Austin’s “Great Streets” are Great Problem

>By Jim Skaggs of COST

For many years, Austin’s City planning department and various factions within Austin have promoted and encouraged the City to change a number of its major downtown streets from their current one-way traffic configuration to two-way traffic. In recent years this effort has been titled the “Great Streets” program.

A number of studies and evaluations indicate changing downtown one-way streets to two-way have resulted in more accidents and delays for pedestrians and drivers creating increased congestion and pollution. Below are several references for these studies:

1. The following paragraph is from an article in the Institute of Transportation Engineers, ITE Journal, August 1998, titled:

‘One-way streets provide superior safety and convenience’
by John Stemley

The Summary paragraph is:

“Responsible officials who decide to ignore the many benefits that have and will continue to accompany a one-way street network will not be doing their constituency any favors by changing to a twoway network in their downtown area. They will be imposing increased accidents and delay upon drivers and pedestrians. Pedestrians will be inconvenienced where midblock crosswalks are removed. Congestion and air pollution will increase. Businesses and customers will find fewer curbside spaces available for parking or delivery. By changing to a two-way system, a large backward step will be taken which will result in a downtown that is less inviting than it is now.”

2. The Independence Institute’s Center for the American Dream published this Issue Paper:

‘No Two Ways About It:One-Way Streets Are Better Than Two-Way’
by Michael Cunneen and Randal O’Toole
Issue Paper 2-2005—February 2005

The Conclusion is:

“On just about any ground imaginable—safety, congestion, pollution, and effects on most businesses—one-way grids and one-way couplets are superior to two-way streets for moving people and vehicles. The idea that building pedestrian-deadly environments can create pedestrian-friendly neighborhoods is just a planning fantasy. Denver officials who truly want to create livable, safe environments for pedestrians and businesses should return transportation planning to the engineers, whose programs are grounded in reality, not fantasy.

In the long run, Denver and other cities need to rethink their support for urban planning. Why should cities employ members of a profession that advocates policies that reduce safety, increase pollution, and waste people’s time? It is time to return to the methods and vision of the engineer.”

3. Below is a paragraph from Vanashing Automobile (book by Randal O’Toole), Update #30, titled:

Should Cities Convert One-Way Streets to Two Way?

“By almost any measurable criteria — safety, pollution, congestion, and effects on most local businesses — one-way streets are superior to two way. The idea that two-way streets are superior because they are more pedestrian friendly is just a planner’s fantasy that disguises their real intent: to create an auto-hostile environment.”

4. Below is a paper by a Transportation Planner to Councilors Terry Whitehead and Brad Clark of Hamilton, Ontario, Canada. The transmital letter stated: “The bottom line is that enormous data exists demonstrating that a reversion from one-way to two-way flow vastly increases the accident rate, especially for pedesrians.”

Safety Benefits of One-Way Streets for Pedestrians and Vehicles

Many city studies were conducted from the 1930’s to the 1960’s of “before and after” conditions on streets converted from two-way to one-way streets. Almost universally these studies found that one-way streets had 10-40% lower accident rates than when previously two-way. Most significantly, pedestrian accidents declined far more, by 30-60% (see pages A-126; A-162, National Highway Safety Needs Study, Appendix A, Research Triangle Institute, March 1976 (DOT-HS-5-01069); Pages 7-2 to 7-8, “One-Way Streets and Reversible Lanes”, Synthesis of Safety Research Related to Traffic Control and Roadway Elements, Volume I, Research Triangle Institute, March 1976 (FHWA-TS-82-232), December 1982; Page 28, Dr. Charles Zegeer, University of North Carolina, “Pedestrians and Traffic-Control Measures”, National Cooperative Highway Research Program, Synthesis of Practice, #139, November 1988; and Chapter 10, Peter A. Mayer, Chapter 10, “One-Way Streets”, Traffic Control and Roadway Elements, Their Relationship to Highway Safety, Highway Users Federation for Safety and Mobility, 1971).

