Part One: The Two-Lane Alternative, a Modern, Workable, Proven Approach

The Two-Lane Alternative Modern Roundabouts

The Pennsylvania Department of Transportation (PennDOT) is preparing a Draft Environmental Impact Statement (DEIS) for improvements to Pennsylvania Route 41 (PA 41). The basic transportation needs for PA 41 were identified by PennDOT as safety, capacity to serve future traffic volumes, deteriorated infrastructure, and modal relationships. The conventional PennDOT improvement alternatives address the identified needs by widening PA 41 to four lanes on the existing alignment from Route 7 to Route 926 except within the historic districts of Avondale and Chatham, as well as adding four high-speed, limited access bypasses around Chatham and Avondale.

In conjunction with professional transportation engineers and consultants, Smart Mobility, Inc. and Glatting Jackson Kercher, S.A.V.E. has developed a Two-Lane Alternative Plan for addressing the needs of PA 41. This plan would maintain the corridor as a two-lane road, with safety and intersection improvements that will result in a safe, attractive road with adequate capacity to meet future traffic volumes. The two-lane plan described in our 2002 Smart Mobility report (4MB pdf) addresses the identified transportation needs of PA 41 while substantially reducing environmental impacts, secondary impacts, and costs compared with the six-lane PennDOT proposals. The two-lane plan takes advantage of the greater design flexibility afforded state transportation agencies since the passage of the Intermodal Surface Transportation Efficiency Act (ISTEA) in 1991, and specifically allowed in the National Highway System legislation. The two-lane plan uses proven, innovative and attractive intersection designs and cross-section treatments.

Meeting the Project Needs

The two-lane alternative addresses the four basic needs of the project of safety, traffic capacity, infrastructure, and modal relationships.

Safety

The safety of PA 41 is primarily addressed through reducing the potential for traffic conflicts, and moderating travel speeds with traffic calming techniques, thereby reducing the potential for injuries. The safest form of intersection traffic control, the modern roundabout, is used at the most heavily traveled intersections. Between intersections, several concepts for typical cross sections are proposed that will moderate speeds, reduce potential traffic conflicts, and improve safety for all the road's users, including farm vehicles, pedestrians, and carriages.

Capacity

Using standard measures of road capacity, rather than road operating speeds, the two-lane plan provides ample capacity to meet the future traffic volumes projected by PennDOT and the Delaware Valley Regional Planning Commission (DVRPC). The conclusion that two lanes provide adequate future capacity differs from PennDOT's conclusion that the six lanes are needed because PennDOT is using traffic operation measures that emphasize traffic speed rather than the more important concern of traffic capacity.

Modal Interrelationships

The proposed two-lane concept primarily focuses on traffic operations and design. However, the two-lane plan will be far more amenable to serve and integrate other modes of transportation. Pedestrians, bicyclists, farm vehicles, Amish carriages, and buses will have far better access to the important current and future land uses along the corridor, as compared to the six lane plans which highly restrict access to land uses. For example, transit buses that may be accessing a proposed new shopping center in New Garden would have to make a lengthy detour to the nearest grade-separated interchange to make a u-turn, in order to drop-off or pick-up passengers. The two-lane plan will enhance access for all modes along this important corridor, thereby encouraging alternative modes of transportation through increased safety and aesthetics.

Project Design Goals

There are several goals that were incorporated into the plan as the design was developed. First and foremost among these goals is to meet the project needs as described above, with the most important of these goals always being safety. The following design goals were also considerations in the project design.

Compatibility with Local and Regional Land Use Goals and Plans

The two-lane plan is designed to support and complement the local and regional land use plans and goals, as envisioned in ISTEA and National Highway System legislation. The 6-lane proposals of PennDOT work contrary to the region's goals of agricultural preservation, compact development, and more choices in transportation.

Minimizing Primary and Secondary Environmental Impacts

Major transportation improvement projects such as the PennDOT 6-lane proposals for PA 41 have numerous secondary effects, such as induced traffic, catalyzed development, increased stormwater issues, increased air pollution, and increased air pollutant emissions.

Catalyzed development results from the reduction in highway travel time making the project area more accessible to employment and services; thereby increasing it's attractiveness for development. The two-lane plan will result in only minimal changes in travel time, avoiding the destabilizing increases of accessibility and development pressure. The current land use impact study, being conducted by the Chester County Planning Commission, may provide a basis for estimating induced development. It appears that the DVRPC has not considered the effect of induced development from the proposed PennDOT six-lane plans.

