A backup sump pump takes over when your main pump fails or the power goes out. In high water table areas that's not a rare event, so a backup is one of the best investments you can make in your basement. There are two main types.
Battery backup pumps
A second pump sits in the basin, wired to a deep-cycle battery and a charger. If the main pump can't keep up or loses power, the backup switches on.
- Pros: works with any water supply, including private wells; many models alarm when they run.
- Cons: runs only as long as the battery lasts, which may not be long in a heavy, all-day spring outage; the battery needs replacing every few years.
Water-powered backup pumps
These use your home's city water pressure to pull water out of the basin, with no electricity needed.
- Pros: no battery to wear out; can run as long as water pressure holds.
- Cons: needs municipal water with good pressure, so they're generally not suited to homes on private wells; they use water while running; may need a backflow device to meet plumbing code.
Which is better?
If you're on city water and your pump runs heavily for long stretches, a water-powered backup can be a strong choice. If you're on a well, as many homes in East Bethel or Ham Lake are, a battery backup is usually the option. Some homeowners add a generator plan as well.
Don't forget maintenance
Test any backup every spring. For battery units, check the battery's age and the charger light. For water-powered units, make sure the supply valve is open.