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Home My WebLink AboutSDP202000052 Study Traffic Study 2018-10-12EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 E TO: COURTNEY PALUMBO FROM: BILL WUENSCH, P.E., PTOE; WEI HE ORGANIZATION: REGENTS SCHOOL DATE: OCTOBER 12, 2018 PHONE NUMBER: SENDER'S REFERENCE NUMBER: RE: TRAFFIC ASSESSMENT — REGENTS SCHOOL SITE YOUR REFERENCE NUMBER: URGENT X FOR YOUR USE PLEASE COMMENT PLEASE REPLY PLEASE RECYCLE The purpose of this memorandum is to summarize a "due diligence" level traffic assessment for the proposed Regents school site. This document is not expected to be a substitute for a fully documented traffic impact study, but instead this initial research and analysis was performed to see if there is an approach to managing traffic while awaiting the ultimate desired diverging diamond improvements. To accomplish this goal, EPR conducted an assessment of trip generation potential, and then examined traffic impacts and mitigation strategies to offset the school's traffic impacts. The following provides a brief summary of this information. Trip Generation Two methods were utilized to examine likely trip generation. These include direct calculation per the ITE Trip Generation Manual, and also a calculation based on actual expected trip making potential per known historical bus operations, car pooling, and consideration of employees with students. Trips were calculated for year 2028 with 230 students, and then also for year 2038 with 460 students. Per the ITE Trip Generation Manual, the trip generation was calculated based on the land use of private K-12 school and code of 536. Table 1 below summarizes the land use, code, units, and trips. Table 1 Trip Generation per the ITE Trip Generation Manual Unit AM AM AM PM PM PM Scenario Land Use Code Students) Weekday TOTAL IN OUT TOTAL IN OUT 2028 Private K- 230) 12 536 230 570 186 113 73 133 56 77 2038 Private K- 460) 12 536 460 1141 373 227 146 267 112 155 Per the actual expected trip making potential, the trip generation was calculated based on the historical bus operations, car pooling, and consideration of employees with students. The EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 information that the school provided shows that the current Regents School has 160 students and 22 full-time and 6 part-time employees. These 160 students are from 94 families, within which 24 families take the school bus, 49 families car pool, three families have employees of the school, and 18 families drive individually. Based on the above student information, the total current student trips are as in Table 2. Table 2 Current Total Student Trips Travel Type Take Bus Car Pool Take Employee's Vehicle Drive Individually Total Families 24 49 3 18 94 Trips 1 25 0 18 44 The result as shown in Table 2 indicates that the current 160 students have in total 44 trips and the rate is 0.275 trips/student. Applying this rate to years 2028 and 2038 results in 63 total student trips in year 2028 and 127 total student trips in year 2038. It should be noted that student trips will arrive, drop off, and leave the school in AM and arrive, pick up, and leave the school in PM. Based on the above employee information, this memo assumed a daily pattern that full-time employees and half of the part-time employees will arrive the school in AM and leave the school in the PM, which results in 25 trips total for the current employees. This memo assumed that employee student ratio will be the same in years 2028 and 2038. Table 3 summaries the estimated employees and trips in years 2028 and 2038. Table 3 Estimated Employees in the Years 2028 and 2038 Year 2018 2028 2038 Students 160 230 460 Full Time Employee 22 32 64 Part Time Employee 6 9 18 Trips 25 37 73 Per the above calculation, in year 2028, there will be 63 student trips arriving, dropping off, and leaving the school in AM and arriving, picking up, and leaving the school in PM and 37 employees arriving the school in AM and leaving the school in PM; in year 2038, there will be 127 student trips arriving, dropping off, and leaving the school in AM and arriving, picking up, and leaving