Regarding pedestrians crossing one-way streets, one leading safety expert noted: ‘”Conversion from two-way to one-way street systems has consistently been found to reduce pedestrian accidents” (Dr. Charles Zegeer, University of North Carolina, “Engineering and Physical Measures to Improve Pedestrian Safety”, from 1988 WALK ALERT Program Guide, National Pedestrian Safety Program). No measure undertaken by cities other than the installation of traffic signals has done more to reduce pedestrian accidents. Two-way streets typically have twice the pedestrian accident rate of one-way streets so they are definitely not “pedestrian-friendly”, as is widely being claimed. The value of one-way streets for pedestrian safety is well appreciated in the pedestrian capital of North America. The New York City DOT continues to convert more two-way streets to one-way flow and publicly claims it as a pedestrian safety measure, a claim well substantiated by their before-and-after data going back for decades.

Typical of the positive safety experience achieved by converting to one-way streets was that of Portland, Oregon. The City of Portland converted most of its Downtown area to one-way on March 1, 1950. Their before-and-after data (1949 versus 1951) on the streets that were converted found that vehicular accidents decreased from 6,127 to 3,361 (-45.1%). Adjusting for the increase in volume, the vehicular accident rate per vehicle volume (the standard measure) actually decreased 58.1%. The number of pedestrian accidents on the downtown streets that were converted decreased from 237 to 126 (-46.8%). Adjusting for the increase in volume, the pedestrian accident rate per vehicle volume actually decreased 59.7% (see Fred Fowler, ‘One-Way Grid System for Portland, Oregon’, Traffic Engineering, April 1953). This vast increase in safety was achieved even though volumes increased from 12,734 to 16,708 vehicles (+31.2%) and average speeds increased from 7.9 mph to 14.2 mph (+79.7%). The conversion to one-way aided bus transit, reduced energy consumption by all vehicles, reduced delays, and increased access to the downtown area.

In 1959, the Oregon State Highway Department published a report which summarized the overall impact of converting two-way state highway sections to one-way couplets through town and city centers in twelve smaller Oregon cities. The weighted average traffic accident rate declined 24% while the weighted average pedestrian accident rate declined 38% (see Oregon State Highway Department, A Study of One-Way Routings on Urban Highways in Oregon, Technical Report #59-4, April 1959).

Few cities that have made the mistake of converting one-way to two-way will release accident impact data on this change. Typically, studies favoring two-way avoid any real before-and-after data on vehicle or pedestrian safety or avoid the safety issue altogether. Two cities that have produced before and after data on conversions to two-way flow were Denver, Colorado and Lubbock, Texas. Both cities found that major increases in accident rates were the result of reverting to two-way traffic. In 1986 Denver converted seven streets on three one-way couplets. They found that average intersection accident rates increased 37.6% while average mid-block accident rates increased 80.5%. The City report noted that accident rates were up on all three couplets “as is expected with two-way operation” (see Pages 15, 23, and 29, City of Denver, One-Way Street Monitoring Study, Phase 1 Conversion Report, January 1990). Lubbock, Texas in 1995 converted two downtown streets back to two-way. Overall accident rates increased there 41.6% (see City of Lubbock, Main and 10th Street Accident Analysis, Before/After Study, 1998).

One-way operation permits much better traffic signal progression for smoother traffic flow. This results in traffic moving at regulated speeds with less stop-and-go driving. Less fuel is consumed and there is less air pollution. One-way signalized operation also tends to cluster traffic into “’platoons” with wide gaps between them. This makes it much safer and faster for cross street traffic, bicycles, and pedestrians to cross major streets.

Another benefit is in conservation of space. Because one-way streets move more traffic per lane than two-way streets cities with one-way systems need to devote less space to roadways. Four lanes of a one-way couplet carry as much traffic as a seven-lane two-way street. The main reason for this is that special left-turn signal phases are not required. At intersections a one-way approach requires only one signal phase – all vehicles can move.

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