Outstanding water bill after a property has sold.

[Paul Winka]

If a seller sells his rental property, then the buyer discovers after closing that there is an outstanding water bill from the property in the seller’s name (only one meter on a multifamily), what can/should the seller do?

I suppose the buyer would be SOL because he didn’t perform proper due diligence and verify the utilities were current. The buyer would have to pay the bill, similar to what might happen if there are title issues? The right thing to do would be for the seller to pay it, but other than guilt over being unethical, is there any reason the seller should pay the debt?