My Zoeller was installed in 1969 and I am still not worried about it...

There is no average life span for a sump pump, just like there is no average life span for an automobile. Just like a car, it depends on how they are used. Some sump pumps run almost constantly, some never.

If you are worried about it failing, install a battery back up sump pump. There are some very good ones available. We install units made by Glentronics. They are a little more expensive than some but are very well made and have some great features. They also have a great combo unit that has the main pump and back up mounted on the same plate, pre-plumbed with check valves. Puchase their deep cycle battery if you can. It comes with a separate acid pack, so it hasn't been sitting on a shelf somewhere. It also has a probe for keeping track of the battery condition which is connected to the control box. The control box also has alarms for any possible failure of the sump pump system. They are expensive, but they are not cheap. They are worth the money, especially if you have a finished basement and it saves you from an expensive homeowners insurance claim. Glentronics website is www.stopflooding.com.

Do not use a water powered back up sump pump. Their performance is inferior and they require a backflow preventer to be installed because they create a cross-connection between the sump pump water and the domestic water supply. The backflow preventer will have to be tested annually by a certified tester.

Remember, it's better to have and not need than need and not have.

Good Luck

Here is a link that might be useful: Lemay Plumbing, Inc., a St. Louis Plumbing Contractor

In all fairness, even though my Zoeller was initially installed in 1969 it sees very light use and it is only pushing into a 6ft static head.

Mine is a pedastal pump with an open frame electric motor that has oil ports on the motor bearings. About twice a year I pull the pump, clean the pump intake screen and oil the motor bearings. Then I unplug the pump and fill the sump with water. Once the sump is full I start the pump and use a snap-on amp meter to measure the full load amps of the motor. The amperage measures within 10% of the manufacturers rating which tells me the pump is working correctly and the motor bearings are okay.

I did have to change the pump impellar once, but that was because a piece of gravel got into the pump and tore up the original impeller.

Use a pedestal pump with a larger HP than needed motor and a high service rating (over 1.00).