# How to Winterize a Rain Barrel Before the First Freeze
> Drain, disconnect, and protect your rain barrel before the first freeze — the steps that keep the barrel and its diverter from cracking over winter.
Canonical: https://www.backyardfreedomlab.com/blog/how-to-winterize-a-rain-barrel/
Published: 2026-09-08
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Every fall, rain barrels crack the same avoidable way: a mouthful of water nobody bothered to drain sat in the bottom through the first hard freeze and had nowhere to go but outward. It is one of the cheapest, most avoidable failures in backyard water collection, and it takes about as long to prevent as it takes to read this article.
**Short answer:** winterizing a rain barrel means draining it completely, disconnecting it from the downspout diverter so runoff bypasses it all winter, cleaning out the sediment before it dries or freezes in place, and either storing the empty barrel indoors or protecting what has to stay outside. None of it costs money. All of it has to happen before the first sustained freeze, not after.
Disclosure: the product links here are affiliate links, so we may earn a commission if you buy through them at no extra cost to you. The freeze-thaw guidance below follows standard manufacturer care instructions and extension-service rainwater-harvesting practice, not any single barrel's marketing.
Almost nothing fails from the cold itself — it fails from the water somebody left standing inside it.
## Why Rain Barrels Actually Crack in Winter
The mechanism is simple physics, not bad luck. Water grows in volume by approximately 9 percent as it freezes, and ice expands with enough force to crack open a plastic rain barrel, especially one that is full or near full ([Penn State Extension](https://extension.psu.edu/rain-barrel-winter-maintenance-dont-forget-to-disconnect)). If there is a puddle of roof runoff — untreated water that is not for drinking, same as anything else your gutters shed ([Penn State Extension](https://extension.psu.edu/rain-barrels-information-and-guide)) — sitting in the bottom of the barrel when a hard freeze hits, that water expands as it turns to ice and pushes against the plastic from the inside. The barrel does not fail gracefully. It splits along whatever seam or corner is weakest.
The same thing happens on a smaller, faster scale inside a downspout diverter. A diverter's internal chamber and valve hold a small amount of water by design, and that water freezes solid well before a full barrel does, because there is less of it insulating itself. A cracked diverter is a cheaper fix than a cracked barrel, but it is the same failure for the same reason.
You don't need to watch the thermometer night by night — you need the water out before your area's typical first hard freeze, before the cold settles in for good.
## What You'll Need
This is a low-cost project. Most of it is tools you already own:
- A garden hose or a few buckets, to run the barrel dry
- A stiff brush for scrubbing out sediment
- A Phillips or flathead screwdriver, depending on how your diverter clamps on
- Pipe insulation or foam wrap, if the spigot has to stay outside
- A breathable tarp or cover — not sealed plastic
- Indoor storage space (shed, garage, basement), if you have it
If your barrel came without a proper spigot or drain-friendly base to begin with, or if this is the year yours finally cracked, a fresh barrel built for the job is worth the modest cost before you're rebuilding the whole setup in spring.
A food-grade barrel with a screened inlet and a bottom spigot — the same anchor piece behind most backyard collection systems, and the easiest thing to replace outright if last winter already got to yours.
## Step 1: Drain the Barrel Completely
Open the spigot all the way and let gravity do the work — run it into a hose headed for the garden, or fill watering cans if you'd rather use the last of the season's water than dump it. Once the visible water is gone, check the bottom. Most barrel spigots sit a little above the true floor, which leaves a collar of water behind even after the spigot runs dry. That collar is exactly the pocket that freezes first and splits the base seam, so tip the barrel on its side or prop up the back edge to pour out what the spigot missed.
If the barrel is still plumbed to a downspout diverter, expect a little more water to arrive on the next rain even after you think you're done — which is your cue to move to disconnecting it.
## Step 2: Disconnect the Diverter and Restore the Straight Downspout
Pull the flexible feed hose or diverter body off the downspout run and reconnect a straight section (or the original elbow) so winter precipitation and snowmelt drain away from your foundation the way the gutter system was designed to before you added a barrel. Utah State University Extension recommends disconnecting and storing barrels for winter in cold climates and notes that a diverter makes that easy ([Utah State University Extension](https://extension.usu.edu/sustainability/research/rain-barrels-in-utah)). Leaving the diverter connected with nowhere for water to go is how you end up with standing water backed up in the fitting itself — the exact setup that cracks a diverter faster than it cracks the barrel.
