1/ Let's take a deeper dive into the completely bonkers TxDOT claim that expanding I-35 through AUSTIN will only increase GHG emissions by 14 percent over the baseline no-build scenario.
The claim hinges on very strange VMT results.
2/ First, we need to understand the scale of this project. It's an absolute beast. 365 FEET OF ROW!! Yellow = mainlanes; Green = frontage roads; Light Blue = untolled managed lanes.
But don't worry because the Dark Blue is a quiet, low-stress shared-use path.
3/ The justification for the expansion is that I-35 is terribly congested (TxDOT says the #3 most congested in the state) and that there will be even more driving/travel demand in the future.
Standard stuff.
4/ If a highway is already congested & you expect sustained regional growth (TxDOT estimates 1.5% compound annual growth), then expanding the highway will mean LOTS more driving compared to the no-build, right?
5/ According to TxDOT, no. This graph is a doozy. First, EV adoption will dramatically improve air quality. This is why the 2023 baseline (far left vertical bar) for Mobile Source Air Toxics (MSATs) drops in the out years. So far, so good.
But then it gets weird.
6/ VMT (shown by the brown line) under the no-build and build scenarios will be the same. What? VMT will be the same 1.1B miles for the no-build and build scenarios in 2050. That's farcical.
7/ Stated differently, according to TxDOT, VMT will increase by 37% (800M to 1.1B) from the 2023 baseline through 2050, but there will be no difference between the VMT of the build and no-build alternatives.
That's bananas.
8/ The weirdness doesn't end there. TxDOT is widening I-35 in three segments covering 27 miles. That makes sense from a construction standpoint. But TxDOT breaks the VMT analysis up as well.
Um, what?
9/ This approach defies common sense. All but 1.5 miles of the 27-mile widening lies within the City of Austin. Why would TxDOT model each segment independently. They certainly won't function independently.
10/ And this brings us back to where we started. When you assume VMT will be equivalent between the build and no-build, you end up with the bonkers estimate that GHGs will be equivalent too.
11/ Federal law allows USDOT to delegate responsibility for NEPA to state DOTs. TxDOT entered the program in 2014 and extended in 2019 for another 5 years.
Results like these show FHWA should review TxDOT's NEPA Assignment authority.
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