Induced traffic results from additional travel that can be attributed to the change in conditions from a faster or wider highway. Examples of induced traffic include re-routing of current trips to use the new road, longer trips to more distant destinations, new trips, and trips made during the peak hour rather than during off-peak times. Because the two-lane plan addresses the needs of the project without altering regional travel times or accessibility, it will result in very little induced traffic. The induced traffic from the six-lane plan poses problems throughout the corridor, and especially severe impacts of traffic safety and congestion to the northern end of the Route 41 corridor. These impacts will be negligible with the two-lane plan.

Air Quality Impacts will result from both the increased volumes of traffic that will be drawn to the expanded road, especially trucks, and from the higher speeds that may result from the improvement. The two-lane plan will minimize impacts of air quality to the Wilmington area, as it will minimize induced traffic and maintain moderate, less polluting traffic speeds. By utilizing a series of modern roundabouts, air emissions will be greatly reduced, as traffic experiences less delay and greatly reduced stopping and restarting. The project area has experienced air pollutant standard violations routinely, and the Wilmington region particularly has had a difficult time demonstrating conformity with the Clean Air Act. The two-lane plan maintains traffic speeds in the range where NOx emissions are reduced, compared with the higher emissions generated at higher speeds anticipated under the four-lane plan of PennDOT. The PennDOT six-lane plan will also result in increases of emissions from diesel trucks, as it is specifically designed to encourage the use of Route 41 as a trucking corridor, and will bring with it increased emissions of particulates, which have especially severe health effects.

Traffic Congestion Impacts result from traffic generated by the project having impacts beyond the project boundaries, where there is inadequate capacity to meet the additional traffic. The Wilmington Area regional transportation plan shows that the highway corridors that lead to PA 41, including DE 41 and DE 7, are already congested. Furthermore, the Wilmington area's future traffic projections at the DE/PA state line are lower than those used by PennDOT/DVRPC, calling into question the higher traffic forecasts used by PennDOT to justify the six-lane highway alternatives. Again, a series of modern roundabouts will vastly improve traffic flow and congestion.

Conclusions

The Two-Lane Alternative With Roundabouts provides a safe, feasible, sustainable alternative to address the deficiencies and to meet the future needs of the entire Route 41 corridor. The traffic will be accommodated with minimal impact to the environment, and at a cost of just a small fraction of PennDOT's proposed six-lane alternatives. The result will be a safe, attractive road that supports the region's planning and environmental goals.

The conceptual Two-lane Alternative Plan is currently undergoing refined design and analysis by PennDOT, in preparation for the publication and release of the Draft Environmental Impact Statement. The analysis is expected in early 2004. Citizens who are concerned about the issues outlined above and who feel that the Two Lane Alternative makes sense are encouraged to let their elected officials know.

Read the full report prepared by Smart Mobility, Inc. for S.A.V.E. This is a large (4MB) PDF file.Click here to download.

Traffic Calming

Reports on traffic calming show a reduction of the frequency of accidents of 72% and a reduction of serious injuries of 78%. Click here for more reports.

What is Traffic Calming?

According to the Institute of Transportation Engineers (ITE), traffic calming is "the combination of mainly physical measures that reduce the negative effects of motor vehicle use, alter driver behavior and improve conditions for non-motorized street users."

Traffic calming measures should not be confused with route modifications, traffic control devices and street scaping. Traffic control devices, notably, stop signs and speed limit signs, are regulatory measures that require enforcement. Traffic calming, by contrast, is intended to be self-enforcing.

The immediate purpose of traffic calming is to reduce the volume and speed of traffic to acceptable levels. Reductions in traffic speed and volume, however, are just means to other ends, such as traffic safety and active street life. Different communities undertake traffic calming for different reasons. The following are various reasons communities undertake traffic calming:

• Reduce through traffic
  
• Reduce truck traffic
  
• Reduce occurrence of excessive speeding
  
• Reduce noise, vibration, and air pollution
  
• Reduce accidents
  
• Provide safer environment for pedestrians

The History of Traffic Calming - where did it start?

The following is from a report written by Timothy Stillings, AICP and Ian M. Lockwood, P. Eng., entitled, "West Palm Beach Traffic Calming: The Second Generation," to fully understand traffic calming, one should understand the history of traffic calming. The idea of traffic calming is certainly not new.

