Shoup Critique Of ITE Parking, Traffic Generation Manuals

Long the bible for planners, the ITE standards are misleading and reinforce car dependence

1 minute read

July 31, 2002, 2:00 PM PDT

By Abhijeet Chavan @http://twitter.com/legalaidtech


In a more popular version of a forthcoming article in the Journal of Transportation and Statistics, Donald Shoup chronicles the problems with the ITE Parking Generation and Trip generation manuals that have become standards for planners and transport professionals in the U.S. and even abroad. He demonstrates that their ostensible accuracy is unmerited and misleading; that average rates are most often presented despite lack of statistical evidence for any relation between floor area and trips generated; and, more profoundly, that the tables are based on assumptions of car dependent land use that the manuals help become self-fulfilling, as follows. Rates are derived from studies of peak parking demand and number of trips in suburban sites with ample free parking--lacking transit, pedestrian facilities, or TDM; these are then used to mandate the design of new developments, thus ensuring that parking in these will be free, and densities low (so traffic generated at the predicted rates does not overwhelm roads.) When such sites are surveyed in the future, they will, indeed, validate these rates. Voila!

Thanks to Yaakov J. Garb, ITDP

Wednesday, July 31, 2002 in University Of California Transportation Center

portrait of professional woman

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

Cover CM Credits, Earn Certificates, Push Your Career Forward

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

July 16, 2025 - Diana Ionescu

Green vintage Chicago streetcar from the 1940s parked at the Illinois Railroad Museum in 1988.

Chicago’s Ghost Rails

Just beneath the surface of the modern city lie the remnants of its expansive early 20th-century streetcar system.

July 13, 2025 - WTTV

Blue and silver Amtrak train with vibrant green and yellow foliage in background.

Amtrak Cutting Jobs, Funding to High-Speed Rail

The agency plans to cut 10 percent of its workforce and has confirmed it will not fund new high-speed rail projects.

July 14, 2025 - Smart Cities Dive

Worker in yellow safety vest and hard hat looks up at servers in data center.

Ohio Forces Data Centers to Prepay for Power

Utilities are calling on states to hold data center operators responsible for new energy demands to prevent leaving consumers on the hook for their bills.

July 18 - Inside Climate News

Former MARTA CEO Collie Greenwood standing in front of MARTA HQ with blurred MARTA sign visible in background.

MARTA CEO Steps Down Amid Citizenship Concerns

MARTA’s board announced Thursday that its chief, who is from Canada, is resigning due to questions about his immigration status.

July 18 - WABE

Rendering of proposed protected bikeway in Santa Clara, California.

Silicon Valley ‘Bike Superhighway’ Awarded $14M State Grant

A Caltrans grant brings the 10-mile Central Bikeway project connecting Santa Clara and East San Jose closer to fruition.

July 17 - San José Spotlight