The changes that are being suggested could not only financially cripple some traffic engineering agencies but could also cripple traffic flow in large metro areas. Knoxville if relatively small in comparison to Atlanta, Chicago, New York, etc., but could experience very real problems with trying to accommodate these recommended guidelines. The decrease in walking speed could cause very real problems for area that already have long clearance times in heavily congested areas due to roadway designs that provide long crosswalks, e.g., new designs on TDOT I-40 project create one crosswalk that is 140 feet long. The required pedestrian clearance interval based on 4.0 ft/sec walking speeds would be 33.5 seconds which will cause problems with signal timing. The increase for 3.5 ft/sec walking speed would be to 38.3 seconds. Five seconds can cause real problems with signal timing in already congested areas. For 3.0 ft/sec walking speed the required time would be 44.7 seconds. The time increase may seem short but in real world situations can mean the difference in moving traffic and long queues during peak times. Take into account this is for Knoxville. The other things like increased crosswalk widths, ramp modifications, new signal equipment and crosswalk modifications are not only funding but man-hours in City's with staffing problems already. The cost of new pavement marking could be absorbed if the guidelines provided adequate time for these to be programmed into already existing schedules but usually they do not. These schedules are sometimes as long as ten years due to staffing and funding needs to accomplish. The new equipment is expensive and also has a maintenance issue which must be addressed if they are to operate properly into the future. Most changes of this nature do not consider and forget that not only do these items need to be funded initially but also need to be funded for future maintenance. I just wanted to express my opinion and concerns. I also want you know that I understand the need for these types of changes as well. But if we destroy the infrastructure in the process, what have we really accomplished for anyone of our citizens. Please consider these long and hard before making changes that may cause more harm that good that they accomplish. Thank you. Ernie

Ernie L. Pierce III
Traffic Engineering
City of Knoxville

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