A $20 plumbing oversight can become a several-thousand-dollar repair surprisingly quickly.

That's particularly true in Minnesota, where outdoor plumbing spends months exposed to freezing temperatures. Early September may seem too soon to think about frozen pipes, but it's actually a good time for rental-property owners to identify exterior plumbing problems while there's still plenty of time to correct them.

The objective isn't to winterize everything today. It's to make sure you know what needs to be winterized and whether it actually works.

Start With Every Exterior Faucet

Walk around the property and locate every exterior faucet.

That sounds obvious, but on older Twin Cities homes I've seen hose bibbs hidden behind shrubs, beneath decks and on additions where owners didn't realize another water connection existed.

Turn each one on. Does it operate normally? Does it leak around the stem? Can you determine where its interior shutoff is located?

If it's a conventional sillcock rather than a properly installed frost-resistant model, you'll generally need to shut off the interior valve and drain the exterior section before freezing weather.

And regardless of faucet type, disconnect the garden hose.

Leaving a hose attached can prevent water from draining properly from some frost-resistant faucets, defeating the reason the faucet was installed in the first place.

Know Where the Shutoffs Are

Fall is also a good time to locate and label water shutoffs.

If an exterior faucet begins leaking—or a pipe freezes in January—you don't want the first step to be searching through a finished basement trying to determine which valve controls it.

Operate older valves carefully. A shutoff that hasn't moved in 15 years may not work when you actually need it.

For rental properties, I like the idea of having these locations documented. A few photos stored with the property's maintenance records can save considerable time during an emergency.

Don't Forget Irrigation Systems

Automatic irrigation deserves separate attention.

University of Minnesota Extension notes that many Minnesota irrigation systems need to be drained before the ground freezes, which typically occurs during the third or fourth week of October across much of Minnesota. Extension also recommends giving lawns and perennial plants adequate water before freeze-up when conditions are dry. University of Minnesota Extension

That doesn't mean September 1 is necessarily the day to shut the irrigation system down.

In fact, doing it too early can deprive landscaping of useful fall watering.

Instead, now is the time to schedule the winterization, inspect damaged sprinkler heads and determine whether the system has developed leaks during the summer.

Pay Attention to Backflow Protection

Irrigation systems and exterior hose connections introduce another issue owners sometimes overlook: backflow.

Backflow occurs when contaminated water can potentially be drawn backward into the potable water supply. The Minnesota Department of Health recommends appropriate backflow-prevention devices on threaded exterior faucets and specifically notes that homeowners concerned about freezing can use drainable models. Minnesota Department of Health

This is an area where it's important to distinguish maintenance advice from plumbing-code requirements.

Minnesota's Plumbing Code regulates water-supply systems and backflow prevention statewide. Plumbing alterations and installations must comply with that code, and businesses contracting to perform plumbing work generally must be appropriately licensed. MN Labor and Industry

So if you're changing plumbing rather than simply performing routine seasonal maintenance, use a qualified professional and determine whether a permit or inspection is required.

Check the Places Water Enters the Building

While you're walking the exterior, look beyond the faucets.

Where does the irrigation piping enter the house?

Where does the main water service enter?

Are there pipes running through an unheated garage, crawlspace or unusually cold portion of the basement?

If you've purchased the property recently, don't assume the previous owner winterized everything correctly simply because there wasn't a problem last year.

Minnesota houses can be remarkably forgiving—until we get several consecutive nights well below zero.

The Best Emergency Repair Is the One You Never Need

Property management involves plenty of emergencies that can't reasonably be predicted.

A tree falls. An appliance suddenly fails. A sewer backs up.

Frozen exterior plumbing usually isn't in that category.

We know winter is coming. We know which parts of a house are vulnerable. And we have several weeks right now to do something about them.

That's why September is such a valuable maintenance month in Minnesota.

Don't wait until the forecast says 25 degrees to start wondering where the exterior-water shutoff is.

Find it now.

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