If you added a first-flush diverter as part of your setup, following our [guide to installing a first-flush diverter](/blog/first-flush-diverter-rain-barrel-how-to/), it needs the same treatment: drain the holding chamber, disconnect it if the kit is designed to come apart, and store the body somewhere it won't sit full of its own runoff all winter.
A diverter kit routes water into the barrel and sends overflow back down the spout — the exact hardware you're pulling now and reinstalling once the freeze risk passes. Worth having a spare on hand if yours has seen a few winters already.
## Step 3: Clean Out Sediment Before It Freezes
A season of roof runoff leaves sediment, pollen, and a thin algae film on the bottom and walls of the barrel. Rinse it with a hose and knock the film loose with a stiff brush before it dries into a crust or, worse, freezes solid inside a barrel you've decided to leave outside. Penn State Extension also calls winter a good time to replace worn drain valves, torn screens, or leaky inlet hoses ([Penn State Extension](https://extension.psu.edu/rain-barrel-winter-maintenance-dont-forget-to-disconnect)). A quick scrub now is a two-minute job; scraping frozen sludge out of a barrel in March is not.
## Step 4: Store the Barrel Where the Freeze Can't Reach It
An empty barrel is far more freeze-tolerant than a full one, but it still isn't indestructible plastic — UV exposure and temperature swings take a toll over a winter sitting outside. If you have anywhere indoors — a shed, garage, or basement corner — move it there, either upright on a flat surface or tipped upside down on a couple of blocks so nothing can pool inside from stray moisture. Indoor, empty, and off the ground is the combination that gets a barrel through winter without a mark on it.
## Step 5: Protect Whatever Stays Outside
Not everyone has the storage space, and an outdoor winter is a workable compromise if you take a few precautions. Leave the spigot valve fully open rather than closed — a closed valve traps whatever residual moisture is left in the fitting with nowhere to expand, while an open one lets it drip out instead of splitting the housing. Wrap any exposed spigot threads in pipe insulation or foam, since threaded fittings are thin-walled and crack easily. Cover the top with a breathable tarp rather than sealed plastic sheeting, which traps condensation underneath and invites mold rather than keeping the barrel dry.
## Step 6: Note Your Reconnect Point for Spring
Before you walk away for the season, take a quick photo of how the diverter and hose were routed, or jot a note about which downspout height the diverter clamped onto. It sounds unnecessary in September and saves real frustration in April when you're staring at a straight downspout trying to remember exactly how the pieces went back together. Store any removed diverter hardware indoors as well — cold makes plastic brittle, and hardware that survives a winter in a shed reinstalls a lot easier than hardware that spent it outside.
## Troubleshooting Rain Barrel Winterizing
**The barrel already has a crack from a past winter.** A hairline crack well above the fill line may hold for another season if you keep water below it, but a crack at or near the base seam means the plastic has already flexed and weakened across the panel. Replacing the barrel outright is cheaper than trusting a patch through another freeze-thaw cycle and finding out mid-storm that it didn't hold.
**I can't get the spigot to fully drain.** Sediment buildup at the outlet is the usual cause. Detach the spigot if your barrel allows it and clear the fitting by hand rather than forcing the valve, which can crack the housing you're trying to protect.
**My ground freezes solid under the barrel every year.** That's a drainage issue separate from the barrel itself — water pooling and refreezing under the base usually means the pad it sits on needs better runoff, which is worth fixing in spring before the barrel goes back.
**I forgot to winterize and the first freeze already happened.** Check for cracks before you assume the barrel is fine. If it survived, drain and disconnect it immediately rather than waiting for a second freeze to test its luck twice.
## The Bottom Line
Winterizing a rain barrel is not a project — it is twenty to forty-five minutes of draining, disconnecting, and either storing or protecting what's left, and it costs nothing beyond the pipe insulation if you need it. The physics behind it is simple enough to remember without a checklist: water that's still inside something when it freezes is what breaks that something. Get it out, and the barrel you spent [an afternoon building](/blog/diy-rain-barrel-system/) this spring is still working next spring too.
A rain barrel is only one layer of a backyard water setup, though. If you're running more than one barrel, our guide to [building a multi-barrel rainwater system](/blog/multi-barrel-rainwater-system-budget/) covers the same draining and disconnecting logic across a linked setup, where a missed barrel in the chain causes the same crack for the same reason. And harvested rainwater was never meant to be your only water plan for the year — for the stored, treated water that actually gets a household through an outage, see our guide to [storing emergency water at home](/blog/how-to-store-emergency-water-at-home/).