Use a water powered sump pump as a backup system because it will work indefinitely even in a blackout. Let’s look at the best one and the features that matter.

Best Water Powered Sump Pump PicWhen does water fill your sump pit fastest?

During a storm or when snow is melting, right?

Let me tell you a story to illustrate why a water powered sump pump backup system is ideal for a lot of people:

My sister owns a home with a basement in an area of the US prone to electrical blackouts. In August of last year there was a big storm that passed through bringing large amounts of rain and wind. The wind knocked down the electrical and her basement sump pit started filling fast.

A few weeks earlier they installed a water powered backup pumping system because they wanted to protect their recently renovated basement. And as it so happens, if it wasn’t for doing that, their $15,000 investment would need to be renovated a little bit again – damage would have been done to the carpet, drywall and electrical, and other furniture and electronics.

Think about if you’re out of town and your primary pump fails leaving the work to your battery backup system. The battery backup will last 6-8 hrs if running continuously… This could mean you return from holiday to a badly flooded and damaged basement.

How Does a Water Powered Sump Pump Work 

Think of the PVC pipe in the sump pit as a giant straw. When the float switch activates the pump ejector, city water rushes through the pump sucking the air out of the down-pipe. Now the pressure within the pipe is much lower than in the room and the water from the sump pit rushes up the pipe – pushed by the higher pressure room air.

With a straw in your lemonade what happens is you suck the air out of the straw creating an almost vacuum. Then the air in the room actually pushes the lemonade up the straw.

What are the flow rates and cost?

If the city water is 90 PSI then every 1 GPM can pull 2 GPM out of the sump pit. And given how much flows through the ejector it can drain your sump at a rate of about 13 GPM. Now that’s a decent amount of water to discharge somewhere but better than having a flooded basement.

The cost of the water to keep the suction is similar to the cost of electricity to run the primary pump – about 3 cents each minute. So if your primary fails the cost of water over a full day of use is about $4 (running for 30 seconds every 5 minutes).

Best Water Powered Backup Sump Pump


1) Basepump RB750 Water Powered Backup

Basepump 750 water powered backup sump pumpWith easy installation and no moving parts to maintain the Basepump water powered backup system is the best choice for most people.

It comes with a 5 year limited warranty. It has a the ability to drain about 13 GPM from your sump pit with 10 ft of lift to the discharge. It has no need for a battery and will operate when your power goes out.

The best part of this water powered backup is it has no maintenance, no need for electricity and unlimited operation time – so you can rest easy leaving your basement alone (for months) with this water powered sump pump.



1. Basepump product page for the RB750.

2. Basepump FAQ page.

3. How do drinking straws work. page by Don Ulin.

4. Wikipedia ‘Suction’ page.