the school in PM and 73 employees arriving the school in AM and leaving the school in PM. Considering school's arriving the leaving pattern, most of the trips will arrive within the school AM peak hour, but fewer trips will leave within the school PM peak hour while others will have after school activities. Examining the ITE trip generation pattern, this memo assumed all trips will arrive within the school AM peak hour and about 71.5% of the trips will leave within the EPRPc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 school PM peak hour. Table 4 summarizes the estimated trip generation for years 2028 and 2038 per the actual expected trip making potential. Table 4 Estimated Trip Generation for the Years 2028 and 2038 per the Actually Expected Trip Making Potential Scenario 2028 AM 2028 PM 2038 AM 2038 PM In/Out Inbound Outbound Inbound Outbound Inbound Outbound Inbound Outbound Student Trips 63 63 45 45 127 127 91 91 Employee Trips 37 0 0 27 73 0 0 52 Total Trips 100 63 45 72 200 127 91 143 Comparing the two methods, the one per the actual expected trip making potential is based on the Regents School and can be considered as more accurate for this analysis. The ITE Trip Generation is based on a wide variety of school types withing varying land use contexts. Thus, the analysis for Regents will use the trip generation method per the calculated (actual) expected trip making potential for the following analysis. Background Traffic The background AM and PM peak hour traffic counts at the two ramp intersections with Fontaine Avenue were taken from a recent traffic study performed by VHB for VDOT for the diverging diamond interchange. Also, growth rates from that same report were utilized for this analysis. The following figures illustrate the existing, year 2028, and year 2038 AM and PM peak hour traffic counts. Figure 1 Existing Traffic Volumes Ard 29 SB 2NB PM 29 SB 32 436 or, 315 49 298 ~ 35 J L, li4 ~ 189 4J 4 911 38 ~ 31 + #1 ro 98 lfi 443 ~ 33 935 13 7 295B 29 NB 295E EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 Figure 2 2028 No Build Traffic Volumes AM 295B 29 NB PM 29 SB 29 NB 39 531 ~ 50 L 354 60 363 ~ 37 L 629 4 r 212 230 4 r 1111 1123 Fontaine Fontaine Fontaine Fontaine 40 ~ 38 +1 r+ 103 ~ 54 #1 r+ 20 .7 540 ~ 40 1140 Ifi It 429 ~ 30 261 29 5B 29 NB 29 SB 29 NB Figure 3 2038 No Build Traffic Volumes AM 29 SB 29 NB PM 29 SB 29 NB 48 648 ~ 53 L 468 73 443 ~ 39 L 767 4.11 4 r 259 4- 281 4J 4 r 1354 4- 1369 Fontaine M Fontaine Fontaine Fontaine 42 ~ 46 + 1 r+ las ~ bs + *1 r+ 24 658 ~ 49 1389 19 123 ~ 37 318 29 SB 29 NB 29 SB 29 NB Site Trip Distribution and Assignment Trip distribution is based on consideration of trip patterns at Regents school in a previous study, and also consideration of population distribution throughout the region. The following illustrates the assumed trip distribution. It should be noted that 2% of the trips (2 trips in year 2028 and 4 trips in year 2038) were assumed from/to the local residential area along Buckingham Circle, Reservoir Road, and Foxhaven Farm Figure 4 Site Trip Distribution AM 29 SB 29 NB PM 295E 29 NB ice L ° ME a ~ L 4j 14 r 0 ~ % 41 4 r 0 4- 26% F.nt.i— Fontaine Fontaine Fontaine 13% ~ 47% + r+51% ~ 21% + r+ 25% 21% ~ 0 47% .1 2,% ~ a 295B 29 NB 295E 29 NB 0.tb..nd The site trips were assigned to the road network based on the trip generation and the distribution as noted above. The build condition site trips for both year 2028 with 230 students and year 2038 with 460 students are shown below. Figure 5 2028 Site Trips EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 AM 295E 29 NB PM 29 SB 29 NB 0 - L 0 0 - L 0 j 4 r o «j 4 r o Fo ta e Fo Ta e Fo ta,e Fo Ta e 46 ~ 30 + r 37 ~ 18 + r 16 . 16 ~ 0 34 . 