Has Seattle Solved the Science of Parking Demand?

Parking regulations are generally formulated as uniform standards that apply to hundreds or thousands of parcels equally, often resulting in overbuilt supply. But what if planners could anticipate the parking demand down to the parcel?

1 minute read

April 27, 2013, 5:00 AM PDT

By Jonathan Nettler @nettsj


As Emily Badger reports, Seattle's King County Metro Transit agency, with the help of the Center for Neighborhood Technology and the Urban Land Institute Northwest, have been working on solving the parking supply vs. demand conundrum and may have achieved a significant breakthrough.

"They've spent the past year trying to measure exactly which factors dictate residential parking demand around the region, in downtown Seattle, in urban neighborhoods, in the suburbs and even farther out. The result of their efforts is this Right Size Parking Calculator web application that can estimate parking demand down to a single parcel of land (and that should be replicated in other cities)," she writes.

"The idea is that developers might use the tool when planning a project," she adds, "but also that local governments might consider this data in updating their parking regulations. King Country is agnostic about what they come up with."

"The name 'Right Size' is very conscious because we don’t want to just say 'in all cases there should be less parking,'" says Ron Posthuma, the assistant director of the King County Department of Transportation. "In some cases, maybe there should be more."


Friday, April 26, 2013 in The Atlantic Cities

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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