How Compact Housing Development Can Help Solve Climate Change

November 19, 2020

A new report from Transportation for America (T4A) and Smart Growth America presents a compelling case for changing our land-use policies, including our housing policies, to cut down on greenhouse gas emissions and build a more sustainable future. The core of the case: Climate change can’t be solved with electric cars alone. We have to reduce demand for cars by building communities that don’t need them in the first place.

The key takeaways:

  1. Transportation is the single largest source of carbon pollution in the United States, and it’s growing, due in large part to more people driving longer distances in larger cars.
  2. Even under the most optimistic projections, electric vehicles will not replace gasoline cars fast enough to meet the emissions reductions targets we must achieve to prevent dangerous climate change.
  3. More compact communities that encourage walking, cycling, and transit — even in small communities and suburbs — can help reduce emissions from transportation.

The bad news: Pollution from cars is killing the planet. With such a simple proposition, one might expect that adding more cars to our domestic fleet of 270 million vehicles would not be considered a viable solution to the ongoing global climate crisis. But in the United States, taking on the ubiquity of cars is both a major technical and political challenge.

For example, Governor Gavin Newsom recently declared California would no longer allow the sale of gas-powered vehicles by 2035. Sounds good, but the problem: Most cars sold today will still be on the road in 15 years. That means a 2035 deadline for gasoline vehicle sales is a 2050 deadline to electrify the whole fleet. That’s too late for California to achieve its aggressive climate objectives. The solution proposed by T4A is identical to similar findings from the California Air Resource Board (CARB): We must reduce the total number of vehicle miles traveled (VMT).

Put simply: We need people to drive fewer miles in fewer cars.

T4A reminds us in this report that Vehicle Miles Traveled (VMT) are expected to increase by 1% each year. To date, fuel efficiency standards in new cars have struggled to reduce our emissions, because the savings have been canceled out by more driving. Even worse, the report includes evidence that “consumers’ appetite for SUVs will offset emissions savings from electric vehicles.”

Currently, transportation accounts for 28% of carbon pollution in the United States, with cars making up 59% of that share. If the pollution keeps growing, we’ll zoom-zoom right past our goals on climate change.

Across the U.S., per-capita VMT increased by 46% since 1980, and state transportation departments have added over 223,000 miles of new roadways in just the last decade. “We need to find ways to reduce driving rates altogether,” T4A reminds us, “because trends in the fleet makeup are sending us in the wrong direction.”

One key to solving this is looking at the disproportionate growth of VMT in urban areas. While urban populations grew by 32% since 1993, VMT in cities grew by 57% over the same period. As more sprawl development pushes people farther out from jobs and amenities, this continues to grow in a zero-sum competition with more sustainable modes of travel. T4A notes that “When high-speed driving is the goal of transportation investments, other modes of travel become impossible, and people are forced to drive more and farther.”

Sprawl also cannibalizes public services by exponentially raising infrastructure costs and depriving governments of tax revenue. Compared to sprawling communities, dense urban communities spend an average of $250 less per capita for the same amount of public services. It’s worth underscoring: “walkable, connected neighborhoods and communities cost one-third less for upfront infrastructure, saves an average of 10 percent on ongoing delivery of services, and generates 10 times more tax revenue per acre than conventional suburban development.”

Ironically, while the United States invests disproportionately on sprawl and highways, demand is only growing for transit-accessible and walkable urban living, which local governments make artificially scarce by prohibiting multifamily development. “Despite the demand for denser and more walkable neighborhoods, it is illegal to build anything except single-family detached houses on roughly 75 percent of land in most cities,” T4A observes. (Sound familiar?) By simply allowing more dense urban housing development, we could see people drive around 20-40% less. Otherwise, suburban sprawl leads to over twice as many carbon emissions per person.

T4A makes the case clear: “Whether people care about reducing their own emissions or not, by providing more opportunities for them to live where emissions are naturally lower per person, we can work within the market to help address climate change.”

With cities like Seattle, Portland, Minneapolis, Austin, Houston, and many others around the world working to reform their land-use policies to more closely account for VMT reduction as an explicit goal, it may be time for California to join the pack and align its housing policies with its climate policies.