Item 10 & 11 - Lee Traffic Letter
ARIZONA
TEXAS
NEW MEXICO
OKLAHOMA
3030 LBJ Freeway, Suite 1660, Dallas, TX 75234
(972) 248-3006 office (972) 248-3855 fax | www.leeengineering.com Page 1 of 3
October 28, 2021
Mr. Aaron Bidne
Granite Properties
5601 Granite Parkway, Suite 1200
Plano, TX 75024
Re: Trip Generation Characteristics for Southlake Town Square Block 16
Dear Mr. Bidne:
Lee Engineering has analyzed the trip generation characteristics of the proposed development to be
located on Block 16 in Southlake Town Square in Southlake, Texas. The current development
proposal includes a total of 305,000 SF of office space and 22,000 SF of restaurant space.
The number of trips generated by a development is a function of the type and quantity of the land
use of the development. The number of vehicle trips generated by the proposed development was
estimated based on trip generation information provided in the publication entitled Trip Generation
Manual, 10th Edition, by the Institute of Transportation Engineers (ITE). The trip generation rates
for the proposed development and the entering/exiting splits for traffic generated by the
development are shown in Table 1. This table also presents the estimated number of trips
generated by the proposed development. As shown in Table 1, the proposed development is
predicted to generate 4,974 trips on a daily basis with 329 trips during the AM peak hour and 500
trips during the PM peak hour.
Lee Engineering completed a traffic study for Block 16 in 2015. The proposed development in 2015
included 340,300 SF of office space and 27,000 SF of restaurant space. One 154,000 SF office
building with supporting parking garage from that proposal has been built. Trip generation
estimates that were used in that study are presented in Table 2. These calculations were done using
a prior edition of the Trip Generation Manual. As can be seen, the daily and peak hour trip
generation estimates are lower for the currently proposed development and thus the impacts of the
development on area traffic should be less than identified in the 2015 study.
Page 2 of 3
Table 1: Trip Generation – Proposed Block 16 Development 2021
Land Use ITE
Code
Variable
(X) Average Weekday AM Peak Hour PM Peak Hour
Equation/Rates1
General
Office 710 1000 Sq
Ft GFA
Ln(T) = 0.97Ln(X) +
2.5
T = 0.94(X) +
26.49
Ln(T) = 0.95Ln(X) +
0.36
Quality
Restaurant 931 1000 Sq
Ft GFA T = 83.84(X) T = 0.73(X) T = 7.8(X)
Directional Splits2
General
Office 710 1000 Sq
Ft GFA 50/50 86/14 16/84
Quality
Restaurant 931 1000 Sq
Ft GFA 50/50 50/503 67/33
Trips Generated
Land Use Amount Variable
(X) Total Enter Exit Total Enter Exit Total Enter Exit
General
Office 305 1000 Sq
Ft GFA 3,130 1,565 1,565 313 269 44 328 52 276
Quality
Restaurant 22 1000 Sq
Ft GFA 1,844 922 922 16 8 8 172 115 57
Total Trips 4,974 2,487 2,487 329 277 52 500 167 333
1 T= Trip Ends; X = 1,000 Square Feet
2 XX/YY = % entering vehicles / % exiting vehicles.
3 This number was assumed as no data was available.
Page 3 of 3
Table 2: Trip Generation – Proposed Block 16 Development 2015
Land Use ITE
Code
Variable
(X) Average Weekday AM Peak Hour PM Peak Hour
Equation/Rates1
General
Office 710 1000 Sq Ft
GFA T = 11.03(X) T = 1.56 (X) T = 1.49(X)
Quality
Restaurant 931 1000 Sq Ft
GFA T = 89.95(X) T = 0.81(X) T = 7.49(X)
Directional Splits2
General
Office 710 1000 Sq Ft
GFA 50/50 88/12 17/83
Quality
Restaurant 931 1000 Sq Ft
GFA 50/50 50/503 67/33
Trips Generated
Land Use Amount Variable
(X) Total Enter Exit Total Enter Exit Total Enter Exit
General
Office 340.3 1000 Sq Ft
GFA 3,754 1,877 1,877 531 467 64 507 86 421
Quality
Restaurant 27 1000 Sq Ft
GFA 2,428 1,214 1,214 22 11 11 202 135 67
Total Trips 6,182 3,091 3,091 553 478 75 709 221 488
1 T= Trip Ends; X = 1,000 Square Feet
2 XX/YY = % entering vehicles / % exiting vehicles.
3 This number was assumed as no data was available.
Please let me know if you need any additional information on this matter.
Sincerely,
Joseph T. Short, P.E., PTOE
President