Why Your Water Pressure Keeps Dropping: Common Causes In Denver Metro Homes

If your water pressure has been dropping lately — or it's always been weaker than you'd like — the cause is usually one of a handful of things, and most of them are fixable without tearing into walls. Here's what we check first when a Denver metro homeowner calls about low pressure.

1. Is It One Fixture Or The Whole House?

Start here. If only one faucet or showerhead is weak, the problem is usually local — a clogged aerator, a failing cartridge, or mineral buildup right at that fixture. If pressure is low throughout the entire house, the cause is further upstream: the main line, a shared valve, or the pressure coming in from the street.

2. A Partially Closed Or Failing Shut-Off Valve

The main shut-off valve (or a valve near the water meter) doesn't have to be fully closed to choke your pressure — even a quarter-turn can make a noticeable difference. Older gate valves are especially prone to this as their internal components wear out over time. It's a quick, inexpensive fix to check and replace if needed.

3. Mineral Buildup In Older Pipes

A lot of homes across the Denver metro — especially in the older neighborhoods of Denver, Lakewood, Littleton, and Englewood — still have galvanized steel pipe from decades ago. Over the years, mineral scale builds up on the inside of these pipes and narrows the path water has to travel through, which shows up as gradually worsening pressure rather than a sudden drop.

4. A Failing Pressure Reducing Valve (PRV)

Many homes have a pressure reducing valve where the main line enters the house, especially in areas with naturally high municipal pressure. When a PRV starts to fail, it can either restrict flow too much or let pressure swing unpredictably. If your pressure seems inconsistent rather than just low, this is one of the first things we test.

5. A Hidden Leak Robbing Your Pressure

A leak anywhere in your line — under a slab, behind a wall, or underground between the meter and the house — splits your water supply between the leak and your fixtures. If your pressure has dropped at the same time as a higher-than-usual water bill, or you've noticed damp spots, warm patches on the floor, or the sound of running water when nothing's on, a leak is worth ruling out with a proper inspection before anything else.

6. Municipal Supply Changes

Less common, but worth mentioning: sometimes the pressure coming from the street itself changes due to utility work, high demand in your area, or elevation changes in hillier parts of the metro like Evergreen or parts of Golden and Lakewood. If your neighbors are seeing the same drop around the same time, it's worth a call to your water utility before assuming it's something inside your home.