19 ~ 0 29 SB 29 NB 29 SB 29 NB Figure 6 2038 Site Trips AM 295E 29 NB PM 29 SB 29 NB IIII 50 0 ~ 146 0 43 0 ~ 0 41 4 r 0 4- 52 41 4 r 0 4- F..t.i- / M F..t.i- F..I.i e o to e r 73 ~ 36 + 11 r 32 1 33 ~ 94 0 67 37 ~ 23 0 29 5B 29 NB 29 SB 29 NB Build Condition Traffic Volumes Combining the background traffic with the site trips as previously shown, the following illustrates the build condition traffic volumes. It should be noted that in build conditions only AM traffic volumes were shown, since the school traffic is very minimal in the regular PM peak hour (i.e. 4:30 to 6:OOPM). Figure 7 2028 Build Traffic Volumes AM 29SB 29 NB 64 531 ~ 123 L 384 41 4 r 212 ~ 256 o ta e F-t.ine B6 67 1 ti r 35 556 ~ 87 1140 29 SB 29 NB Figure 8 2038 Build Traffic Volumes EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 AM 29 SB 29 NB 98 fi48, ~ 199 468 J r 259 ~ 333 135 ~ , 106 , 56 fi91 ~ 143 1389 29 5B 29 NB Traffic Analysis The no build and build condition traffic was analyzed as needed to compare future build conditions with future no build conditions. The worst impacts were found to be at the southbound ramp, thus various mitigation strategies were examined including: Adding an exclusive right turn lane to the southbound ramp Adding an exclusive westbound left turn lane at the southbound ramp and an additional westbound through lane at the northbound ramp. Signalizing the southbound ramp (with no additional lanes) Signalizing the southbound ramp and adding an exclusive right turn lane to the southbound ramp, adding an exclusive westbound left turn lane at the southbound ramp and an additional westbound through lane at the northbound ramp For the signalized scenario, the future no build PM traffic volumes were analyzed with the signalized configuration to test to see if there were adverse impacts or if the signal could also work in the regular PM. The following tables summarize the traffic analysis results per the following scenarios: 1. AM Existing conditions Existing AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.3 A/2.1 C/16.3 B Approach LOS/Delay A/1.3 A/2.1 C/16.3 11.1 Movement Queue 0 51 316 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.0 A/0.9 A/0.3 A/3.3 A/9.6 A/7.4 A Approach LOS/Delay A/1.1 A/2.2 A/7.4 4.6 Movement Queue 29 0 0 48 61 0 EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 2. AM Year 2028 no build conditions Year 2028 No Build AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.5 A/2.3 E/45.4 D Approach LOS/Delay A/1.5 A/2.3 E/45.4 30.1 Movement Queue 4 57 500 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.1 A/1.0 A/0.4 A/3.6 B/11.7 A/9.5 A Approach LOS/Delay A/1.2 A/2.4 A/9.6 5.7 Movement Queue 31 0 0 72 58 0 3. AM Year 2028 build conditions (230 students) Year 2028 Build AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.7 A/2.7 F/115.7 F Approach LOS/Delay A/1.7 A/2.7 F/115.7 64.5 Movement Queue 8 73 500 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.4 A/1.0 A/0.6 A/3.9 B/13.2 A/9.5 A Approach LOS/Delay A/1.2 A/2.6 A/9.8 5.9 Movement Queue 42 0 0 F 111 76 0 4. AM Year 2028 build conditions (230 students) with an exclusive right turn lane at the southbound ramp Year 2028 Mitigation #1 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL SBR 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.8 A/2.7 F/113.6 B/12.2 F Approach LOS/Delay A/1.8 A/2.7 F/103.5 59.0 Movement Queue 9 75 500 300 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.3 A/1.0 A/0.6 A/3.9 B/13.7 A/9.5 A Approach LOS/Delay A/1.3 A/2.6 A/9.8 5.9 Movement Queue 37 0 0 125 80 0 EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 5. AM Year 2028 build conditions (230 students) with an exclusive right turn lane at the southbound ramp and an exclusive westbound left turn lane at the southbound ramp i.e. WBL and WBT versus the shared lane) and an additional westbound through lane at the northbound ramp Year 2028 Mitigation #2 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL WBT SBL SBR 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.9 A/2.9 A/0.5 F/79.4 D/31.0 F Approach LOS/Delay A/1.9 A/2.0 F/74.5 43.4 Movement Queue 1 67 0 500 300 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.3 A/1.0 A/0.8 A/4.2 B/14.8 A/9.6 A Approach LOS/Delay A/1.3 A/2.9 A/9.9 6.0 Movement Queue 40 4 2 151 85 0 6. AM Year 2028 build conditions (230 students) with traffic signal at southbound ramp intersection Year 2028 Mitigation #3 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/8.0 C/15.4 B/15.0 B Approach LOS/Delay A/8.0 C/15.4 B/15.0 14.3 Movement Queue 87 208 340 