InstallationUpdated July 3, 2026
Plenty of houses around Mount Prospect were built when code requirements and water usage expectations were different. With most homes in the area dating back to the 1950s through the 1970s, we still see a lot of original half-inch or three-quarter-inch supply lines coming in from the curb. These old pipes might have been good enough for a single bathroom and limited fixtures, but they struggle to keep up with modern demands. If your showers go cold when someone runs a faucet, or if you're constantly dealing with low water pressure, an undersized water service could be the culprit.
Why Older Mount Prospect Homes Struggle With Water Pressure
Many older homes in this region have original galvanized, copper, or even lead water lines that have served for decades. Galvanized steel pipes are especially common in the northwest Chicago suburbs and are notorious for corrosion and interior buildup. As sediment from moderately hard Lake Michigan water accumulates, it narrows the inside diameter of already small pipes. Couple that with more bathrooms and appliances than these homes were built for, and you end up with pressure drops all over the house.
Another factor here is code changes. The minimum size for a main water service line has increased over the years. What passed inspection in 1965 might not meet the standard today if you remodel or add fixtures. If you're thinking about upgrading your kitchen or adding a bathroom, it's important to consider the capacity of your existing water main. Learn more about repiping options if your home still has old supply lines.
Signs Your Water Service Needs an Upgrade
You don't need to be a plumber to notice the symptoms of an undersized or deteriorated water line. Some of the most common warning signs include:
- Frequent drops in pressure when multiple fixtures run at once
- Slow or weak flow at hose bibs or outside spigots
- Fluctuating water temperature during showers
- Visible corrosion or leaks at exposed supply pipes
- Evidence of rust or minerals in faucet aerators
- Unexplained wet spots in the yard above the main line
If you're experiencing any of these, it might be time to take a closer look at your incoming water line. Our crew uses tried-and-true methods, from pressure testing to leak detection, to pinpoint the source of the problem before we recommend a solution.
The Process of Upgrading Your Water Line
Replacing an old, undersized water line isn't as simple as swapping out a pipe under the sink. In Mount Prospect, water service runs underground from the street shutoff (sometimes called a buffalo box or B-box) right into your basement or crawlspace. Heavy clay soils, a high water table, and frequent freeze-thaw cycles each winter make excavation more challenging in this area.
Our process usually starts with a site evaluation, measuring your current line size and pressure. We check for code compliance and help you select the right pipe diameter for your needs, usually one inch or larger for updated family homes. The installation itself involves trenching or, where possible, using a pipe-bursting or directional boring method to minimize disruption to your yard. After getting village permits and scheduling inspections, we connect the new line at both ends, pressure-test for leaks, and ensure your system is ready for decades of reliable use.
What to Expect During the Upgrade
Expect some digging, especially in the parkway or yard. Depending on the length and path of the line, the work can take a day or two. We coordinate with the village for permits and inspections, and always take care to protect landscaping and hardscaping where possible. If you have a sump pit, it's worth confirming that your sump pump is in good shape before starting major yard work, because Mount Prospect's high water table means even a short outage during pipe replacement can let groundwater seep in quickly.
Once the new line is in place, you'll notice stronger, more consistent water pressure right away. For homes with older water heaters or rusty galvanized piping inside, this is also a good time to consider other upgrades. Our team can help with water heater replacement and drain updates if needed. We understand how all these systems work together, one weak link can affect everything.
Protecting Your Investment
With a modern, code-compliant water service, you'll get reliable flow for daily living and less worry about hidden corrosion. To get the most out of your upgrade:
- Flush your lines after installation to clear any debris
- Maintain all shutoff valves and test them yearly
- Install a pressure-reducing valve (PRV) if your new line brings in higher pressure than your fixtures are rated for
- Schedule periodic checks for leaks or changes in water flow
If you have older clay-tile or cast iron sewer lines, keep in mind that digging for a new water service can uncover other issues. It's smart to talk to us about your sewer line condition at the same time to avoid repeat yard work.
If you own a home in Mount Prospect and have water pressure woes or outdated supply lines, our experienced team can guide you through a safe, efficient upgrade. Call us at 224-524-1247 to schedule an assessment or get straight answers to your water service questions.