The Louisville Metro Council has approved a bond issue for the Metropolitan Sewer District.MSD requested a $330 million bond that would be guaranteed by the city. The money will mostly go toward federally-mandated sewer improvements. The district plans to repay the bond through a 6.5 to 7 percent rate increase over the next three to four years.MSD sought and won a $180 million bond issuance for similar improvements last year. Council majority caucus spokesperson Tony Hyatt says the frequent rate hikes are uncomfortable, but they could be worse."MSD had pretty much told us if they had wanted to, they could've had huge rate increases in double-digits, but in these tight economic times, they thought it was best to go for the rate increases they needed at the time to keep the projects going," he says. So while no one likes a rate increase, we are under a federal consent decree to correct the problem."The council approved the bond issue at its regular meeting Thurday evening.