That may be his official capacity in normal situations, but during an emergency, I’m sure he can operate a truck while others us the associated equipment.
Even manning radios to get other personnel out at the sharp end of the stick, or working at the DPW building keeping track of available equipment can be an appreciable help. In a disaster situation there are a large number of jobs that need warm bodies to fill them, but don’t require much more than that.
Which completely ignores the possibility that the worker in question has other skills besides using a weed sprayer. In some DPWs such cushy jobs are reserved for the guys who’ve stuck through all the crap jobs earlier in their careers, AIUI.
Again, I don’t know what they were counting on having him do. But neither does anyone from the story as I’d read it. It may even be they were only wanting him to come in to sit around the DPW and listen to the wind and rain while they waited for an act of God. Does it really matter, though? He was told to come in or face dismissal. Do you deny that the employer, especially in this circumstance, has a right to expect that for DPW workers?
(If you do, that’s fine. I’m not sure it’s a power they should have - but I don’t think it’s an unusual one.)