Fire Watch for Main Station Security?

We have over 500 membership numbers.  There are 365 days in a year. If every membership number were assigned *one* day per year in which they would stand "fire watch", basically walking the docks and parking lot from dusk until dawn, we would have the equivalent of a security guard without any need to raise dues or moorage to pay for one.

Fire watch would not be expected to confront bad guys, merely call the cops when something is going down...