How to Unclog a Downspout: 4 Easy Methods
A clogged downspout makes even a clean gutter overflow. Most clogs sit at the top opening or in the bends (elbows), and you can usually clear them in a few minutes with simple tools.
Find the clog
Run a hose into the gutter by the downspout. If water backs up at the top, the clog is near the opening. If water flows in but barely comes out the bottom, it is lower down, often in an elbow.
Method 1: clear the top by hand
From a safely placed ladder, pull out leaves and twigs sitting in the opening with a gloved hand. Many clogs end here.
Method 2: flush from the bottom
Push a garden hose up into the downspout from the bottom and turn it on full. This often pushes the blockage back up and out the top - stand clear.
Method 3: use a plumber's snake
Feed a hand auger (plumber's snake) into the downspout from the top or bottom and turn it to break up the clog, then flush with water.
Method 4: take the elbows apart
Most downspouts are held by a few screws at the bottom elbow. Remove them, clear the elbow by hand, and refit. Tap along the pipe to find any hard spot first.
Clogged downspout that goes into the ground
Some downspouts feed an underground pipe. Clear the visible downspout first, then flush the buried pipe with a hose from the top, or feed a snake into it. If water still backs up, the buried pipe may be crushed or full of roots - this needs a drainage pro. Many homeowners add a simple above-ground extension or splash block so water drains well away from the house; the US EPA also suggests directing downspouts onto lawns or rain gardens where it is safe.
Stop it happening again
- Fit a downspout strainer or leaf guard at the opening.
- Clean the gutters on schedule (how often).
- Consider gutter guards if you have many trees.
Frequently asked questions
Can I use a pressure washer to unclog a downspout?
From the ground it can help, but never use one from a ladder. A garden hose or a plumber's snake is safer and usually enough.
How do I unclog a downspout without a ladder?
Flush it from the bottom with a hose, use a snake from the bottom, or take off the lower elbow to clear it by hand.
What causes downspouts to clog?
Leaves, twigs, pine needles, seed pods and shingle grit, often packed together at the opening or in the bends.
Should downspouts drain into the ground?
They can drain into an underground pipe, but those pipes clog and are hard to check. Draining onto the surface well away from the house is simpler where space allows.