Item 6B TNP N White Chapel Traffic Study 4-23-11No TFAGUE NULL AND PERKINS
Civil Engineering Surveying Landscape Architecture Planning
Memorandum
To: Gordon Mayer, P.E.
From: Robert Jenkins, P.E.
cc:
Date: April 23, 2010
Re: SLK09292 - White Chapel Design Study
Introduction
�s 1�
9*
s61
a � TA
t?`. a aoa aaq vara eaea a�
PORDE, J��Ieo • NS
dte •aaaaa•aaoaasaaaa�o-t
�1 40016 e
Traffic engineering services have been provided to support design decisions for
widening White Chapel Boulevard. These involved collecting traffic data; projecting
traffic growth; and evaluating capacity and control needs at the key intersections with
Highland Street, North Access Drive to the High School/Ascot Drive, South Access Drive
to the High School, and Chapel Downs Drive. The intersection at Highland Street was
evaluated for traffic signal and roundabout operations.
Data Collection and Projection
Turning movement counts were collected at the four intersections identified above.
Twenty-four hour counts were collected on White Chapel approaches/departures to and
from Highland and on Highland approaches. The 24 hour counts at Highland were
grown at 6% to establish volumes in 2012, and these were used to evaluate signal
warrants for the widened intersection. Figure 1 shows the existing a.m. peak and
p.m. school peak turning movement counts..
Future traffic volumes (2019) were estimated by growing background traffic and
estimating school trips at capacity. Special consideration was taken while growing
these counts. New student drivers during the spring semester were taken into account;
school trip growth was stopped after the school reached maximum capacity; and
background trips were grown at a rate of 6%. Existing patterns and a series of
extensive spreadsheets were used as the basis for distributing school trips. Figure 2
shows the projected 2019 a.m. peak and p.m. school peak turning movement counts
with White Chapel reconstructed to four lanes divided.
Existing Conditions and Observations
White Chapel Blvd. currently serves as a two lane undivided roadway with left turn bays
at all study intersections. South of Chapel Downs Drive and north of Ascot Drive,
school zone flashing beacons reduce the travel speed from 40 MPH to 20 MPH during
school peak hours. The current traffic control devices allow traffic to flow continuously
from FM 1709 to Highland Street.
1100 Macon Street Fort Worth, Texas 76102 817.336.5773 phone 1817.336.2813 fax
Item 613 TNP N White Chapel Traffic Study www.tnp-online.com
Figure 1 - White Chapel Blvd.
2009 Peak Hour Volumes
CMDM(0
R4(2)
-14(7)
Legend
1
f,
ornm
C7
M i
°
�S n
163 (148)
3 (7)
�•a'Y,�' _ _"� ' '
209(267)-4
V
4 N O'
d South Access Drive i
I
37(42)-0
282(239)-A
a
m°n R
W N
{(fl f+
� N
16(11)-
2
6(11)x2 (2)-
33 (49)-'*
Mm TEAGUE NALL AND PERKINS
Item 613 TNI `f '� gife d6 pe,"T�"Wic* Judy'
I
91
.rTr
E Highland St AL
r23 (17)
o �- � E:'C6ape a4v 9 Or
u)o2
v
M
ti
Figure 2 - White Chapel Blvd. 2014
Peak Hour Volumes
..�t
Legend
� AM (PM) Volumes
R7 (4)
i k
-t-25(13)
32 (g) E Highland St
124 (93)it
107 (97) -►
r
~6(2)
e
r 11 (13)
r
r i T
- � rr,, t * 'T f ,�, � 17'6 (155).x►
fOV:
�`', 1 e 1 _ 225 (279) Y m y
•� y�`� — 6� � I • 1 N tf7
ar✓� ' �� _. 4 i n 'd
m
C13
l." South Access Drive ►t
' —0
M-= TEAGUE NALL AND PERKINS
Item 613 TNP N''1% Mf9 dfii peft affiic iu
R 22 (16)
t 0 (0)
Ar 41 (30) ;1
R ?
o n ""Chapel DeAr
S LO
LO M
Ca
The Highland intersection currently exists as an all way stop operation and meets
multiple traffic signal warrants as an intersection of two lane roadways. Installing a
traffic signal can create longer gaps in thru traffic which will benefit east -west
movements at intersections to the south. The east -west movements at the school
Access Drives currently function at congested levels of service.
The southbound traffic passing through the North Access Drive of the School
intersection can benefit from the addition of a right turn bay. In addition, restriping the
eastbound approach to a left and thru along with a right only lane will also improve the
functionality of this intersection.
Operations Analysis
Synchro 7 and SimTraffic software were used to model the intersection operations
between Highland Street and Chapel Downs Drive. SIDRA INTERSECTION 4 software
was used to evaluate the operation of a roundabout at the Highland Intersection.
Future Roadway Improvements
The study took into account the widening of White Chapel Blvd to a four lane divided
roadway with left turn bays and the previously mentioned improvements like those at
the North Access Drive/Ascot Drive. A signal warrants check of the Highland
intersection in 2012, when the new 4 lane facility is in place, suggests that Warrants 2,
3, and 8 will be met.
