http://bep.gov/services/currencyredemption.html

Start with this above link if the bank won't take it. However, the money supply is a controlled amount and is not lowered by by old or damaged money. So you have the right to to get fresh money to replace the damaged money. Every day banks also send worn out money to the Fed to be replaced. There is a funny movie with Dianne Keaton called mad Money that makes light of the process.

Of course, the more you have of the bill, the better your chances of a faster exchange. Good luck!