Seattle Home Inspector's Blog


When do sump pumps fail?

Just like the rubber hoses on your washing machine, sump pumps are obviously programmed to fail when you are on vacation.

A home that needs a sump pump can suffer a lot of damage if the sump pump fails to operate when needed.

When do sump pumps fail?

Typically they fail when you need them the most.  It will fail (not function) when the power goes out for example.  And when does the power go out?  When the weather is delivering the conditions that make the sump pump necessary to begin with.  Of course seasonal ground water levels can bring the sump pump into action as well.

I finally came across a great example of a good solution to the problem of what to do with sump pump systems when the power goes out or the pump just up and dies—short of installing an automatic generator system. 

The back-up system is water-supply driven.  How this works is that there is a secondary pump that is powered by the house water supply.  While this uses a lot of city water to drive the pump, it will keep your basement from becoming a swimming pool until the power comes back on.  This all assumes an adequate supply of water.

The system just sits there doing nothing as long as the electric sump pump is functioning.  The float that activates the back-up system is set higher in the sump than the float for the primary sump pump.  Water reaching the higher float would be interpreted as failure of the primary pump by the back-up system.

water powered sump pump

The picture shows what the apparatus looks like.  One can see where the water supply goes through the back-flow prevention device and down to the back-up pump.  The back-flow device is required to prevent water in the sump from being sucked back into the house and/or city water supply under negative pressure. 

Relative to the cost of damage that can be caused by failed sump pumps, the cost of these systems is quite reasonable.  You can expect to pay around $150.00 for the water powered sump pump, $100.00 for the back-flow valve, plus the labor and other materials necessary to complete the job.


Charles Buell, Real Estate Inspections in Seattle

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Comment balloon 53 commentsCharles Buell • February 24 2014 05:30AM


Hi Charles,

Not many of these sump pumps around here in this area. But back in Michigan there were a lot of them. They always seem to be going bad because they work so hard in the rainy seasons.

Have a good day in Seattle.

Best, Clint McKie

Posted by Clint Mckie, Desert Sun Home, Comm. Inspection 1-575-706-5586 (Desert Sun Home, commercial Inspections) over 6 years ago

Good morning Charles. This is an important post and I never knew about this solution. I have three pumps so I think I will check it out with my plumber. Suggested. 

Posted by Sheila Anderson, The Real Estate Whisperer Who Listens 732-715-1133 (Referral Group Incorporated) over 6 years ago

Here we go with the city water supply stuff again!

Why is that discharge tubing insulated?

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

Clint, I would imagine that in your area, even if you needed one, water shortages might be a factor as well.

Sheila, check it out---seems to be a good option

Jay, to answer your question, rumor had it that shortly after installation, Billy Jay showed up and put the insulation on there   Question for you.  Don't you see these back flow valves all over the place in your area?  Boilers, lawn sprinklers, fire suppression systems, etc.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

Boilers of course, if they are newer.  The older ones usually not unless they had been recently serviced and the people believed the plumber who suggested one go on there.  Lawn sprinklers never.  Fire suppression systems here are in multi-unit dwellings and the master control is in a closet somewhere in the building, into which I never go.  Not sure I would know what to look for.

On sump pumps, I have never seen one like this.  I have never seen the house water-system pump, so I have never seen such a check valve.

But I do enjoy the pesticide-flavored water.  It's best with purple Kool Aid.

In Ecuador the water was brown and we put a purple Kool Aid powder in it to change the color!  No sugar, just the coloring.  For all I know that powder was worse than pesticides!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

Charles - Good post. Not a lot of need for sump pumps in our area but I'm sure they come in handy back east!

Posted by Jeff Stevens, Jeff Stevens, Associate Broker (Berkshire Hathaway HomeServices New Mexico Properties) over 6 years ago

Charles:  Great .. and very useful .. article.  One that I'll be considering for my own home and passing on to other homeowners that surround me.  Yep, you guessed it.  There are water issues at times.  I've been looking for a back-up solution .. besides the battery-operated sump I have now.  Something more long term and longer-lasting.  This may be it!  Thank you ...


