You would think Minnesota would be the land of frozen septic systems. But the truth is it has only been the last few years that this has become an issue. The reasons we are seeing more frozen systems are:

Design changes

In the old days, systems were deep, placed well below the frost line. This kept freezing to a minimum (those that did freeze were cases of a plumbing leak flooding the entire area, broken pipes, etc). Today, systems are designed closer to the surface because a shallow system provides better treatment. But even shallow systems don’t freeze (under normal conditions) because the bacterial activity in the effluent keeps the temperatures high enough to prevent freezing.

Installation errors

Even with the higher system temps, the cold will find any flaws in the system. Pipes that have bellies will not drain completely, and any standing water will eventually freeze, causing an ice dam. Also, pump tanks are empty most of the time and do not have the higher levels of bacterial activity. This means the temperatures will drop dramatically, allowing the weep hole to freeze shut. But the effluent line running to the soil area stays full, and with direct contact to the frozen ground, it doesn’t take long to freeze.

Improper use

Many of today’s septic system owners are city transplants. They think nothing of spending a Saturday doing 12 loads of laundry, back-to-back showers, using harsh cleaning compounds (that kill off the good bacteria) and topping it all off with a hot tub party that drains into the septic because they don’t know any better. Homeowners also have high-efficiency furnaces that trickle-dose the system (acid kills bacteria) and water softeners. You also have people who drive snowmobiles over the system, forcing frost deep into the ground. And then you have those who head south for several weeks and the system goes dormant from lack of use.

Changing weather patterns

You cannot argue with the fact that the climate is changing. In Minnesota, winter used to be predictable; by December, we would have up to 12 inches of snow cover, which would insulate the septic systems from the January/February deep freeze. Not any more. Today we can see temperatures in the 40s and 50s around Christmas, which means no snow cover … but then in January it starts dropping to below zero, and with no snow cover, systems freeze quickly.

But it’s not just Minnesota experiencing these weather aberrations. Consider what is happening in the lower states: Texas and Oklahoma are snowed-in and California lost a citrus crop due to freezing. With weather like this, frozen septic systems will be more than just a Northern problem.

Of course, some will think you can make a lot of money thawing those systems out … and you can, but it’s not quite the ideal opportunity you would think. Just ask contractors what life was like in the Midwest in 2003. At first they loved it, but soon they found themselves working 18 to 20 hours a day, 7 days a week in below-zero conditions. That gets old quick.

The contractors soon grew tired of customers complaining. And something else … I was fielding calls for months from people who wanted to sue their septic contractors. And it didn’t matter what I said; they were convinced the contractor installed systems that would freeze to “guarantee future work” and said, “I can’t wait until they run the city sewer out here.”

Design challenges

When a system freezes, it doesn’t do your reputation any favors. But there are a few simple (and inexpensive) tips you can follow to minimize problems. First, make sure all pipes have adequate drop and no bellies. Secondly, sleeve the pipes. If you have a 2-inch pipe, put it inside a 4-inch pipe. This way the water-carrying pipe never comes in direct contact with the frozen ground.

If the system has a pump chamber, use soil-approved insulation to insulate the top and upper half of the tank. Do the same for inspection pipes and risers. If customers have a water softener/high-efficiency furnace, you can install a separate, legal drywell to take the discharge from these appliances.

And you should also make sure customers know the rules about using the system properly, including maintaining a good insulating snow layer by not driving snowmobiles and ATVs over the system.

The best plan is to design systems with freezing in mind, fix problems when a system freezes and offer your customer solutions to prevent freezing in the future. Take care of your customers and they will take care of you.