San Francisco's Chinatown has three construction projects happening, all less than a mile of each other, in the next couple of years. Demolition is already underway at Portsmouth Square. Crews will soon start upgrades to the Chinatown Public Health Center and Chinatown Branch Library. Watch NBC Bay Area News free wherever you are WATCH HERE WATCH HERENBC Bay Area got a look behind the construction fences at Portsmouth Square. Then, on the third weekend, a full closure of the Broadway tunnel will take place for upgrades to the Chinatown Public Health Center.