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.6 A/1.2 A/0.6 A/4.0 B/14.5 A/9.5 A Approach LOS/Delay A/1.5 A/2.6 A/9.9 5.9 Movement Queue 42 0 0 F 163 89 0 7. AM Year 2038 no build conditions Year 2038 No Build AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.5 A/2.5 F/115.1 F Approach LOS/Delay A/1.5 A/2.5 F/115.1 59.1 Movement Queue 0 64 500 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.5 A/1.0 A/0.5 A/4.3 B/15.0 B/12.5 A Approach LOS/Delay A/1.2 A/2.9 B/12.6 7.5 Movement Queue 38 0 0 129 64 0 EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 8. AM Year 2038 build conditions (460 students) Year 2038 Build AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.8 A/3.5 F/175.7 F Approach LOS/Delay A/1.8 A/3.5 F/175.7 69.7 Movement Queue 13 102 500 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.6 A/0.9 A/0.8 A/4.8 C/17.6 13/13.0 A Approach LOS/Delay A/1.3 A/3.1 B/13.4 8.3 Movement Queue 42 0 6 200 110 0 9. AM Year 2038 build conditions (460 students) with an exclusive right turn lane at the southbound ramp Year 2038 Mitigation #1 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL SBR 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.8 A/2.7 F/189.3 C/18.8 F Approach LOS/Delay A/1.8 A/3.5 F/167.4 68.9 Movement Queue 11 108 500 300 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.8 A/0.9 A/0.8 A/4.8 C/17.8 B/13.1 A Approach LOS/Delay A/1.3 A/3.1 B/13.5 8.4 Movement Queue 48 0 6 165 114 0 10. AM Year 2038 build conditions (460 students) with an exclusive right turn lane at the southbound ramp and an exclusive westbound left turn lane at the southbound ramp i.e. WBL and WBT versus the shared lane) and an additional westbound through lane at the northbound ramp Year 2038 Mitigation #2 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL WBT SBL SBR 1. Rte 29/Fontaine SB Movement LOS/Delay A/1.9 A/3.5 A/0.6 F/156.7 F/72.5 F Approach LOS/Delay A/1.9 A/2.2 F/145.4 63.7 Movement Queue 6 79 6 500 300 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/3.7 A/1.0 A/1.2 A/5.4 C/18.2 B/13.0 A Approach LOS/Delay A/1.3 A/3.6 B/13.5 8.4 Movement Queue 47 2 0 190 110 0 EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 11. AM Year 2038 build conditions (460 students) with traffic signal at southbound ramp intersection Year 2038 Mitigation #3 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay B/10.8 D/33.3 F/51.2 E Approach LOS/Delay B/10.8 D/33.3 F/51.2 39.6 Movement Queue 128 405 500 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/4.7 A/1.6 A/1.0 A/6.2 D/27.9 B/13.1 A Approach LOS/Delay A/2.0 A/4.0 B/14.5 8.6 Movement Queue 67 0 6 263 147 0 12. AM Year 2038 build conditions (460 students) with traffic signal at southbound ramp intersection and with an exclusive right turn lane at the southbound ramp, an exclusive westbound left turn lane at the southbound ramp (i.e. WBL and WBT versus the shared lane) and an additional westbound through lane at the northbound ramp Year 2038 Mitigation #4 AM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL WBT SBL SBR 1. Rte 29/Fontaine SB Movement LOS/Delay C/19.8 C/19.5 B/12.2 C/18.1 A/6.1 C Approach LOS/Delay C/19.8 C/16.1 C/16.5 16.8 Movement Queue 149 195 149 402 255 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/4.4 A/1.6 A/1.2 A/6.2 D/25.1 B/12.8 A Approach LOS/Delay A/2.0 A/4.1 B/14.0 8.4 Movement Queue 59 0 34 234 141 0 EPRpc EPR, PAC. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 13. PM Year 2028 build conditions (230 students) with traffic signal at southbound ramp intersection. No school traffic was added and PM Year 2028 no build condition traffic volumes were used since the school traffic is very minimal in the PM peak hour (i.e. 4:30 to 6:OOPM). This analysis is just to see if there were adverse impacts or if the signal could also work in the background PM peak hour. Year 2028 Build PM Movement/Approach Fontaine EB Fontaine WB Rte 29 SB Overall EBT/R WBL/T SBL/R 1. Rte 29/Fontaine SB Movement LOS/Delay A/6.4 E/47.6 F/181.7 F Approach LOS/Delay A/6.4 E/47.6 F/181.7 78.0 Movement Queue 80 500 500 Movement/Approach Fontaine EB Fontaine WB Rte 29 NB Overall EBL EBT WBT WBR NBL NBR 2. Rte 29/Fontaine NB Movement