That valve under the sink has not moved in years
You reach under the kitchen sink or behind the toilet to shut off the water, maybe because a supply line is dripping or you are swapping out a faucet, and the valve will not budge. It turns a quarter inch and stops, or it spins loose without actually closing anything, or the handle feels fused in place. This is one of the most common surprises homeowners in Springfield run into, usually at the worst possible moment, with water already running somewhere it should not be.
Shutoff valves are meant to be used occasionally, not constantly, but they are also not meant to sit completely untouched for ten or fifteen years. That is exactly what happens in most houses. Nobody touches the valve under the bathroom sink until the day they need it, and by then mineral deposits and corrosion have locked the internal mechanism in place.
Why this is especially common in older Springfield homes
A lot of the housing stock around Springfield, Republic, Nixa, and the surrounding area dates back to the 1950s through the 1980s, with plenty of older homes in the central city neighborhoods going back further. Many of these houses still have their original shutoff valves, especially the gate valves that were standard before quarter-turn ball valves became common. Gate valves are more prone to seizing because they rely on a threaded stem that corrodes over time, particularly with the mineral content in our local water supply.
Ozark region water tends to run on the harder side, which means mineral buildup inside valves and fixtures happens faster than it would in places with softer water. Combine that with decades of a valve never being touched, and you get a shutoff that looks fine from the outside but is effectively dead inside.
More on this from The Shutoff Valves That Seize Because Nobody Turns Them.
What the seasons do to these valves
Springfield's weather swings hard between a humid, sticky summer and winters that can drop well below freezing with little warning. Houses here deal with real thermal expansion and contraction every year, and that movement affects plumbing lines and the valves attached to them. A valve that seemed fine in October can crack or seize after a hard freeze in January, especially if it sits in an unheated crawlspace, garage, or exterior wall, which is common in this area because of how many homes were built with crawlspace foundations rather than full basements.
Freeze and thaw cycles also stress the washers and seals inside older valves. Even if the valve handle turns, the internal seal may no longer hold, so you get a slow drip or a handle that moves but does not actually stop the water. This is worth checking before winter sets in, not during a cold snap when you actually need the valve to work.
What you can check yourself
Twice a year, maybe once before winter and once in late spring, go around the house and gently test every shutoff valve you can find: under sinks, behind toilets, at the water heater, and the main shutoff where the line enters the house. Turn each one a quarter turn and back, just enough to confirm it moves freely, then return it to its original position. You are not trying to shut off water for real, just confirming the mechanism still works.
If a valve feels stiff, do not force it. A corroded valve can snap off in your hand, and a gate valve under enough pressure can crack at the stem, turning a stuck valve into an active leak. A little penetrating oil on the stem and a gentle, patient turn is reasonable. Forcing it with pliers or a wrench is how a small annoyance becomes a flooded cabinet.
When it stops being a homeowner job
If a valve will not move at all, or moves but does not stop water flow, it needs to be replaced rather than coaxed along. This usually means cutting into the supply line, which is a bigger job than it looks like from the outside, especially on older galvanized or copper lines where fittings have corroded together. Trying to force a replacement on your own can turn one bad valve into a burst pipe behind a wall.
It is also worth having the main shutoff valve for the house checked if you have never tested it or do not know where it is. That is the one valve you genuinely cannot afford to have fail, because it is your only way to stop water to the entire house in an emergency. If you discover during a leak that the main shutoff will not turn, that is the moment to call an emergency plumber in Springfield MO rather than keep working at it, because every minute spent fighting a frozen valve is a minute water keeps running somewhere in the house.