HomeMy WebLinkAboutPLATT PROPERTY PUD PRELIMINARY - 3 90B - SUBMITTAL DOCUMENTS - ROUND 1 - TRAFFIC STUDYM
MEMORANDUM
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To: Chuck Betters, B & P Partnership
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Linda Hopkins, The Group Inc.
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Rita Davis, Transportation Planner
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From: Matt Delich
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Date: May 31, 1991
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Subject: Traffic analysis of the development of the Platt
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Property (File 9125)
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This memorandum addresses the operation at the
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Shields/Wakerobin stop sign controlled intersection in Port
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Collins. It has been proposed that approximately 115 dwelling
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units be developed on the Platt Property. The Platt Property
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is located east of Seneca Street and north of Wakerobin and
Regency. There is currently no development on the Platt
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Property. Initial access to the Platt Property will be via
Wakerobin and Regency. Primary access will be via Wakerobin.
This traffic study analyzes how many dwelling units can be
developed and still maintain acceptable operation at the
Shields/Wakerobin intersection. The hours analyzed were the
peak hours of the street (Shields) which also are the peak
hours of the proposed residential use.
Peak hour traffic counts were obtained at the Shields/
Wakerobin intersection on May 21, 1991, as shown in Figure 1.
Raw data is provided in Appendix A. There is an existing
residential subdivision accessing the east leg of this
intersection. There is some vacant land north of Harmony Road
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between Shields Street and Starflower Drive. Traffic to/from
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this leg will increase when this vacant land is developed, but
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this is not likely to occur within the analysis period. Table
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1 shows the peak hour operation at the Shields/Wakerobin
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intersection. Calculation forms are provided in Appendix B.
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Based upon the 1985 Highway Capacity Manual technique for stop
sign controlled intersections, the intersection operates
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acceptably, except for eastbound and westbound left -turn exits
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from Wakerobin Lane. These are in the level of service E
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By definition, acceptable operation is considered
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cccategory.
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to be level of service D or better. Based upon recent
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research, it was found that the 1985 HCM capacity technique
for stop sign controlled intersections gives an overstatement
of the level of service. The expected delay to the eastbound
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left turns would be 21-31 seconds per approach vehicle in the
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morning peak and 20-30 seconds per approach vehicle in the
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afternoon peak. By other criteria in the 1.985. HCM, the level
of service of these left turns is more appropriately defined
as level of service D. I have attached a copy of two research
papers discussing this subject in Appendix C. Much of the
NIATTHEW J. DELICH, P.E.
3413 BANYAN AVENUE
LOVELAND, CO 80538
TABULAR SUMMARY OF VEHICLE COUNTS
Observer DateMAY f /49l pay T,_)" NAq City FnP-' Catc- I wJ s R = Right turn
S = Straight
INTERSECTION OF Sf� I.� L i 7 S: AND IA)AKO EC, R 1 /U L = Lett turn
TIME
BEGINS
SI�IELDs
SFF fL Lz
TOTAL Northtrom
South '
QAKr= i 0E-1,A)
LJAKGK0(31AJ
TOTAL
East
West
TOTAL
ALL
tram NORTH
tram SOUTii'
EAST
from WEST
'I
R
S
L
Total I
R i S I L I Total
R
I S I L
I Total II
R
I S
I L I Total
-71-�f- 114-3110s
21
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14o I I q4 11249
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SI•IIfcLDS SOUTI-1 of
W(ih::ER0B I1\1
NOF;TH BOUND
HOUR
----
QUARTER
HOLE:
---
HOUR
EACH * REPRESENTS 2' VEHICLE'S
OF
DAY
1 +=
2nd
3rd
4th
TOTAL.
A DASH MEANS HOUR VOLUME <; .17..
12
All
6
6
6
5
C'
?�
1
AM
10
5
5
9
C'c)'
_
Arl
1
4
-
4
1
f
4
A M
C
0
7
1.2
5
`aM
3
12
21
14
5()
!�
6
Al
26
41
51
66
1.81.
A.
55
1. 16
176
167
`,.' 1 '4
31
AM
1f*,):!.
101.
