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TR9701-CS 971002Sverdrup Civil, Inc. - Dallas, Texas Office 8150 N. Central Expy · Suite M-1150 · Dallas, TX 75206 · Tele: (214) 696-3433 · Fax: (214) 696-3499 MEETING MEMORANDUM NO. 13776-8 October 2, 1997 MEETING DATE: LOCATION: PARTICIPANTS: SUBJECT: September 16, 1997 Sverdrup Civil, Inc. 8150 North Central Expressway, Suite M- 1150 Conference Room Kathi Mullins Atul Patel Tony Tramel Jeremy Wyndham Gerry de Camp Doug Bowen City of Irving City of Coppell DeShazo, Tang & AssoCiates Sverdrup Civil Sverdrup Civil Sverdmp Civil Dallas County CMAQ Program Project 75 Progress Review Meeting 8 Discussion of Field Implementation of Timing Plans (Coppell): · Mr. Wyndham indicated that all three timing plans had been field implemented in Coppell. · Mr. de Camp noted that the traffic signal at the intersection of Belt Line Road, Denton Tap Road and Southwestern Boulevard is currently running lead-lag operation in the AM Peak with normal 5-section protected/permissive heads. This condition has a "yellow trap" associated with it unless changes are made either to provide the "Dallas Display" or to make the left-tums "protected only" during this time period. The controller at this location is capable of handling both of these improvements. · Mr. Wyndham stressed that one or the other of these improvements should be made to remove the "yellow trap" at this location. For capacity reasons, it would be preferable to upgrade the signal heads and make the wiring modifications needed to implement the "Dallas Display." Discussion of Signal Change Intervals: · Mr. Bowen discussed the process of calculating the various signal change intervals, using Institute of TranSportation Engineers' recommended practice along with field observations. · Mr. de Camp interjected that the numbers that are shown in the tables are slightly different from those provided to the City of Coppell for implementation on the Controller time sheets. It is up to the City of Coppell whether to change the numbers in the controllers to match the recommendations in the tables provided. Dallas County CMAQ Program Project 75 September 16, 1997 Page 2 Mr. Bowen explained that in general, the recommended clearance intervals were higher than the existing intervals in Coppell and lower than the existing intervals in Irving. In some cases, the recommended yellow clearance interval was longer than the value calculated using the ITE recommended practice. In many of these cases, this difference was offset by an all- red interval that was shorter than the calculated value. Thus, in most cases the recommended overall clearance interval (yellow plus all red) was very close to the calculated values. Mr. de Camp explained that in some cases, field observations and experience with traffic signal operations led to making recommendations for overall clearance intervals slightly less than the calculated values. He also noted that in every case, the recommended values fall within the Uniform Manual range of 3.0 seconds to 6.0 seconds. Mr. de Camp offered that the most important thing in setting the clearance intervals is that they are set for specific reasons, rather than just estimated. Mr. Bowen indicated that the passage time interval was set based on field observations, rather than calculations. Mr. Tramel stated that in his experience, different controllers have different definitions for passage time. Mr. de Camp stressed that all of the definitions in NEMA controllers are approximately the same. Mr. Patel asked whether the speeds used to set the intervals were the posted speeds along the corridor. Mr. Wyndham indicated that the speeds used for the calculations were not necessarily the posted speeds, but rather reflected more realistic approach speeds based on field observations and travel time runs. Ms. Mullins asked about the locations in Irving that showed Not Applicable for the pedestrian timings. Mr. Bowen explained that at these locations, neither pedestrian push buttons nor pedestrian indications were present. Furthermore, there did not appear to be significant pedestrian activity at those locations. Mr. de Camp and Ms. Mullins discussed the times of day that the different patterns were running. Mr. Wyndham indicated that the 24-hour machine counts seemed to indicate that the AM Peak pattern should operate from 6:00 AM to 9:00 AM; the Noon Peak pattern from 11:00 AM to 2:00 pM; the PM Peak pattern from 4:00 PM to 7:00 PM; the Off-Peak pattern from 9:00 AM to 11:00 AM and 2:00 PM to 4:00 PM; the Late Evening pattern (same as the Noon Peak pattern) from 7:00 PM to 10:00 PM; and the Saturday pattern from 10:00 AM to 6:00 PM. Mr. Wyndham also suggested that in Coppell, that the Off-Peak pattern operate again in the evening from 7:00 PM until 9:00 PM. Dallas County CMAQ Program Project 75 September 16, 1997 Page 3 Mr. Tramel asked that a table showing the times of day each pattern was operating be included in the Final Report. Ms. Mullins stated that she would provide Sverdrup with the final controller time sheets showing the results of the field fine-tuning. She also indicated that the times that the Saturday pattern operates may be shortened due to excessive delays to the side streets. Mr. de Camp asked if there had been a large number of side street delay complaints. Ms. Mullins stated that there had been some but not many. Mr. de Camp recalled that Mr. Hembree had said that he had received some compliments from motorists and a police officer for the good work being done on the signals along Belt Line. Discussion of Next Steps: Mr. Wyndham asked if it was appropriate for the final travel time runs to be done at this time. Mr. Patel stated that he wanted to wait a couple of weeks to make sure that all of the comments from motorists had come in. He indicated that he would call Mr. Wyndham when he was satisfied that no more fine tuning would need to be done. Mr. Tramel suggested it was time to prepare the draft report for comments and finalize the project. Next Meeting: A next meeting was not set at this time. If a final product meeting is deemed necessary, it will be arranged in the near future. These minutes are believed accurate and comPlete. Please advise the originator, Jeremy Wyndham, within 10 days if you find errors or omissions. Attachments: Sign-In Sheet Distribute to: All present Jesse Hembree Per Birdsall Brent Adams Ivan Nicodemus Karen Jones Don Cranford Moosa Saghian Mark Goode File DALLAS COUNTY · CMAQ PROGRAM PROJECT REVIEW MEETING 8 SVERDRUP CIVIL, INC. PROJECT #75 SIGN-IN SHEET SEPTEMBER 16, 1997 ~ Tony Tramel DeShazo, Tang & Assoc. (214) 748-6740 ~ Atul Patel City of Coppell (972) 304-3682 ! Per Birdsall City of Coppell (972) 304-3545 Brent O. Adams City of Coppell (972) 304-3550 ,~~ Jim Driscoll City of Irving (972) 721-2646 Kathi Mullins City of Irving (972) 721-2646 x.3387 Jesse Hembree City of Irving (972) 721-2291 Mark Goode Sverdrup Civil, Inc. (214) 696-3433 ~~my Wyndham Sverdrup Civil, Inc. (214) 696-3433 ~ Doug Bowen Sverdrup Civil, Inc. (214) 696-3433 ~ Gerry de Camp Sverdrup Civil, Inc. (702) 378-3425 Ivan Nicodemus Parsons Brinckerhoff (214) 747-6336 ext. 26 Karen Jones Parsons Brinckerhoff (214) 747-6336 ext. 25 Jim Bernier Parsons Brinckerhoff (214) 747-6336 ext. 31 James Allen ARS Engineers (214) 747-6336 ext. 30 Don Cranford Dallas County (214) 653-7151 Moosa Saghian TxDOT (214) 320-4435