New laws in California and Oregon—California’s Sustainable Communities and Climate Protection Act (SB 375) and the Oregon Sustainable Transportation Initiative (SB 1059)—have made them the first states in the nation to try and reduce greenhouse gas (GHG) emissions using the transportation planning process.

A new NITC report coauthored by Keith Bartholomew and David Proffitt of the University of Utah evaluates how these pioneering laws have changed local planning processes in each state. Under these laws, metropolitan planning organizations (MPOs) must include climate goals in their regional transportation plans; coordinating land use and transportation infrastructure in a way that aims at reducing per capita GHG emissions.

"The MPOs have to show how, in the future, they could accomodate population growth, new housing and new transportation infrastructure, while reducing per capita greenhouse gas emissions," Proffitt said.

Although MPOs are in charge of creating regional plans, the authority to allocate land uses is held by each municipality.

"Conventionally, MPOs don't have authority over land use, so they don't consider a lot of changes to land use. Under the new laws, they have to think about the way land use impacts transportation infrastructure, and the metric that they use to do that is greenhouse gases," Proffitt said.

The municipality, however, still has the final say on implementing the MPO's recommendations with regard to land use. The laws in Oregon and California were therefore constructed with incentives (carrots) and deterrents (sticks) built in to encourage municipalities to follow the regional plans with their embedded climate goals.

The strategies to encourage compliance vary.

In California, for example, any transportation or housing project that is consistent with the sustainable communities strategy can either get streamlined approvals under the California Environmental Quality ACt (CEQA), or can be exempt entirely. This exemption saves the city time and money on environmental impact studies.

Conversely, non-compliant cities run the risk of being sued. Under the new law, not meeting the regional plan's goals is considered grounds for a lawsuit.

Bartholomew and Proffitt looked at regional transportation plans from every MPO in both states looking for insight into the laws’ effectiveness at changing development patterns in a way that reduces GHG emissions. "Cities change very slowly. So if we want to know whether these laws can be policy models for other places, we have to find a different way to measure what they're doing and whether they're working. What we've decided to do is to look at the plans themselves," Proffitt said.

Overall, their findings indicate that SB 375 and SB 1059 have led to a greater focus on climate change in regional transportation plans. While the trend is pointing in the right direction, there is still substantial room for improvement; the increases in plan quality are not universal for all regional transportation plans. Some plans even showed less of a focus on climate goals after the implementation of the new laws.

These variations raise interesting questions for future research.

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