1. e
1.29
4`..'i9
ua.�u.n.?,..n.M.+: c.c.K..n.n..c.3.nx�•
r
AM
77
66
: 1
107
3".21
f.n.n.%.....v.<.K. .. .Fu
10
'AM
E:8
74
1OZ
88
71:
y- �f%..,.X..u.y..k
:41
AI`1
8
88
89
117
_
12
FIM
100
10,7
t_7
'S
F.
c
2
80
299,
F'M
77
119
128
102
/.I•:_6
PM
99
1'17
115
15(-,
4&.)
4
PM
109
149
162
16o
579
5
PM
174
158
164
135
6.31
6
PM
146
1 1 1
1 C5
161
54
7
P11
92
80
69
77
318
n.?f.c,w, -*lL 1. 41. .w.n
8
PM
70
77
52
67
266
9
PM
58
75
62
60
255
10
PM
41
38
35
37
151
1<?�.� n•.� ?f•n•
11
PM
35
29
14
16
94*
TOTAL VOLUME IS 61741 VEHICLES.
PEAT'.. HOURS:
MORNING PEAk" HOUR VOLUME OF 560 BEGINS AT 7:15 AM ( 8 %)
EVENING F'EAk: HOUR VOLUME OF 656 BEGINS AT 4: 45 PM ( 10
1 )
DATA COLLECTION BEGAN AT 12 AM ON WEDNESDAY, APRIL 10, 1991.
SHIELDS NORTH of
WAKEROBIN
SOUTH BOUND
HOUR
~~--
QUARTER
HOUR
HOUR
EACH * REPRESENTS 23 VEHICLES
OF
DAY
1st
2nd
3rd
4th
TOTAL
A DASH MEANS HOUR VOLU ME < 12
12
AM
7
12
2
4
25
*
1
AM
4
6
10
5
25
*
2
4M
1
2
3
0
6
�
3
AM
3
3
3
1
10
~
4
AM
2
3
13
12
30
*
5
AM
16
11
24
37
Be
****
6
AM
45
58
84
101
288
7
AM
96
148
211
160
615
8
AM
127
95
108
157
487
9
AM
87
77
88
96
348
10
AM
75
95
94
86
350
************* lib *
11
AM
95
E4
85
90
354
***************
12
PM
93
92
113
82
380
1
PM
101
77
93
84
355
*********���*�*
2
PM
97
118
101
98
4 C 6
3
PM
95
156
148
144
543
4
PM
128
111
114
163
516
**********************
5
PM
131
170
145
125
571
*************************
6
PM
142
108
129
114
493
7
PM
81
58
57
50
246
11*****
8
PM
54
56
66
63
239
9
PM
67
51
42
33
193
10
PM
30
17
22
19
Be
***�
11
PM
16
16
9
5
46
**
TOTAL VOLUME IS 6,7o2 VEHICLES.
PEAK HOURS:
MORNING PEAK HOUR VOLUME OF 646 BEGINS AT 7:15 AM ( 10 �)
EVENING PEAK HOUR VOLUME OF 609 BEGINS AT 4:45 PM ( 9 2)
DATA COLLECTION BEGAN AT 12 AM ON WEDNESDAY, APRIL 10, 1991°
WAKEROBIN WEST of
SHIELDS
EAST BOUND
HOUR
OF DAY
12 AM
1 AM
2 AM
3 AM
4 AM
5 AM
6 AM
7 A�
8 AM
9 A�
10 AM
11 AM
12 PM
1 PM
2 PM
3 PM
4 PM
5 PM
6 PM
7 PM
8 PM
9 PM
10 PM
11 PM
QUARTER HOUR
1st
2nd
3rd
4th
1
1
0
0
1
0
0
0
0
1
0
S
0
0
0
0
0
0
0
0
1
0
1
0
3
2
2
1
6
12
40
19
3
6
15
29
1�
4
5
8
6
4
4
7
9
22
40
34
13
8
5
6
5
6
10
5
3
4
38
9
13
25
20
17
18
21
33
19
13
12
10
6
8
22
29
13
7
8
4
1
57
24
1
1
1
1
1
0
O
0
1
0
0
0
O
0
TOTAL VOLUME IS 795 VEHICLES.
