One fixture or the whole house?
Start by checking every faucet. Low pressure at a single fixture is almost always a clogged aerator, cartridge or shower head. Low pressure everywhere points to the main line, the pressure regulator, a partially closed shut-off valve or a leak.
Common whole-house causes
A failing pressure-reducing valve (common after 10–15 years), a main water line leak, heavy mineral scaling inside old galvanized pipes, or a municipal supply issue. A plumber can test static and flow pressure in minutes to narrow it down.
Galvanized pipe and repiping
Homes built before the 1970s often have galvanized steel supply lines that corrode from the inside. Flow slows year after year until the only real fix is repiping with PEX or copper — which also solves rusty water and repeated leaks.
Get it diagnosed
If you've checked aerators and valves and pressure is still low, schedule a pressure test and leak check. It's a quick visit that can prevent a much more expensive problem.
Need a plumber for this?
MGA Plumbing provides water line repair 24/7 in every Missouri city — Kansas City, St. Louis, Springfield, Columbia and hundreds more. Upfront pricing, same-day service. Call (888) 480-9811.