Posted by Gene Mundt, IL/WI Mortgage Originator - FHA/VA/Conv/Jumbo/Portfolio/Refi, 708.921.6331 - 40+ yrs experience (NMLS #216987, IL Lic. 031.0006220, WI Licensed. APMC NMLS #175656) over 6 years ago

Yes, of course they fail when they are needed the most. The good news is that if there is power outage, most insurance policies will cover the damage if sump pump couldn't work. - Debbie

Posted by Women of Westchester Working Together, Women helping Women get ahead (Women of Westchester Working Together) over 6 years ago

Hi Charles - That's a brilliant solution. It does seem that the weather conditions that would create the need could also be responsible for the failure, along with the usual gremlins.

Posted by Dick Greenberg, Northern Colorado Residential Real Estate (New Paradigm Partners LLC) over 6 years ago

This is a big concern with some properties. Dang if the sump pump goes out while residents on vacation. Next door neighbors in Chicagoland were on a one month vacation to Arizona. Their sump pump crashed while they were away. They came back to an entire basement/family room filled with a foot of water, mushrooms growing inside, destroyed wood-paneled walls, and $$$$$ loss in water and mold damage. Even 1st and 2nd floors needed to be gutted. Disaster.

Posted by Jane Chaulklin-Schott, TeamConnect Luxury Homes - Orlando, Florida, 32836 (TEAMCONNECT REALTY - (407) 394-9766) over 6 years ago

Excellent info!  We do property management in the greater Seattle area.  I have sent your article to our maintenance coordinator.

Posted by Brandon Vukelich, Exceptional Service. Stellar Results. (BV Real Estate) over 6 years ago

They are starting to use these around here and since I have city water and an active pump each spring this would be good insurance.

Posted by Brian Clinger, Brian Clinger ABR, GRI, CRS, SRES (Coldwell Banker AJS Schmidt) over 6 years ago

Wow - This is great information. There are many here in Colorado that have back-up secondary pumps should pump 1 fail.  But without power, they won't do you any good.

Posted by Charlie Dresen, Steamboat Springs, CO e-Pro (Steamboat Sotheby's International Realty) over 6 years ago

This post was very informative.  I had no idea there was something like this available.  It certainly seems like something worth investing in.

Posted by Joan Whitebook, Consumer Focused Real Estate Services (BHG The Masiello Group) over 6 years ago

Very important information, Charles!  I recall one home with a basement, that experienced a sump pump failure.  It took out the heating system, and the water heater.  The homeowners were away at grandma's house over Christmas holidays.

Posted by Myrl Jeffcoat, Greater Sacramento Real Estate Agent (GreatWest Realty) over 6 years ago

Great post! I always learn so much from home inspectors.  I really need to have someone out to take a look at one of our pumps.  I think it is out.  If the other one fails we are in trouble...

Posted by Evelyn Johnston, The People You Know, Like and Trust! (Friends & Neighbors Real Estate) over 6 years ago

Charles. that's a great solution to avoid flooding in case there is a power failure. I used to recommend battery back up - however, even battery back up has a short life so this one seems to be a complete solution.

Posted by Praful Thakkar, Andover, MA: Andover Luxury Homes For Sale (LAER Realty Partners) over 6 years ago

Jay, there are tons of these devices around here for sure.  Lots of residential homes with fire-suppression systems that have them too

Jeffrey, I am sure they do

Gene, seems like a great solution to me---not very often that the city supply goes down

Debbie, true, but I would rather avoid the mess of a flood

Dick, there are always gremlins it seems :)

Jane, a lot of water in the basement can do a lot of damage to the entire home---not just the flooded areas

Brandon, that means I will be seeing even more of them! Welcome to AR by the way---we are both in the same neck of the woods :)

Brian, pretty cheap insurance I should think

Charlie, nope---dead batteries and no electricity amounts to just about the same thing

Joan, I have had heard about them and even seen handheld ones that didn't work worth a darn--but this seems like the genuine article

Myrl, yes, one flood of a furnace or a water heater typically means replacement of the units

Evelyn, don't neglect it :)

Praful, when it was an only alternative I thought the batteries might be a good choice---but maintaining charged batteries is no easy task

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

I've installed a few of these, and they work great.  Just need to get one installed at my house now :)

Posted by Joshua Frederick, Home Inspector in Defiance & all of Northwest Ohio (Home Inspector for ASPEC Residential Services, LLC) over 6 years ago


I've seen plenty of battery backups in my area, but never a water backup. Interesting and simple.


