Why Do I Need an Exterior Sump Pump and How Does It Work?

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You probably know what a basement sump pump is and what it does but what is an exterior sump pump? Why might I need one? How does an outdoor sump pump work differently? Well, lets dive in.

Why Do I Need an Exterior Sump Pump In The Yard?

In a word: flooding. Prevention of flooding the yard, garden, garage, house and the neighbor’s property.

Being sued by the neighbor because your basement sump pump dumped water into his house will be very expensive.

  • Does a puddle form in the yard after a rainstorm?
  • Is there a puddle in the yard because the basement sump pump is pumping water into the yard?

Either of these situations could flow that water into the neighbor’s property. However, before the water gets to the neighbor’s house it might flow back into your basement.

That means that your basement sump pump is pumping the same water over and over again. That is why the pump runs constantly and why the electric bill is draining the bank account.

he Zoeller 105-0001 sump pump kit shown below can be used indoors for basement wet bars, showers, or clothes washers. However, by drilling holes in the sump basin it could be used outdoors. It juses the very popular Zoeller M53 sump pump.

Zoeller 105-0001 Sump Pump, 12.50 x 14.50 x 14.50 inches, 19 Pound
  • Automatic, float operated mechanical switch 115V/1 Ph
  • 1-1/2″ NPT discharge
  • 9 ft. UL listed 3-wire cord and plug
  • 1550 RPM, 60 Hz on 50 series models
  • Non-clogging vortex impeller

The solution is to get the water out of the basement and out of the yard. To do that you may need:

  • An exterior sump pump and a buried drain pipe.
  • A French drain and a dry well.
  • A French drain and an exterior sump pump.
  • Or an outdoor sump basin and sump pump with a drain hose.

Typical Uses For An Exterior Sump Pump

Where I live, we have lots of hills. Which means that many driveways, yards, and roof gutter down spouts push water against the house foundation. Or right up to the garage door and flooding the garage.

Many areas have a high water table. When it rains the water table rises and forces water into basements. Which is one reason for having a basement sump pump.

Even if your basement stays dry, you may have a low spot in the yard that collects water. That makes the yard unusable and breeds mosquitos. Also, the low spot might overflow and push water towards the house or garage.

The solution is to put an outdoor sump pit basin where the problem is and pump the water through a burried pipe to where the water can drain harmlessly.

Is An Outdoor Sump Pump The Same As A Basement Sump Pump?

Generally speaking, the answer is “yes”. However, an exterior sump pump used outdoors is usually a bigger machine. That means more horse power and able to pump more gallons of water per hour.

It is quite possible that an identical basement sump pump could be used outdoors but that depends upon your personal situation.

When Do I need A Dry Well and Exterior Pump?

First you need an outdoor sump pump basin and a sump pump to push the water to the dry well. That is usually done with a burried plastic pipe. Although a French drain could be used instead of the pipe.

The French drain could be used to collect additional water along the route to the dry well. Or potentially the earth between the sump pump and the dry well can be used to absorb some of the water.

The dry well shown below can be linked side by side or stacked vertically for larger water volumes.

NDS FWAS24 50 Gal. Flo Stormwater Dry Well System Kit with 3 Side Panels & 1 Cover, Ideal for Rainwater Collection, Black
  • COLLECT, DETAIN, AND INFILTRATE EXCESS WATER: Puts excess water back into the ground; the Flo-Well Dry Well is ideal for residential and commercial locations such as yards, playgrounds, golf courses, wash-down areas, rain gardens and bioswales
  • HOW TO INSTALL: Connect to 4 in. Sewer and Drain (S&D) Pipe through top cover knockout; 12 side-panel knockout points connect to 4 in. S&D and Sch. 40 Pipes; Can be buried or stacked up to 8 ft. deep and supports pedestrian traffic including lawn tractors
  • GRAVEL-FREE ALTERNATIVE: Unlike a traditional dry well that requires filling an large hole with heavy stone and gravel, the Flo-Well Dry Well only needs a small amount of gravel at the base to prevent scouring and provides 250% more detention volume
  • USE ONE OR MANY: The Flo-Well Dry Well works as a stand alone product and can be used in multiples; units can be stacked up to 4 high or side-by-side 18 in. apart
  • INCLUDES: 3 side panels and top cover, unassembled; open bottom allows water to seep into gravel and ground below; bottom panel sold separately to provide a base for a sump pump if desired

The purpose of a dry well is to store water and let it out slowly so the earth can absorb the water. However, if the drywell is too close to the house that water will end up back in the basement. Also, it can’t be located next to the neighbor’s property for the same reason.

Another reason to not use a dry well is because the earth is a thick clay that will not let the water pass through it fast enough to be of any use.

Also, a dry well that is too small for the amount of water pumped to it is nearly useless.

Does the yard have a high water table? That would be another reason to not use a dry well.

So, where do I put a dry well? Preferably in the lowest spot in the yard, that has good drainage, and where the water won’t damage anything.

If you live in the city a dry well is not likely to be practical.

Do I need A French Drain and An Outdoor Sump Pump?

If a French drain can be sloped downwards and extends far enough away to safely release the water then the answer is “no”. However, if the water must move up hill before it can drain into the street or sewer, then the answer is “yes”.

A common usage of a French drain is where it runs along side the house. This is used to prevent surface water from entering the basement and requiring a basement sump pump. In this situation the French drain collects the water and lets it drain far away from the house. This will save a lot electricity.

Unfortunately, many times an exterior sump pump is needed to pump the water from the french drain through a burried pipe. That pipe releases the water into the street, a lake, creek or river, or just a big ditch.

The trench drain shown below is an easy replacement for a French drain and is much less expensive.

No products found.

Can I Use An Outdoor Sump Basin and Pump With A Drain Hose?

This is not ideal but it is a fast solution as compared to digging a French drain or burrying a pipe in the ground.

In an emergency, just set the sump pump in the wet spot and run the hose to where the water can drain safely.

For a more permanent solution dig a hole to place the sump pump basin into. Then connect the hose and run it out to the street or eslewhere. Be sure that the hose will stay where you placed it when the pump starts automatically and you are away.

Some cities will allow the water to be put into the sewer system and others forbid it. This option is becoming less available because it requires building larger waste water treatment facilities.

Crawl Space Sump Pump with Kit
  • Country Of Origin: United States
  • Brand Name: Foeller
  • Can Be Giftwrapped
  • Color: Black

Electricians For Outdoor Installations

We haven’t talked about electricity to run the exterior sump pump. It would be best to hire a licensed electrician to do this job. Water and electricity is a deadly mix.

You could still dig the trench for the electrcian to place the power cables to save some money.

Final Thoughts

The best solution to to a wet yard is a French drain that collects the water and dumps it where it needs to go.

For large property owners a dry well is a great option, with or without a French drain.

For city dwellers the next best solution is an exterior sump pump basin and pump located at the problem spot. It collects the water and pumps it through a pipe to where the water drains away.

Another option is a French drain to collect the water and let the outdoor sump pump push the water as short a distance as possible.

Liberty Pumps CSP-237 Pump, one-size, Gray
70 Reviews
Liberty Pumps CSP-237 Pump, one-size, Gray
  • 16.5″ x 15″ poly sump pit (perforated) and poly cover
  • Automatic sump pump, 115 V, with 10′ power cord
  • 24′ flexible hose kit, polyethylene 1-1/4″ (Model DHK-24)
  • Check valve threads directly into pump discharge

Last update on 2024-05-24 / Affiliate links / Images from Amazon Product Advertising API

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