Flood trouble

Should your landlord be required to replace your carpet?  That depends.
The obvious questions that I would have are whether the water was potable or raw sewage.  If indeed you had raw sewage on your carpet, then yes, most likely your landlord should replace the carpet if it can’t be properly cleaned and restored to original condition.  However, if the carpet soaked up water that did not have any sewage, well, there wouldn’t really be a reason for carpet replacement.
As for your renter’s rights– well, you are entitled to a safe living environment.  There is no law that will automatically require the landlord to replace your carpet.  The common myth that rental laws say what should be done is nothing more than a myth.  Check it out yourself.  There is a link to your states rental laws via the RPA Renter’s Right page.  You will see that the actual statute dealing with rental problems is vague and not specific to any one problem.
You have the right to dispute any decision your landlord makes concerning your rental.  It doesn’t mean you will get what you want.