Caltrans says starting tonight, the southbound on-ramps to the 99 freeway from Rosedale Highway will be closed for 25 days.These closures will take place during overnight hours as part of the Bakersfield 99 Rehab Project. A poster detour will be available utilizing Rosedale Highway, Oak Street and California Avenue. The SB-99 off-ramps at California Avenue will be closed as well.