Item 7 - Traffic Circulation Memo
kimley-horn.com 801 Cherry Street, Unit 11 Suite 950, Fort Worth, TX 76102 817-335-6511
MEMORANDUM
To: John D. Blacker, P.E.
Hart, Gaugler, & Associates, Inc.
From: Jeffrey Whitacre, P.E., AICP, PTP
Kimley-Horn and Associates, Inc.
Date: August 6, 2019
Re: Rockenbaugh Elementary School Circulation Study
Southlake, Texas
PURPOSE
The purpose of this study was to evaluate alternatives to Rockenbaugh Elementary School’s drop-off and
pick-up vehicle circulation plan. The school will be building an additional structure on the eastern side of
the campus to increase the Pre-K class size. In addition, multiple other adjustments to the school’s access
points are being considered. Additional goals for the new circulation plan include:
⚫ Increasing overall queue lengths to avoid back up along Byron Nelson Pkwy,
⚫ Redirecting Pre-K circulation to new building location, and
⚫ Separating the school buses from the drop-off vehicles.
PROPOSED CIRCULATION ALTERNATIVES
Using a school vehicle queue length formula, three circulation alternatives were evaluated to accommodate
the proposed changes and increased capacity for the school. From these three options, a preferred
alternative was created as a hybrid of these plans:
⚫ Option 1 assumes that the southmost driveway along Byron Nelson Pkwy is closed and a new
driveway is built along Zena Rucker Rd.
◼ The K-4 circulation path begins at the northern entrance along Byron Nelson Pkwy,
continues down the western side of the campus, and drops off at the circle drive on
the southern corner
◼ The Pre-K queue begins at the new driveway along Zena Rucker Rd, snakes through
the existing parking lot, and drops off down where the new Pre-K addition will be
located
◼ Bus route enters at the same driveway as K-4 but drops off along the north entrance
of the school. Install a remote access gate to separate the K-4 and Pre-K queues
from each other, while allowing the school buses to cross through
⚫ Option 2 keeps the same assumptions as Option 1, with the addition of a new dri veway that
continues the alignment of Parkwood Dr.
◼ K-4 circulation route would enter and exit from new access point at Parkwood Dr,
keeping the same alignment as Option 1 the rest of the way
08-07-19
kimley-horn.com 801 Cherry Street, Unit 11 Suite 950, Fort Worth, TX 76102 817-335-6511
◼ Pre-K and bus routes would also remain the same, with the location of the remote
access gate moving slightly to fully close off access from the northmost driveway on
Byron Nelson Pkwy
⚫ Option 3 assumes that the southern driveway along Byron Nelson Pkwy is expanded to allow for
two lanes in and one lane out
◼ K-4 route will enter and exit from expanded driveway
◼ Pre-K route will use the northern Byron Nelson driveway to enter and exit
◼ K-4 and Pre-K drop off locations are the same as the previous options
◼ Buses will enter on the south end, drop off at the front, and then exit on the north side
OPTION 4 - PREFERRED ALTERNATIV E
The fourth, and preferred, circulation option is a hybrid of the previous configurations. It assumes the
addition of the mid-median driveway from Option 2, and the widening of the southern driveway along
Byron Nelson.
The Pre-K route follow the same path as it does in Option 3. Buses will take the southbound left turn into
the new mid-median driveway, enter through a remote access gate, and drop off at the front of the school.
To accommodate this left turning traffic, a turn pocket should be installed in the median.
The K-4 circulation route is the most different in Option 4. In this plan, a two-lane circulation pattern is
maintained throughout the whole drop-off line. Both lanes enter through the widened southern driveway
on Byron Nelson, continue around the circle drive, and drop off in two lanes. To exit, cars must merge into
one line after they drop-off and will exit out the same driveway they entered from.
Other improvements along this route include: a speed table along this path, a double-load crosswalk, and
a canopy covering at the drop-off waiting area. The full circulation plan for Option 4 is shown in Exhibit 1.
QUEUE LENGTH ANALYSI S
Once these new circulation routes were established, the queue lengths were measured and evaluated
against a formula. This formula uses the total enrollment of a school to determine how many trips will be
produced in the AM and PM periods. These trips are then converted into an average and high demand
queue length by assuming a car length of 20 feet. The table below shows the results from this calculation,
as well as the estimated queue length for the preferred alternative.
Calculated Queue Lengths Preferred Alternative
Average High Demand Maximum K-4 Queue Length
1,110 ft 1,440 ft 1,880 ft 1,780 ft
If you have any questions, please contact me at jeff.whitacre@kimley-horn.com or by phone at
817-339-2254.
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Rockenbaugh Elementary School
Southlake, TXEx 1. Preferred Circulation Option
0 150 30075Feet´
Notes
Expand driveway on Byron Nelson to
accomodate second lane and right turn radius
Add speed table
Reconfigure K-4 drop off area:
- Maintain 2 travel lanes in
- Install new median
- Add double-load crosswalk
- Build canopy covering over waiting area
- Pave new exit lane for merging
Install turn pocket along Byron Nelson
Add new bus entrance only driveway
Add gate to prevent cut-through traffic
Proposed addition
Proposed parking lot
Possible future driveway along Zena Rucker
1.
2.3.
4.5.6.7.8.9.
Circulation Routes
K-4
Pre-K
Bus
1,780 ft
870 ft
470 ft
Pre-K:
7:40 - 8:00 AM Drop-Off
1:55 PM Pick-Up
K-4:
7:30 - 8:00 AM Drop-Off
2:55 PM Pick-Up