It began in the 1920s in Europe; at about the same time the automobile was becoming popular. In 1928, the British Parliament published the "Road Vehicle Regulation Bill," suggesting that speed humps and other measures be used to slow drivers. In 1938, Alker Tripp, a former Assistant Commissioner at Scotland Yard, wrote his book, Road Traffic and Its Control, which discussed the reduction of motor vehicle speeds to reduce collision casualties, giving pedestrians priority while maintaining vehicular access, all through modifications to the street. In 1963, Colin Buchanan wrote Traffic in Towns, in which he cautioned communities about the impact of the growth of motor vehicle traffic in urban areas, and offered recommendations to avoid it. Buchanan had the idea that, in urban areas, there "must be areas of good environment - urban rooms - where people can live, work, shop, look about, and move around on foot in reasonable freedom from the hazards of motor traffic... "

In the late 1960s in the City of Delft, The Netherlands, motor vehicle dominance led to a revolt against the automobile by angry residents. Completely fed up with the negative impacts of cars on their street and the lack of a remedy by the City, a group of residents tore up the brick pavement one night such that cars had to maneuver in a serpentine pattern at much slower speeds. The initiative did not close or even partially close the street, but forced drivers to behave differently, i.e., slower. Necessity is the mother of invention and consequently, the woonerf, "living yard," was invented. Later in 1972, the first officially sanctioned woonerf was built in Delft. This is commonly considered to be the birth of modern traffic calming.

In 1976, the Dutch Parliament passed legislation permitting the installation of woonerven and by 1983, more than 2,700 had been constructed. Surveys indicated that the majority of the population considered the woonerf attractive. They also reduced the number of injury-related collisions by 50 percent. The lower speeds also contributed to a decline in the severity of the crash-related injuries.

The woonerf concept was later replicated in Germany and termed Verkhrsberuhigung or "traffic tranquilization," later called traffic calming in English. Traffic calming in Germany became a widely accepted and successful transportation practice. The Germans then developed 30 kilometers/hour (19 mph) streets, which greatly reduced the cost of traffic calming when compared to the relatively expensive woonerven while achieving the benefits at about the same level.

Traffic calming rapidly spread through Europe, Australia, New Zealand, Japan, and most of the developed world. It has also been used in the United States and Canada. It was originally initiated through the efforts of community associations in the Northwest United States, but is now a transportation practice used by a rapidly growing number of cities and towns throughout the Country. The first generation of traffic calming programs were developed by Portland, Oregon, and Seattle, Washington, and later became the model for many cities, including the initial policy for West Palm Beach.

Other examples of traffic calming

Traffic calming is being used in many other places in the United States. The Route 50 Corridor Coalition in Virginia formed a citizens group to preserve and enhance the scenic, historic countryside bounding a 20-mile stretch of rural Route 50 in Northern Virginia's Piedmont. Key to this goal is traffic calming on Route 50. The Route 50 Corridor Coalition and area residents have created a nationally recognized traffic calming plan for 20 miles of historic Route 50. The plan is simple, inexpensive, and unanimously endorsed by local governments. It stresses safety, economy, and historic awareness. Project implementation is moving ahead. To find out more: www.route50.org

Newark, Delaware recognizes the benefits of traffic calming. In Newark, there were concerns regarding excessive traffic volumes and vehicles operating at excessive speeds, threatening the local quality of life and the health, safety and welfare of residents and visitors in the Old Newark area. See their plans at: www.wilmapco.org/studies/Newark/index.htm

For more information:

One of the very best websites on all aspects of traffic calming can be found at www.trafficcalming.org

For more on the concepts of traffic calming, visit Traffic Calming for Communities

or from the City of Portland, Oregon's Office of Transportation site on Traffic Calming.

Traffic calming could be used successfully on Route 41 and other community roads in southwestern Chester County.

PennDOT builds roads to accommodate more traffic, and greater speeds, which conflicts with the goals residents of southwestern Chester County and impairs their quality of life. Route 41 could be a safe, two lane road using traffic calming techniques. The whole 19 miles could be safe in a short period of time, for a tiny fraction of the cost of PennDOT's 4-lane expressway.

To illustrate how traffic calming could be used, S.A.V.E. has hired a nationally respected traffic engineer to suggest traffic calming measures for the areas of Route 41 that are threatened most by large volumes of traffic, especially tractor trailer trucks. The following photographs and renderings illustrate how this could be used:

S.A.V.E. has put together some renderings of how we think traffic calming could look in Avondale and Chatham, as well as at the intersection of Rts. 926 and 41. Click on the links below to see these renderings.

• Avondale
• Chatham
• Route 926 and Route 41 Intersection