HOUR
TOTAL
2
1
1
0
0
2
8
77
53
27
21
105
32
26
54
75
91
41
72
20
83
EACH * REPRESENTS 4 VEHICLES
A DASH MEANS HOUR VOLUME < 2
PEAK HOURS:
MORNING PEAK HOUR VOLUME OF 105 BEGINS AT 11:00 AM ( 13 %)
EVENING PEAK HOUR VOLUME OF 91 BEGINS AT 4:00 PM ( 11
DATA COLLECTION BEGAN AT 12 AM ON WEDNESDAY, APRIL 10, 1991°
WAKERoeIM EAST of
` . I DS
WE! sT BOUND
HOUR
- -
QUARTER
HOUR
HOUR
OF DAY
Ist
2nj
=rd
4th
TOTS
12 AM
0
0
0
!
!
1 AM
0
0
!
0
!
2 AM
o
0
0
0
0
} AM
4 AM
o
o
!
o
!
s AM
0
0
1
1
2
6 AM
4
3
4
e
19
7 AM
6
e
14
10
38
sAll
3
2
#
«
!9
9 M
4
4
2
!
!!
2
1
4
0
7
!!
2
_
!2
!2 PM
2
\
2
6
12
1 PM
3
3
3
4
13
2 PM
.
,
:
_
15
3 RM
2
3
6
2
13
4 PM
3
4
6
2
!s
s PM
6
5
4
9
24
6 PM
e
1
3
4
1.6
7 PM
2
2
2
5
11
0 r
1
s
3
3
12
9 PM
2
3
1
2
e
10 PM
1
2
1
0
4
11 PM
0
0
1
1
2
TOTAL VOLUME IS 257 VEHICLES.
ErLH a KRr E gTs 4 HICLE%
A DASH MEN S HOUR' VOLUME < 2
PEAK HOURS:
HORNING PEAK HOUR VOLUME OF 40 BEGINS AT 7:15 AM t 16 &>
Eve INO PEAK HOUR VOLUME of 26 BEGINS AT 5:15 PM < 10 �>
DATA COLLECTION BEGAN AT 12 AM ON WEDNESD Y, AFRIL 10, 1991.
APPENDIX B
1935 HCM: UNSIGNALIZED ItJTEPSECTIONS
[Y.FYYAYY[ZCY.Y.C[C.YC.. CYFYCYCCCYYYCC.CC[CC[.
CYYYC[
1 OENT IF 17 NC- INFORMATION
------------------------ _---------------
_____________________________
:Vc?A3E F:UNu I":G _. ___. ���� =iF.=_ 7
oEAK HOUR FACTOR .....................
..
:REA POPULATION ......................
80000
NAME OF THE EAST/WEST zlTREET.........
ra�.erooin
NAME OF THE NORTH;S-CUTH ST REE-.......
sn;alc�
:LAME OF THE ANALYST ..................
mid
DATE OF THE ANALYSIS (mm/dd/YY7....._
SJ_6; F1
TIME %E6a^D ANALY_ED.................(aml
Pm ;9g1
rjTHER'. INFORMATION.... — --
INTERSECTION TYPE AND CONTROL
---------------------------------------------------------------------
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUNO: STOP SIGN
TRAFFIC VOLUMES
---------------------------------------------------------------------
EB WB NB SB
FFT ,5 1 �� 4
rHRU 0 5 150 456
FIGHT 1? 17
NLTm3ER O'r LANES AND LANE USAGE
.'IR
CAPACITY AND LEVEL-OF-ST-=RVICE
Page->
FT n'W-
'rAL
:11;V=•gENT
_ ,... ED
.ES ER Vr
-AT=
:?. r',;: �T,
.-.-
_.-.
CAPACITe
MOVEMENT
v(o :n)
... ._'i
..cony
❑c,=
_ � — . _._.
a
3H
MINOR STREET
21_31 r—�
E3 LEFT
14C
-0
THROUGH
0
17F
,-,n
'?C
l7rD
RIGHT
=_
734
'34
73. T_—
71[ 772 - ..
MINOR STREET
5�
WB LEFT
t
125
13
i19
117 0
THROUGH
6
157
152 >
152
- 146 - D
RIGHT
21
303
303 >
406 503
- 30 13 >3 A.
MAJOR STREET
38 LEFT
5
610
510
310
6G5 -
NB LEFT
24
506
506
506
482 A
IDENTIFYING INFORMATION
------------------------------------------------------------.
