If you have a sump pump installed, your basement is protected most of the time. However, mechanical failures in the sump or the sump pump switch can result in a basement water problem. And when rains are at their worst and the waters are rising, you'll be very glad that you have a backup sump pump that can kick in and pick up the slack.
Unlike a battery backup sump pump, a backup sump pump will be able to run as long as there's power in the home, with no worry of the charge running out. In areas with heavy volume (some basements have floodwaters that rise up several feet!), one pump simply is not enough. In this case, you'd need to install a second pump to step up and help with the extra load. A backup sump pump is perfect for this application.
When installing two sump pumps into one location, be sure to use multiple discharge pipes to send the water out of the home. One discharge pipe will not be able to hold the volume of water necessary for two simultaneous pumps, meaning that the second sump is not removing as much water as it should from your home.
Without a battery backup sump pump, the best sump pump system in the world will fail as soon as the power goes out. And unfortunately, the worst rains do not take this into consideration when they knock out your power.
With all the battery backup sump pump options on the market, what can you do? Find out what you can about the benefits of each option.
Generator-powered sump pump backup: About $400 will buy a portable generator that can run the sump pump in the event of a power outage. However, for this generator to be useful to you, you will need to be home- and awake- to turn it on, usually while standing outside in the rain. Alternatively, you can purchase a powerful generator system that is wired to power the sump pump for $7,000-$10,000, with purchase and installation. Will you be able to be home and be awake whenever you lose power? If not, this is not the option for you.
Alternate Sump Pump Power Source: Designed to power sump pumps during outages, alternate sump pump power sources convert a battery's DC power to AC. However, converting DC to AC is a very inefficient process, and much of the charge is lost. These batteries usually run out in about an hour, or with about 2,200 gallons of water pumped out.
Generic Battery Backup Systems: Many contractors will try to rig up a cheap battery backup sump pump to a car battery that sits next to the sump pump. These batteries were not intended for this kind of application, however, and their amperage-hour capacity will drop dramatically after about a year. If there's a flood, they won't help for long.
Sump Pump Battery Backup Systems: Top-quality battery backup sump pumps have been designed especially for crawl space and basement sump systems. Made specifically for this application, these battery backups pump three to five times more water out on one charge than an alternate sump pump power source can. A reliable battery backup sump pump should pump more than 10,000 gallons of water with one charge. If that's not enough, it's usually possible to hook two batteries up to a single backup sump pump as well.
Both. A battery backup sump pump is the most important part of a sump pump system, as it can run when the power goes out and is able to temporarily serve as a battery backup sump pump as well. However, having a full AC powered sump pump as a backup will provide you with a sump pump system that can pump a much higher volume of water out of the basement or crawl space per hour than most battery backups can. Additionally, an AC powered sump pump does not depend on a charge to run, so it can keep going for hours on end without a problem.