Alabama’s Jefferson County yesterday voted to raise sewer tariffs by 7.89 percent, more than the county’s bankruptcy plan had projected, and approved a deal to pay Lehman Brothers 75 cents on the dollar to settle missed payments on interest rate swaps, Reuters reported yesterday. Jefferson County in June filed a comprehensive negotiated plan to exit its $4.2 billion bankruptcy, the result of debts taken on in a costly overhaul and expansion of the county’s sewer system. With unseasonably cold and wet weather resulting in lower water usage, sewer revenues are down 5 percent, an unusual circumstance that Jefferson County expects to compensate with rate hikes, Eric Rothstein, a sewer rate consultant, told the Jefferson County Commission at its meeting on Tuesday. Monthly sewer rates will rise to a fixed rate of $15 per individual user, effective this fall, up from the current $10 month. From 2014, the rates will be hiked by 7.89 percent per year over four years. The bankruptcy exit plan had projected rate hikes of 7.41 percent.