NAME OF THE EAST/WEST STREET...... wale -robin
NAME :'F THE NORTH"SOUTH STREET.... shields
DATE AND TIME OF THE ANALYSIS..... 5/26/91 Pm 1°91
OTHER. 'INFORMATION.... w/60 du
19c5 HCM: UNSIGNALIZED INTERSECTION$ -
RIX.RF:t.F IYYYYXtZ.FC:[FaRFX1.FYX:R4FX'YFXIF.Fa Yf.Yt.[t[Y.F XYYttlalRaaFa F.[FF at![.<
!0ENTiF'7:r* iNrOPPIATION
---------------------------------------------------------------------
A.VE=:AGE �iu�N RaG SPEE. MAJIJR STREET.. ._
.-EAK HOUR �4CTOR..................... .9
AREA T i ON ...................... 8O00O
;J .IMF THE EAST/Wt-T STREt......... waMerobin
a AME OF THE r., u9 TH/--0C T'. �TRE=T.. _ .... shields
NAME OF THE ANALYST. ................. mid
DATE OF THE ANALYSIS (mm/ddi YY)...... -/, 5/91
TIME PERI00 ANALYZED ................. am p'�,FD�
OTHER :NFORMATICN.... ./60 cu 1
INTERSECTION TYPE AND CONTROL ii
---------------------------------------------------------------------
INTERSECTION TYPE: 4—LEG
MAJOR STREET DIRECTION: NORTH; SOUTH
CONTROL TYPE E4ST80UND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
---------------------------------------------------------------------
-EER W8 NB 36
---- ---- ---- ----
LEF-
-HRII t 1 - 5'74
RIGHT 31 3
n)MBFR. OF LAN;-S ANn LONE U_?0L
---------------------------------------------------------------------
CAP AND
I - - �,F -
- - _
--
:E'_E-'. VE
-:T+'
MINOR. STREET
ypyou S•c.
_HR O,J G'r,r
..
. _
MINOR STREET
W8 1-EFT
_ 86
?0
'?L
7 7-
THR000H
1 105
10>
i0
RIGHT
33 565
565 >
566 .565
> 3 5=7 >A A
MAJOR STREET
S8 LEFT
33 409
409
=09
=75 3
N8 LEFT
6 547
547
547
zal A
IDENTIFYING iNFORMAATION
NAME OF THE EAST/WEST STREET. ... wee=robin
NAME OF THE NORrH i30UTH STREET.... shields
DATE AND TIME OF THE ANALYSIS...". 5/=8/91 am Rm 199t
OTHER INFORMATION.... w/60 du
APPENDIX C
® i
. �.
!
41!1P Pilo!!
INT11MR INTAIN S1?(;TION
A01l WHO AV 15-18, .000
Compendium of
Technical Papers
Institute Of Transportation Engineers
43rd Annual Meeting
Boise, Idaho
July 15-18, 1990
data used in my research was obtained in Fort Collins. The
conclusions of my research are supported in a similar study
conducted in Boston, Massachusetts. The signals at the
Hors etooth/Shields and the Harmony/Shields intersections also have
an impact on the queue of vehicles approaching the Shields/
Wakerobin intersection. It is my conclusion that the level of
service E shown in Table 1 should be tempered when considering the
additional operational information provided above. In my judgment,
the left —turn exits from Wakerobin Lane are in the level of service
D category.
There is a flashing school signal on Shields Street.
Wakerobin Lane falls within this school zone. There is an
elementary school and a junior high school located to the west of
Seneca Street. At the present time, students who must cross
Shields Street to attend either school are provided bus
transportation. However, during morning traffic counts it was
observed that a few students cross Shields (westbound) as either
pedestrians or cyclists. Comparing these ped/bike counts to the
school start times led to the conclusion that all these students
were in the junior high school. It was observed that vehicles
appeared to be travelling slower than 35 mph when the school
flashers were on and that they occasionally yielded to the
peds/bikes that desired to cross Shields Street. However, based
upon a speed zone evaluation conducted by the City of Fort Collins,
it is doubtful that traffic slowed down to the 20 mph school zone
speed. The ped/bike activity was considered to be light, even
during school times. During the morning peak hour of the street,
there were 6 peds and 18 bikes westbound. Given the amount of
students crossing Shields or walking 'parallel to Shields, it is
doubtful that the existing school signals meet technical warrants.
