Cobb County will issue about $135 million in bonds to help pay for a deep sewer tunnel that will serve south Cobb.
Commissioners approved the bond issue last week and awarded the bond work to Merrill Lynch. The county will pay 3.74 percent interest, county spokesman Robert Quigley said.
The deep tunnel, which is under construction near Mableton, will stretch 6.5 miles and will help the county prepare for future growth.
Water and sewer fees will be used to repay the money.
Cobb will put $65 million of the bond money toward the sewer tunnel and $35 million toward upgrades at the south Cobb treatment plant, Quigley said. The county will make upgrades to meet tightened standards for treating sewer water before releasing it into the Chattahoochee, he said.
The rest will be spent on other water system projects.
Cobb County’s water and sewer bonds received a triple AAA rating last month from all three major rating agencies: Moody’s Investment Service, Standard & Poor’s and Fitch Ratings. The high bond ratings mean the county will get a lower interest rate when it borrows money, county officials said.
Only three water and sewer systems in the country that are self-funded have the triple AAA rating. In addition to Cobb County, they are Palm Beach, Fla., and Chesterfield, Va., county officials said.