time, especially shingle gravel.

A clogged or covered line can send hundreds of gallons of water back towards your basement or crawlspace. In most cases we can clear those clogs and return the line to service. Ideally we do this before the disaster as maintenance, but if it's too late for that we can definitely help prevent the next one.

Somehow we ended up knowing a lot about downspout extensions. We're a big hit at parties. If you want the deeper dive, we've put together short articles covering the most common questions at our Learn page.

Technician kneeling to disassemble lower downspout connection
Every downspout connects to a buried pipe at the base.

Why They Need Maintained

Buried downspout drains are very easy to forget about or ignore until there's an issue like a flooded crawl space or basement. Ideally, that is avoided by maintaining these. All that is needed is a cleaning once every three to five years to flush out all of the shingle gravel and other debris that builds up that rainwater just can't wash away.

Here in Indiana in particular, most of us are on such flat land that these drains simply don't have much slope to them. They do require occasional cleaning to stay fully operational. These are the most common issues that form in the downspout extensions we work on.

Large root ball removed from corrugated downspout extension
Shingle granules accumulate in gutters first, then wash into buried drains.

Shingle Gravel (90%+ of Jobs)

Over 90% of homes have asphalt shingle roofs, and every one of them is constantly shedding coarse mineral granules. These granules wash into gutters with every rain, flow through the downspouts, and settle into the corrugated ribs of your buried pipes.

After a few years there's enough of this sandy material that other debris starts getting trapped, and roots start to grow. It takes specialized bits and the right setup to flush all this heavy sediment out without harming the pipe. We commonly remove several pounds of shingle material per line.

Lost Cap

Caps get buried under grass, mulch, or landscaping. Once buried, they can't pop up or drain, and the pipe automatically backs up toward the house and foundation. Any debris that enters, including that gravel, is truly stuck.

In most cases these caps are less than a couple inches deep and simply need to be re-exposed and cleaned, and they'll be fine.

Exposed drain exit with clogged cap
A buried cap can't pop up or drain — it's automatically clogged.
Massive root blockage pulled from buried downspout
Root intrusion at a drain exit — a common discovery during service.

Root Intrusion

Tree and shrub roots seek moisture. These drains don't dump out their contents, they sit and hold water and slowly let it seep away. Combine this with mud or shingle gravel and it's the perfect environment for roots to grow through. Often they simply come in through the exit.

This is how most failures we see occurred; situations where the pipe just had to be fully replaced. Enough sediment sat in the line, which is always damp or wet, and major roots grew unknowingly.

Never had these cleaned before? Not sure where your exits are? We can figure all of that out.

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Downspout Extension Cleaning Process

We have a tried and true process for locating, lightly excavating, and clearing lost or clogged downspout extensions. It's even better as maintenance before a problem is known. This is only an overview, but most services are similar.

Collection of specialized jetting nozzles for residential downspout cleaning
Purpose-built nozzles for different clog types.

Before We Arrive

A few things that help everything go smoothly:

  • Decide which drains to service. We charge per downspout extension, even if multiple share an exit. If you're not doing all of them, mark the ones you'd like cleaned — painter's tape, small flags, or just a note in your booking works great.
  • We'll need water access — a working exterior spigot is all we need.
  • Keep about 20 feet clear around the work area — no people or pets nearby during jetting, just for safety.

None of this is a dealbreaker if you forget. We'll figure it out. But it helps.

Using radio locator to find buried drain cap
Every drain exit located, flagged, and documented.
Step 1

Find All Exit Points

We will locate the exit cap for each downspout extension. When one is not obvious, we have multiple tools to locate it, including a radio locator that we can send in from the downspout side to trace the pipe and pinpoint the end. We will neatly excavate around any hidden caps, usually no more than a couple of inches, and we'll flag them for you.

Step 2

Penetrate Any Clogs

A preliminary pass from the exit back to the downspout will identify any blockages. We have a range of specialized tools to get through these blockages without harming the pipe. We cycle through the necessary bits until the debris is loose enough to come out as one piece (typical for roots) or can be flushed out in the next step.

Jetting nozzle tip working inside corrugated pipe
Specialized nozzle designed for residential corrugated pipe.
Clear water flowing from drain with jetting reel visible
Photo proof of clear water flowing — captured for every drain.
Step 3

Flush and Verify

This is the critical step, where we get rid of shingle gravel or other sediment that really leads to the bigger issues like root systems. Again, we have multiple bits depending on the situation. When we start, we'll see thick debris and very dark muddy water exit immediately. It'll lighten as we continue. We will repeatedly make passes until the water runs clear and the line is able to rocket from end to end without interruption or any feeling of resistance through the jetting line. This is generally the part we photograph — a clean white geyser of water verifying that drain is fully clear.

Step 4

Overview & Photos Emailed

After service, we'll email your invoice with a review of what we saw, what came out, your verification photos, and any recommendations we have. Sometimes we might even be able to quote repairs or upgrades for you. You can review at your convenience and then pay online.

Example verification photo collage sent after downspout jetting service
Every service includes photos, notes, and findings — delivered by email.

See what it costs for your home

Starts at $299 for up to 3 drains · $50 each additional

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