Leaders of the Louisville group 8664 say the growing cost of materials underscores the need for more serious consideration of their proposed alternative to a new downtown bridge.The private group proposes replacing the downtown section of Interstate-64 with a parkway.“With construction costs up, 8664’s costs, we assume, would rise as well," says 8664 spokesperson Joe Burgan. "But since we do not build the downtown bridge and we do not expand Spaghetti Junction to the capacity the current project does, we probably would not grow in cost.”The Ohio River Bridges Project would build two new bridges and reconfigure downtown Louisville’s Spaghetti Junction. 86-64 members support an east end bridge but say their plan would eliminate the need for a downtown span and much of the other work. Opponents of 86-64 say it would cause more traffic problems than it would solve.