What to notice
Build a pattern grid
Record one fixture, one room, one floor, or whole-house involvement. Include whether flow drops only when another outlet runs. A clogged aerator, valve, branch condition, hot-water component, pressure regulator, service line, or public supply issue can look similar from one tap. The grid does not choose among them but makes the call clearer.
Time and recent changes matter
Note whether the change was sudden or gradual and whether plumbing work, utility activity, freezing weather, or a new appliance preceded it. Ask household members what they observed rather than repeatedly opening every fixture. A district notice is important context, but it may not explain a problem isolated to one faucet.
Ask for measurement and boundaries
If a provider proposes pressure testing, ask where it will be measured and how static and flowing conditions are interpreted. A pressure number alone may not identify a restriction. Confirm whether the scope includes fixture service, a private service line, a control device, or coordination with DWWD.