100 feet of subway track? I wish I could get those rates. NYC's latest Second Avenue Subway budget is $6.3 billion for 1.5 miles, or, about $800,000 a foot. You can get 25 feet of subway track.

California's not quite that bad, but, it's close to that bad. The Downtown Extension for Caltrain is $3 billion for a mile. SF's Central Subway is $923 million a mile. So sure, you can get about 114 feet of subway, but it'll be the short little LRVs and not like BART or anything nice-ish.