Which destroys more trees, HSR or floodwalls?

Bottom line, in our local cities: 

Caltrain electrification: 300 trees destroyed along 5 miles of track (60 trees per mile)

100-year floodwalls: 1600 trees destroyed along 2 miles of creek (800 trees per mile)



With Caltrain electrification (a step towards high sped rail) going up, thousands of trees will be going down. Estimates are that about 2,220 trees would be removed along 50 miles of track between San Jose and San Francisco. About 45 trees per mile. The report notes that Caltrain is exempt from local regulations guarding tree removal because it is a federally regulated rail carrier and thus benefits from an exemption in the Public Utilities Code. Source: MV-Voice: Caltrain Plan Would Fell Trees and Caltrain Electrification Project Draft Environmental Impact Report 

How does that compare with tree losses for 100-year floodwalls?

We counted about 100 Significant Trees Endangered along 1/4 mile of one side of the creek bank. That's about 400 trees per mile on one side. If floodwalls become the option selected for 100-year flood protection, about 4 miles of creek bank would be at risk for oak woodland destruction, about 1600 significant trees. Counting both sides, 1600 trees destroyed along 2 miles of creek (800 trees per mile)

 Almost everybody 100-year floodwalls are an ecological and visual disaster. Almost everybody agrees that they will never be built. But they are one of the only ways to convey the 100-year flood in a widened creek channel below Middlefield Road. 

 Upstream measures are the only solutions to this problem. 

 With upstream measures, there is not reason to build 100-year super-capacity-bridges at Pope/Chaucer and Newell. Pope/Chaucer should be replaced, but with a much smaller 40-year capacity bridge. 


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