Here’s what it will take for Greater Washington to cut climate pollution from cars and trucks fast enough

This week the region’s local officials and transportation agencies are facing the stark reality that they must quickly adopt major policy changes in the next several years if Greater Washington is to achieve its climate change target.

The National Capital Region Transportation Planning Board (TPB), whose board includes local and state government representatives, presented the draft findings of its Climate Change Mitigation Study. The analysis by consultant ICF showed that the region must both:

• Cut per-person driving by up to 20% by 2030 through shifting travel to other modes, bringing jobs and new housing closer together and near transit, making communities more walkable and bikeable, pricing congestion and parking, and continuing telework; and
• Meet or surpass the Biden administration goal for electric vehicles, with half or more of new cars, SUVs and pickups sold being electric by 2030.

This scenario study largely confirms previous national analyses and a report by the Coalition for Smarter Growth, where I work. The TPB’s report comes as Greater Washington and the world have only nine years remaining to meet our region’s critical target of reducing greenhouse gas emissions 50% compared to 2005 levels. The target, adopted by TPB and the Metropolitan Washington Council of Governments, is consistent with United Nations and Biden Administration goals to keep global warming to the manageable level of 1.5 degrees Celsius.

What’s new in this latest regional climate study?

A year ago the Washington region adopted a new climate plan for 2030, which included transportation strategies and an electric vehicle goal, but didn’t quantify how much the region would also have to reduce driving. Prompted by advocates like the Coalition for Smarter Growth and local elected officials, TPB agreed to undertake a study to provide specifics.

Initial results presented this Fall showed that Greater Washington would have to immediately force every car buyer to invest in an electric vehicle — a hypothetical impossibility — to sufficiently reduce its climate pollution from cars. This is because regional transportation plans largely maintain current levels of auto-dependence and assume continued sprawl and lack of sufficient housing options near jobs and transit.

More detailed scenario results presented this month showed the menu of realistic options that could succeed (numbers in beige below) – or fail (white numbers) – in implementing the region’s climate plan:

The three most ambitious “COMBO” scenarios would meet the regional climate plan level of reducing greenhouse gases from cars and trucks. These combine both the vehicle technology (VT) and mode shift (MS) strategies and also include the less impactful but still helpful transportation systems management and operations improvements (TSMO) that help smooth traffic flow.

While the most aggressive vehicle technology scenario, involving very ambitious electric vehicle sales goals, could in theory provide sufficient reductions on its own, this would depend on the Washington region surpassing California, the nation’s clear leader in electric vehicle adoption. It also would only happen under an accelerated “Clean Grid” scenario that speeds up the region’s transition to 100% carbon-free electricity by 2035, 10 years sooner than current policies.

What are the mode shift strategies?

The mode shift scenarios paint a picture of the types of policies that the region must implement.

• The base scenario (MS.1) uses a comprehensive approach of transit-oriented and walkable land use for new development, meeting the region’s adopted goals to build more housing near transit and make it affordable, improving transit travel times and access to stations, reducing transit fares, pricing parking in job centers, and assuming a continued high level of telework (25% of the region’s workers on a given day).
• The next scenario (MS.2) adds road pricing to the base – a regional per mile road usage fee (starting at 5 cents per mile) combined with a $10 fee to drive into downtown DC.
• The most aggressive scenario (MS.3) takes the above strategies further – free-fare transit, faster transit travel times, and a 40% telework rate (which equates to about 80% of all office workers on a given day).

Given the challenges of the most aggressive scenarios (VT.2 and MS.3), it appears that some hybrid of COMBO.2 and COMBO.3 would be the most feasible of the scenarios that sufficiently cut greenhouse gases. This suggests that road usage fees or congestion pricing are a critical component of any successful transportation-climate strategy in combination with land use changes and other mode shift strategies.

The full Scenario Analysis Findings draft report provides detailed descriptions of the scenarios, their assumptions, and further results.

The good news

Most of these policies have been modeled before by TPB and by WMATA and shown to provide a host of benefits to residents, workers and all modes of travel. Greater Greater Washington advocacy staff hosted experts on congestion pricing who likewise illustrated the economic, health, sustainability, and travel benefits of this tool, which has been successfully implemented in several of the world’s major cities and is being studied by many US cities. Plus, with the nation’s auto fleet shifting to electric vehicles, road user fees will be needed to replace the gas tax.

What’s next?

Local elected officials and transportation agency leaders on the board of TPB will discuss the results Wednesday at their monthly meeting.

Key questions for them are:

• How will TPB translate the findings of the climate change mitigation study into real-life initiatives to put in their Visualize 2045 long-range transportation plan next year?
• Will TPB members remove some of their proposed $32 billion in highway expansion projects, given the well-documented additional driving that these induce?
• How will the study findings shape other regional efforts, like the road-heavy Northern Virginia TransAction transportation plan and 6-year funding program?
• Will local jurisdictions enact the necessary land use policies, like building more housing near transit and stopping sprawl along the region’s edge, to support the transportation mode shift strategies?