LOS/Delay A/6.9 A/1.3 F/88.7 D/25.1 F/652.5 A/5.8 F Approach LOS/Delay A/2.0 F/65.9 F/70.8 54.7 Movement Queue 52 0 1000 1000 262 207 Findings 1. The additional lanes by themselves do not get the LOS/delay/queuing back down to a level equaling the no build conditions 2. In year 2028, the traffic signal at the southbound ramp does work well in the morning as a mitigation measure. However, it does not work in the PM peak hour traffic due to the very high left turn volume accessing the southbound on -ramp. 3. In year 2038, the traffic signal at the southbound ramp does get the LOS/delay/queuing back down to a level equaling the no build conditions in the morning; however, in order to get the traffic working well in the morning, the mitigation measure should include the traffic signal at southbound ramp intersection with an exclusive right turn lane at the southbound ramp, and an exclusive westbound left turn lane at the southbound ramp (i.e. WBL and WBT versus the shared lane) and an additional westbound through lane at the northbound ramp. The same as in year 2028, it does not work in the PM peak hour traffic due to the very high left turn volume accessing the southbound on -ramp. 4. If the signal were to be operated as an actuated signal in the AM peak hour, and then put into flash mode for the PM peak hour, traffic conditions could be manageable in year 2028, although this traffic signal scheme is not typically used. 5. In year 2038, the signal should be combined with an exclusive right turn lane at the southbound ramp and an exclusive westbound left turn lane at the southbound ramp (i.e. WBL and WBT versus the shared lane) and an additional westbound through lane at the northbound ramp to maintain the traffic conditions manageable. Note that this only works for the AM peak hour and the PM peak hour would need to be in flash operation. EPRpc EPR, P,C. "ENGINEERING & PLANNING RESOURCES" 902 E JEFFERSON ST. UNIT 101, CHARLOTTESVILLE, VA 22902 The FHWA MUTCD notes: Section 4D.28 Flashing Operation of Traffic Control Signals — General Standard: 01 The light source of a flashing signal indication shall be flashed continuously at a rate of not less than 50 or more than 60 times per minute. 02 The displayed period of each flash shall be a minimum of 112 and a maximum of 213 of the total flash cycle. 03 Flashing signal indications shall comply with the requirements of other Sections of this Manual regarding visibility -limiting or positioning of conflicting signal indications, except that flashing yellow signal indications for through traffic shall not be required to be visibility -limited or positioned to minimize visual conflict for road users in separately controlled turn lanes. 04 Each traffic control signal shall be provided with an independent flasher mechanism that operates in compliance with this Section. 05 The flashing operation shall not be terminated by removal or turn off of the controller unit or of the conflict monitor (malfunction management unit) or both. 06 A manual switch, a conflict monitor (malfunction management unit) circuit, and, if appropriate, automatic means shall be provided to initiate the flashing mode. Option: 07 Based on engineering study or engineering judgment, traffic control signals may be operated in the flashing mode on a scheduled basis during one or more periods of the day rather than operated continuously in the steady (stop -and -go) mode. Going forward, the concept of a temporary traffic signal installation (while awaiting the full interchange improvements if funded) operating in stop-go mode in the AM peak hour and flashing operation all other hours of the day for year 2028. Looking out to year 2038 would require the signal combined with an exclusive right turn lane at the southbound ramp and an exclusive westbound left turn lane at the southbound ramp i.e. WBL and WBT versus the shared lane) and an additional westbound through lane at the northbound ramp. Depending on the outcome of that coordination, full traffic impact study documentation can be prepared. CC: Ashley Davies —Williams Mullen Valerie Long —Williams Mullen Justin Shimp — Shimp Engineering