Posted by Richard Iarossi, Crofton MD Real Estate, Annapolis MD Real Estate (Coldwell Banker Residential Brokerage) over 6 years ago

The oil company calls and lets you know down in Florida good and bad news about your home in Maine. It is not taking more oil when the delivery truck beep beeps. Backs in to hook up the hose. The warm weather for two days causes melting, and with frost in the Earth the ground water and lots of rain that happens. Well, no place to go but in the cellar... filling up. And the subpump is plugged in for when this happens in spring. But then winter lower temperatures return, the hose out on the lawn freezes up and no more discharge as rain returns and a couple missing down spouts fill up the cellar to the rim to not win. Furnace goes out, under of home freezes plumbing freezes up but the breaks on 2nd floor floor and flow to cause ceilings to come down, rugs to crackers in milk soak up and get mushy. Mold happens. Yikes. All because no one thinks of using subpump in winter. Just spring thaw. Right.

Posted by Andrew Mooers | 207.532.6573, Northern Maine Real Estate-Aroostook County Broker (MOOERS REALTY) over 6 years ago

Oh Charles, this is a great solution I never knew about with town water...had 2 sump pumps with marine battery backups at my last house...i had a stream that basically flowed through the old home...Moved to a DRY basement! lol

Posted by Ginny Gorman, Homes for Sale in Southern RI and beyond (RI Real Estate Services ~ 401-529-7849~ RI Waterfront Real Estate) over 6 years ago

Charles, this is a great solution. I really learned something new today. Thanks.

Posted by Michael Setunsky, Your Commercial Real Estate Link to Northern VA over 6 years ago

This subject is a need to know for those that have to pump...thats all I know

Posted by Richie Alan Naggar, agent & author (people first...then business Ran Right Realty ) over 6 years ago

Ive seen several of these lately and even considering one for my own home. Great picture showing how it works. 

Posted by Scott Seaton Jr. Bourbonnais Kankakee IL Home Inspector, The Home Inspector With a Heart! (SLS Home Inspections-Bradley Bourbonnais Kankakee Manteno) over 6 years ago

Great SUMP Pump tips

Posted by Brian Burke, Broker & Advising Expert-Denver Luxury Real Estate (Kenna Real Estate) over 6 years ago

Josh, you know what they say about the cobblers kid's shoes

Richard, pretty cool for sure

Andrew, whoops---quite the scenario :)

Ginny, I finally drained my sump location to daylight---got rid of the sump pump completely P:)

Michael, glad to help

Richie, sump pumps can be a nightmare of ongoing worry

Scott, thanks

Brian, thanks to you as well

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

Excellent backup system and at a very reasonal cost. Back up battery systems work but only until the battery is drained.  Good alternative to a generator and hopefully we never run out of water.

Posted by Margaret Rome Baltimore 410-530-2400, Sell Your Home With Margaret Rome ( HomeRome Realty 410-530-2400) over 6 years ago

Vacations are always the target dates for water failures.

Posted by Jim Miner, Loan Modfication & Short Sale Specialist (Miner Noh & Associates) over 6 years ago

Great example of a simple back up solution. Now if you are on a well....

Posted by Donald Hester, NCW Home Inspections, LLC (NCW Home Inspections, LLC) over 6 years ago

That sounds like a great solution unless you are on a well that stops pumping when the power goes out.

Posted by Carolyn Roland-Historic Homes For Sale In Delaware and S. Chester County PA, Carolyn Roland, GRI, CRS (Patterson-Schwartz Real Estate) over 6 years ago

Dear Charles,

You taught me something again. I showed a house with 2 feet of water in the basement over the weekend. I bet, they wished, they had spent the money for this system.

Posted by Dörte Engel, ABC - Annapolis, Bowie, Crofton & rest of Maryland (RE/MAX Leading Edge) over 6 years ago

So - about $250 to prevent thousands of dollars in damage. Sounds like a wise investment to me!

Posted by Marte Cliff, Your real estate writer (Marte Cliff Copywriting) over 6 years ago

Thanks for the great information.


Posted by Tina Parker, CNE, REDM, SRES, CSP Home Staging REALTOR, Halifax (Keller Williams Select Realty) over 6 years ago

Sump pump failing to operate due to electricity being shut off is a common cause of drywall and insulation damage in basements of foreclosed homes here in Michigan, and can cause dreaded mold to take over.  Home can become unliveable in a short time.

