MILWAUKEE (CBS 58) -- Repairs are underway on Miller Park's retractable roof. 

Two cranes were brought in to help with the work. Crews have to replace equipment that helps the roof open and close. It's the first significant maintenance project for the retractable roof since 2006. 

"There's ten drive tracks up there that open and close the roof. One of the wheel bearings started making a clicking noise, we're replacing that bearing. We're inspecting the old bearing to see what the issue was if any," said Miller Park District Executive Director Mike Duckett. 

The work should wrap up in less than two weeks. 

The maintenance project is expected to cost nearly $1 million.