California Law Ends Road Widening Mandates

Housing developers will no longer be required to dedicate land to roadway widening, which could significantly reduce the cost of construction and support more housing units.

1 minute read

September 25, 2024, 12:00 PM PDT

By Diana Ionescu @aworkoffiction


Aerial view of low-rise neighborhood in Los Angeles, California.

A Los Angeles law takes a piecemeal approach to road widening, calling for road expansion in front of new developments. | Unwind / Adobe Stock

Among the raft of bills signed by California Governor Newsom last week is Assembly Bill 3177, which prohibits local governments and agencies from requiring road widening next to new housing developments to achieve higher traffic flow, known as “level of service,” or “to achieve a desired roadway width.”

Under the new law, local governments would need to provide “substantial evidence” to require setting aside land for new roadway space, explains Melanie Curry in Streetsblog California. The law explicitly calls out a Los Angeles city law that calls for piecemeal “spot widening” in front of new developments, which often results in a zig-zag pattern that doesn’t improve traffic and eliminates thousands of square feet of land that could have been used for additional housing. While AB 3177 will eliminate this requirement for residential projects, the Los Angeles law will still apply to other types of developments.

According to the bill’s analysis, “A 2016 research study published in the Journal of Transport and Land Use found that road widening requirements in Los Angeles can cost developers over $10,000 per unit, resulting in up to hundreds of thousands of dollars being added to projects subjected to these requirements in certain instances.” 

Monday, September 23, 2024 in Streetsblog California

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