Posted by Lynn Afton, REALTOR® Near Big Rapids, MI, Mecosta County (Greenridge Realty Oakmont) over 6 years ago

Margaret, and the batteries do not last very long when they are working hard

Jim, it would seem so :)

Don, yes, those dang wells are problematic this way

Carolyn, too true

Dorte, two feet of water is going to be a headache for someone

Marte, yes---plus labor :)

Tina, you are welcome

Lynn, these pumps can never be allowed to fail--back up ins essential I should think

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

Great tip! Thanks Charles! Keep them coming!

Posted by Gary J. Muccio, Associate Broker, Exceptional Customer Service! (Keller Williams of Central PA) over 6 years ago

Real good tip, I'm going to recommend this one to client's during my inspections although here in Az not a whole lot of sump pump/basement applications, great idea however.

Posted by tray raymond (Scottsdale Desert Inspections Inc) over 6 years ago

Interesting! I really need to share this with some homeowners.

Posted by Barbara Jenkins, Its about THE house (Solid Source Realty) over 6 years ago

Gary, I will do my best

Tray, if you need a back up---this seems like a good alternative

Barbara, thanks

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

Seems easy and affordable, doesn't it?

Posted by Kimo Jarrett, Pro Lifestyle Solutions (WikiWiki Realty) over 6 years ago

Charles, this is a great tip that can save a lot of heartache and money.

Posted by Sharon Parisi, Dallas Homes (United Real Estate Dallas ) over 6 years ago
Fabulous idea.. I am sharing with my Portland clients!!
Posted by Dawn Barry-Griffin over 6 years ago

Kimo, does to me.  I am just glad I don't need one :)

Sharon, thanks

Dawn, hope they find it useful

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

Speaking from my own experience, that is great advice, Charles. In the 20 years that we owned our former home, the sump pump failed twice causing all kinds of (expensive) damage. You're right--sump pumps always fail when you need them most.

Our first pump bit the dust within 7 years. Our 2nd one "failed" when the electrical supply was disconnected by a contractor working in our home who did not reconnect it when he left. Our basement was flooded within 24 hours.

Finally, we had a water-powered back-up pump installed for a hundred dollars or so. Hopefully the new owners won't have any more problems!

Posted by Janelle Ancillotti, HSR Certified Home Stager, Syracuse, NY (Seneca Home Staging) over 6 years ago

They never fail when you don't need them!  Sounds like a great tool.  Thanks for the post

Posted by Gene Riemenschneider, Turning Houses into Homes (Home Point Real Estate) over 6 years ago

Janelle, those dang contractors :)

Gene, it only makes sense :)

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

Check with logal city regulations first! I see these installed frequently around here. And they are all illegal as the municipalities can't cope with the wastage of potable water and fire fighting water pressure levels. 

And of course when do citys need that?; Just when the bad weather occurs that's causeing the power outages and flooding in the first place.

Posted by Robert Butler, Montreal Home Inspector | Aspect Inspection (Aspect Inspection) over 6 years ago

Robert, I could see where that could possibly be an issue in areas with water shortages--but that isn't here.  Think of all the extra money the jurisdicion makes by people running up their water bills :)

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

I have seen one of these once. It was quite a few years ago. I do sometimes mention them to my clients, especially in the absence of a generator. 

To answer your question, They are only going to fail when you need them. It is very simple, something sitting idle is not going to fail it can't. I hear that type of comment all the time and it makes me chuckle. We turned on the furnace for the first time and it stopped working just when we needed it.

Well, yeah. No one uses the furnace when it warm 

@ Jay, You don't see back flow preventers on lawn sprinklers? Wow! They are required here and by the UPC. 

Posted by James Quarello, Connecticut Home Inspector (JRV Home Inspection Services, LLC) over 6 years ago

Stuff certainly goes bad when it is not being used and then its condition reveals itself when it is called into action.  They also "fail" to do their job when the power goes out regardless of their condition

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

We're staring to see more of these around here.  The other downside beside high water bills, is significantly lower pump volume.  Even a house with good water flow does not have enough flow to equal a standard sump pump.  It's best to have a battery backup and the water pump as the last resort.

Posted by Rafi Footerman, Home Inspector, Mold Inspector, Radon and More! (Mid Jersey Inspections) over 6 years ago

Interesting device that I never heard of. Thanks for the info.

Posted by Wayne B. Pruner, Tigard Oregon Homes for Sale, Realtor, GRI (Oregon First) almost 6 years ago