SF's Millennium Tower
by Ruben Rodrigues
1. San Francisco's beleaguered Millennium Tower is still sinking
1.1. The northwest corner descended at least 18 inches into the bay fill at Mission and Fremont streets
1.1.1. A $100 million fix for the 645-foot-tall residential building will likely begin in the fall
2. The blue-gray glassy modernist tower, completed in 2009 at 301 Mission Street, is the tallest residential building in the city
2.1. Won numerous engineering awards upon its construction
3. In May 2016 residents were informed that the main tower that housed their luxury condos was sinking.
3.1. The foundation at 301 Mission was built into deep, dense sand but not bedrock, unlike most downtown towers
4. The building's homeowners association sued the main contractor Webcor and the developer Millennium Partners
4.1. The city of San Francisco also filed suit against the tower's developers
4.1.1. All suits were later consolidated into a global agreement that is expected to be finalized next month.
5. As of 2018 the sinking had increased to 18 inches with a lean of 14 inches.
5.1. Residents reported hearing various "creaking sounds," and then a "popping sound" at around 2:30 a.m. on the morning of Sept. 8, 2018.
5.1.1. Concerns that the creaking, popping and cracking were another symptom of the structural failure grew. A report conducted on behalf of the tower’s managers, blamed the crack on an “exterior impact,” but gave no indication as to what might have struck the window.
6. Hamburger, the senior principal engineer at Simpson Gumpertz Heger, revealed a final resolution to the Millennium Tower's sinking problem that involves underpinning the building.
6.1. The solution, likened to putting a bumper jack next to a flat tire, will involve the installation of 52 piles along the north and west sides of the tower
6.1.1. The fix will cost about $100 million.