There is a longstanding plan to divert traffic away from the Alameda and our neighborhood, and would include using Coleman as main access to downtown and the Arena from 880. Coleman is planned to be widened to six lanes and also Autumn would connect Coleman to Park. Last year the railroad crossing next to Target at the Marketcenter was put in, and construction for Autumn Parkway from the railroad tracks to Julian will get underway in September 2013, expected to last 12 months. This will then complete only the first phase, aka "the Herhold zigzag" where you would drive South on Autumn from Coleman to Julian, turn right (West) on Julian, and then left (South) back onto Autumn to pass the Arena.
More information about The Alameda Improvements can be found at: http://www.sjredevelopment.org/TheAlamedaTransportationImprovements.htm
The following links are to the final drawings for the 1st phase improvements on The Alameda. Look for this project to get started in the coming months.