What Causes a Water Main Break?

If you suspect a water main break on your property, it’s important to act fast. But what causes a water main break? Disaster can strike and break your water main in many different ways, but some causes are much more common than others. Learn what hazards to watch out for, what happens when a water main breaks, and who you can call to fix yours. 

What Happens When a Water Main Breaks?

A water main is a large pipe that delivers potable water from the water supply source to homes, businesses, and other nearby buildings. When a water main breaks, it means the pipe ruptured or cracked, leading to a disruption in water service, potential flooding, and the risk of water contamination. Water main breaks often require urgent repairs to restore a very necessary service to the surrounding area, while preventing further damage. 

Common Causes of Water Main Breaks

Many different potential issues can lead to a water main breaking, so let’s look at some common ones to watch out for. 

Aging Infrastructure

As water mains age, the materials they’re made from can weaken, leading to cracks or breaks. Older pipes, especially those made from cast iron or steel, are more prone to failure, as the materials corrode over time. This corrosion weakens the structural integrity and makes the pipes more susceptible to bursting.

Extreme Weather Conditions

Severe weather events (such as freezing temperatures) can cause water mains to break. When water in pipes freezes, it expands and places pressure on the pipe walls. As the ice thaws, the pipe can crack or rupture. On the flip side, extreme heat or rapid temperature changes can stress the materials, contributing to breakages.

High Water Pressure

Excessive water pressure can strain pipes, causing them to crack or burst. If the water pressure exceeds the pipe’s capacity, it can lead to ruptures, especially in older or weakened pipes. Consistent high pressure can also result in the gradual degradation of the pipe material.

Ground Shifting or Settling

Natural shifts in the ground, such as soil erosion, settling, or earthquakes, can displace or damage water mains. Even minor changes in the soil’s composition can place undue stress on pipes, potentially causing fractures or breaks.

Construction or Excavation Damage

Heavy machinery used for construction or excavation near water mains can accidentally damage pipes. If a pipe is struck or disturbed by equipment like backhoes, it can crack or rupture. Ultimately, this can cause a break to occur.

Corrosion and Rust

Corrosion due to rust, particularly in older metal pipes, can cause small cracks to form over time. These cracks eventually grow larger, leading to leaks or complete breaks in the water main. Corrosion is more common in areas with acidic soil or where pipes are exposed to moisture over extended periods.

Who to Hire to Fix a Water Main Break

To fix a water main break, you should hire a licensed plumbing professional near you with experience in repairing water mains. It's essential to choose someone who is familiar with local regulations and the specific requirements of water main repairs.

Hiring a local expert ensures timely service and that the repair meets all safety and legal standards. The cost of this project varies based on factors like where you live, the cause of the break, and who you hire. On average, the cost to repair a main water line is around $1,025, but it can range from $350 to $1,700.