So here's a clear case of putting undue stress on the indigent who don't pay a water bill on time: you get a reminder every week, to the tune of $10 each time (adds to your balance), but if you mail your check between two such letters, they grind on you to pay that additional late fee, even if the check is post marked and cashed in between.
What they say on the phone is you have to phone them and ask for a waiver, don't understand that a check in between should have bought freedom from any additional penalty charge.
Most "down and outers" won't dare stand up to a bureaucracy so it's up to those of us with some fight in us still, to point out this kind of petty abuse (it all adds up), this kind of nickle and diming that counts on (presumes) a "grin and bear it" attitude, is not modeled on serving proud Americans willing to stick up for themselves.