When designing or installing a sewer lift station, one often-overlooked factor is the freeze line—the depth at which the ground freezes during cold weather. While it might not seem like a big deal, the freeze line can vary significantly from place to place, and it plays an important role in protecting your system from costly damage.
What Is the Freeze Line?
The freeze line (or frost depth) is the maximum depth at which soil water will freeze during the coldest part of the year. In warmer climates, it may be just a few inches below the surface, while in colder northern regions, it can be several feet deep. Local building codes often specify this depth to ensure pipes, wiring, and other infrastructure are installed deep enough to avoid freezing.
Why It Matters for Sewer Lift Stations
If a sewer lift station’s components—such as piping, valves, or electrical conduits—are placed above the freeze line, cold weather can cause:
- Frozen Pipes – This can completely block flow and cause backups.
- Damaged Components – Ice expansion can crack pipes, fittings, or valves.
- System Downtime – Repairs during freezing conditions are costly and inconvenient.
The risk isn’t just for areas that regularly see snow. Even regions with occasional hard freezes can experience damage if components aren’t buried deep enough.
How Freeze Line Depth Varies
- Northern States – Freeze lines can reach 3–6 feet or more.
- Mid-South Regions – Depths often range from 1–3 feet.
- Southern States – The freeze line may be less than a foot, but severe cold snaps can still cause issues.
This variation means a design that works in one location might fail in another if freeze protection isn’t considered.
Protecting Your Lift Station from Freezing
- Follow Local Code Requirements – These are based on historical freeze line data for your area.
- Insulate Above-Ground Components – Valves, hatches, and exposed piping can be wrapped or heat-traced.
- Bury Piping Below the Freeze Line – Ensures continuous flow even in extreme weather.
- Plan for Worst-Case Weather – Occasional cold snaps can be just as damaging as consistent freezing.
At Triple D Pump Company, we design and install sewer lift stations with local freeze line depths in mind, ensuring your system stays operational no matter the weather. Our team can help you determine the correct depth and freeze protection for your specific location.
Fill out the form below for a free quote, or give us a call. We will be happy to answer any questions you have, and work with you to design the perfect custom lift station for your next project. With decades of experience we know about all of the fine details to build your wastewater lift station for durability and efficiency.