Recognizing that Traffic at the Highland intersection will ultimately experience
undesirable delays under an all -way stop operation, it is appropriate to either signalize
or reconfigure the intersection to meet traffic growth. Constructing a roundabout for
this intersection appears to be a legitimate choice. A roundabout with two-lane
approaches on White Chapel and single lane approaches on Highland was analyzed with
SIDRA for the projected 2012 and 2019 a.m. peaks. Table 1 compares effectiveness
of a signal operation, a roundabout (described above) and a roundabout with an
eastbound right turn by-pass. It demonstrates that the single lane, eastbound
approach to the roundabout will experience congestion by 2019. However, the addition
of an eastbound right turn by-pass lane will eliminate the problem. The traffic signal
will handle the 2019 projections but not as efficiently as the roundabout with an
eastbound right turn by-pass. This roundabout is attached with an alternative
configuration.
The School's North Access Drive/Ascot Drive intersection will function at an undesirable
level of service due to background traffic growth on White Chapel and traffic generated
by the fully enrolled Carroll High. A traffic signal with the above improvements is
recommended.
The School's South Access Drive intersection will experience a heavy northbound left
turn movement which requires ample storage; a 4 lane roadway section with a reverse
Left Turn Lane median configuration is recommended between this intersection and
Chapel Downs Drive.
Page 4
Item 613 TNP N White Chapel Traffic Study
At the Chapel Downs Drive intersection, the east -west volumes are relatively low; these
movements will benefit from gaps generated by the traffic signal at the North Access
Drive/Ascot Drive intersection, therefore the existing two way stop sign operation can
remain.
Table 1 - Comparison of Signal and Roundabout for Highland Intersection
This provides you with a brief overview of what we think can be expected and what
some of your options are.
Page 5
Item 6B TNP N White Chapel Traffic Study
Movement LOS / Approach
Intersection
Control
Confi uration
Eastbound
Lefts Thrus Ri hts
Southbound
Lefts Thrus Ri hts
westbound
Lefts Thrus Ri hts
Northbound
Lefts Thrus Ri hts
2012 AM Peak
LOS
Avg Delay (sec)
95% Queue (ft)
2019 AM Peak
LOS
C
C
A
A
B
C
C
A
A
B
Avg Delay (sec)
32.5
34
8.9
7.2
11.6 1
22.6
25.4
5.9
5.4
12.3
95% Queue (ft)
82
85
28 1
9
186 1
29
31
16
67
2012 AM Peak
LOS
B
A
A
B
A A
B
AA
B
A
A
A
AvgDela sec
14.2
7.8
9
13
5.9 7.2
11.5
5.1
6.2
13,6
6,4
7.7
7.6
95% Queue(ft)
926
120
120
48
48 48
12
12
12
56
56
56
2019 AM Peak
LOS
D
D
D
B
A A
B
A
A
B
A
A
B
Avg Dela sec
44.8
38.4
39.5
13.5
6.3 7.6
12.9
6.4
7.6
14.6
7.3
8.6
16.1
95% Queue (fl:11
573
1 573
1 573 1
72
72 1 72 1
23
1 23
1 23 1
100
1 103 1
103
2019 AM Peak
LOS
B
I A
A
8
A A
B
A
A
B
A
A
A
Avg Dela sec
11.9
5.5
6
13.5
6.3 7.6
12.9
6.5
7.6
14.6
7.3
8.6
7.6
95% Queue ft
66
66
60
12
72 72
23
23
23
73
95
95
This provides you with a brief overview of what we think can be expected and what
some of your options are.
Page 5
Item 6B TNP N White Chapel Traffic Study
r
4
OWA
* � �`. � s` -: ,� �•` ,� ` � --- -cam\�—
SCALE 1 " — 80'
ILJIL
Z
door- - - - - - - _
1It
�4
.. CN `y,.. _. _ -._ -•._ ,... ,. . �.., . :.. .. .. t, ....... N-: Js*•n � ..Jy.,,y. ! -N .! - J !- Jt}. f J W, y-+.
oim. y.-.,..:. •.y.4•:ti 4:•:.; wy ..; ...;
*..
v._. . r...v ...a. ... ..-. ._... .�. ..... .. • , ... Y ,. ...4+: Y,t s......- ,....n.t-Y. .. . .+. aR .\"T R..�.. •v:... ��,.,
... -. ... .. n ... .. - .:_. ..a. ....R .... ..V .. ., .. .. .•,•.. ... v ....t:,nv t -. .14h..y.. til y. t}.,t. Y- Y.
.. - -, .. ..... ...� .. ... .. .. ....� ... ., ....v.., v.t .. Ai4y nt tvnv 4 53 ...1•..
4.k l
-. � ...... ... .... .ti .. .. ., .. . . . ..... •....,...,,-: ....... .....Y••:•..v,•.,•. -, v,. .:. - .. ...iv.'ti;:.44:}'%l: tiSY,•J,....
.. .......... ... _ : _... ... .�. _ ,... w....................... � CHAPEL BLV
R 4i
- `-
No
Mr
y,1
414
s •t'4
1k 4k
-
.,, __ • ALTERNATE
�'• ROUNDABOUT CONCEPT
4i
k f +N DRAWING
WHITE CHAPEL BLVD / HIGHLAND ST
' SOUTHLAKA TEXAS
t7EA= IMUAMPEA
,��, , ' -_ ' `• !NC_ r•rlr Worrt*. Tisii •fifoi
Item 6B TNP N White Chapel Traffic Study; �► r....:arar•a••ur•.rs:r•rn•a�-iar•