As a man of the cloth (or not) would I first spend a lot of money on an illegally installed, unpermitted plumbing system and deliberately post no warning, so that I could ambush the homeless in their sleep and wet them and their winter clothes and sleeping materials down, in winter, (or summer)?
I wouldn't do that, I have never handled my problems with the homeless like that.
The lack of warning may have been an oversight. Or maybe they naively thought that these guys were as smart as any stray dog.