On November 4, the good people of Jefferson County, Alabama, like so many other Americans, will help elect the next president. They will also voice their opinion about who should pay for their drains.

The $3.2bn bill for a new sewer system threatens to push Jefferson into the largest municipal bankruptcy ever, beating easily the Orange County, California, default of 1994. Jefferson's predicament sums up the growing crisis in US local finance. Investing in new pipes to clean up its rivers, the county turned to Wall Street for innovative financing. Unusually, it was all done at variable rates, about two-thirds through auction rate securities, all hedged with interest rate swaps. Now, with ARS about as popular as raw sewage, Jefferson's costs have soared.