A level float full of last year’s leaves
An unmanned irrigation tank on a windbreak kept texting a high-level warning to a number that nobody had checked since harvest. When someone finally walked the berm, the sight glass showed a comfortable mid-tank. The float switch did not.
Oak leaves had packed the stilling well. The float was pinned up as if the tank were full. The sensor was honest about its own jammed position and dishonest about the water.
Clearing the well took twenty minutes. Adding a coarse screen the operator already had in a shed took another ten. The high-level alerts stopped. We still wrote the episode into the seasonal outdoor check list, because the same well will pack again next autumn if nobody owns the walk.
Telemetry does not replace a pair of gloves. If a remote tank’s story disagrees with a sight glass, climb the ladder before you order a new probe.