The Marietta City Council on Wednesday approved refinancing a 2009 parks and recreation bond. Mayor Steve Tumlin said refinancing the $25 million bond at a lower interest rate will save taxpayers $1.27 million. City Finance Director Sam Lady said the lower rate will mean a 6.18 percent reduction in principal payments which run through 2030. since Marietta voters passed the bond in 2009, improvements have been made at 13 city parks.