How Much Does Main Water Line Repair Cost in St. Louis? [2025 Data]

A main water line repair in St. Louis costs an average of $909. Most homeowners pay between $732 and $1,350, depending on factors like the size of the repair and the extent and cause of the damage. If your home, like many others in St. Louis, has a basement with a water meter located inside, your total could be much lower, as you won’t need expensive excavation. However, the water infrastructure in St. Louis is nearing 100 years old, so you could pay closer to $1,800 for a replacement if your water main is corroded from old age.

Main Water Line Repair Cost Factors

The cost to repair a main water line in St. Louis can sit as low as $578 or climb up to $1,500. Your total will depend on a few factors, including the size of the damaged area, the extent of the problem, and ease of accessibility.

Size

You can expect to pay between $100 and $200 per linear foot for your water main repair, which means your costs will go up as the damaged section of the pipe gets longer. You’ll pay below-average prices if you have a small crack that doesn’t span along the length of the line. On the other hand, widespread damage from corrosion—which is common in St. Louis due to the aging water infrastructure—can easily push your costs closer to the $1,500 mark.

The good news is that the average lot size in St. Louis is just 0.098 acres, which is well below the national average. If you have an underground supply line that’s damaged and requires excavation to reach, the short stretch of the pipe from the street to your home generally means more affordable repairs.

Type and Extent of the Damage

The type and extent of the damage to your main water line are two other major factors to consider. In St. Louis, two common issues that damage water mains are expansion and contraction of the soil. This can happen with changes in moisture or movement from freeze-thaw cycles through hot summers and cold winters. These underlying problems can lead to smaller cracks, the repairs for which are relatively affordable.

On the other end of the spectrum, you have corrosion. The average home age in St. Louis was built in the mid-1960s and is approaching 60 years of age. Galvanized steel was the common material for lateral water lines up until the ‘90s, when builders realized the material would corrode within 40 to 60 years. As a result, many of the water mains in St. Louis are reaching the end of their expected lifespan. Replacing a corroded section of pipe isn’t always possible, so a full replacement may be necessary. Water main replacement costs closer to $1,500 in St. Louis.

Materials

Modern water mains running to residential homes are usually made from ductile iron. The cost for replacement sections is moderate compared to other options, like PVC and copper. PVC is the most affordable material but has the shortest lifespan, while copper is the most expensive and lasts the longest. You can ask a plumber about water main replacement materials to find what’s best for your home and budget.

The table below includes material costs for the three common options. Just keep in mind that these include the materials only, and labor costs also vary by material, with PVC being the easiest to work with and coming with the lowest related labor costs, followed by copper and then ductile iron.

Accessibility

Finally, how accessible your water main is can drastically affect your total costs.

You can expect to pay much less than the average if you have a basement that houses your water main. You’re only responsible for the piping on the “house side” of your water main, so any damaged sections of your water main would be easily accessible.

Homes that have water meters buried underground—and those that don’t have water meters—have water mains that are also buried. If that’s the case on your property, you’ll pay far higher prices for excavation to access the line, which drives up labor costs. Luckily, the frost line in St. Louis averages just 15 inches, so water mains aren’t under multiple feet of soil that require excessive excavation. This is a big reason why water main repair in St. Louis costs just 70% of the national average.

However, your costs could go up by hundreds or even thousands of dollars if your plumber needs to break up concrete walkways, driveways, or other landscaping features to access the damaged section of piping.

Plumber Costs

The average labor cost for a plumber in St. Louis to repair your water main is $660. That means that up to 90% of the cost of main water line repairs goes toward labor. 

That includes the average cost of excavation and the actual repair. It doesn’t include the cost of an inspection to find the leak, but the City of St. Louis will conduct its own inspection when you report an issue.

You’ll also need to pay for the appropriate permit for the work. The City of St. Louis charges a flat rate of $94 for the two inspections required, plus $0.20 per linear foot of water main your plumber is repairing or replacing.

Does Water Main Repairs Increase Home Value?

Repairing a water main won’t increase your home value, but it will prevent it from decreasing as a result of water damage and other related issues. However, hiring a plumber in St. Louis to fully replace your main water line will increase your home value, as buyers will know that they likely have decades before they need to worry about another issue. That peace of mind could lead buyers to pay more, especially in a city with such an old water delivery system.

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We extensively research project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We rely on reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects. 

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