This judgment is further supported by the bus service that is
provided for all students who need to cross Shields Street to
access the junior high school.
The City of Fort Collins conducted a. signal warrant study at
the Shields/Wakerobin intersection in 1990. A copy of that study
is provided in Appendix D. This study indicates that Warrant 9,
Four Hour Volume and Warrant 11, Peak Hour Volume are met; and
Warrant 10, Peak Hour Delay may be met. These warrants are met
because Wakerobin Lane is the only direct access to Shields Street.
Most of the land in this area will likely be developed as
residential. There may be small parcels of commercial development,
but this development will likely occur near collector streets, It
is in the best interest of the City to limit the number of signals
along arterials like Shields Street to collector street
intersections. Troutman Parkway will be a collector. When the
west leg of Troutman is built to Seneca, along with some adjacent
development, it is likely that the Shields/Troutman intersection
would meet signal warrants. When the Troutman connection is made,
the Shields/Wakerobin intersection should again be checked for
signal warrants. It is my judgment that signals will not be
warranted at the Shields/Wakerobin intersection. When a signal is
installed at the Shields/Troutman intersection, the ped/bike
Intersection Delay At Unsignalized Intersections
Matthew J. Dolich, P.E.
Private Consultant
Loveland, Colorado
ABSTRACT
the technique described in the Hi fiwa
Capacity Manual, Special Report 209, Chapter
10, Unsignalized Intersections relates a calcu-
lated reserve capacity to level of service to it
Very unspecific description of expected delay.
T7te signalized intersection technique in the
Highway Capacity Manual relates level of
service to a range of stopped delay per vehicle.
It would seem to be consistent to relate level
of service at an unsignalized intersection to it
range of actual delay per approach vehicle.
This research provides some limited. data on
intersection delay related to the calculated
reserve capacity at selected T-intersections. At
the time traffic volumes were collected, iulcr-
section delays were also obtained for selected
movements. 'Ihe intetsection delay technique
is described in the Manual of Traffic En gib ncer-
ine Sludies, 11'E, 1.976, Chapter 8. By compar-
ing the calculated reserve capacity using the
counted traffic volumes to the observed aver-
age delay per approach vehicle, a table of
delays per approach vehicle could be deter-
mined. This, in turn, could be plotted to
determine a range of delay given a calculated
level of service.
INTRODUCTION
The means of evaluating the operation at an
unsignalized intersection is by determining the
level of service. The procedure in the 1985
Highway Capacity Manual (11CM) is primarily
145
taken from a German document (reference 1),
which uses gaps in the major traffic stream
utilized by vehicles crossing or turning through
that stream.
In the IICM, the level ol'setvice is related to
vehicle delay. This is especially trice in the
evaluation at a signalized intersection. Ilowev-
er, in the case of An bnsignalized intersection,
level of service is related to it nebulous mea-
sure of delay that can mean different things to
different people.
RESEARCI l Ol JEA TIVES
This research was tindr.rlaken to relate level of
scivice lip it definitive langv of vehicle delay
for the minor street Unllic flow. The objcc-
lives of like research were:
1. Compare the level of service (reserve
capacity) to a range of vehicle delay, in
seconds, liar the stopped traffic on (lie
minor street.
2. Determine a curve which best de-
scribes that range of vehicle delay.
RESEARCII APPROACH AND IAMFFA-
TIONS
Traffic counts were conducted at a number of
stop sign controlled intersections in Port
Collins, Colorado and Cheyenne, Wyoming.
These volumes were used to determine reserve
capacity in passenger cars per hour (pcph)
Intersection Delay At Unslgnaiized Intersections
according to procedures documented in the
I1CM. Ilighway capacity soflwiue developed
by the federal Ilighway Administration, U.S.-
D.O.T. was used to 1wi R►rna these calculations.
Along will] the tratlic volumes, vehicle delay
wits measured lirr each approach vehicle
according to ptocednres described in Chapter
8, "Intersection Delays," Mamgtl of Tiall_ic
3LIginecring Simlics.
1)ue to cliangi�s in critical gap size dine to
speed, number of lanes on the major street,
and number of legs Ill the intersedion, only T-
intctsections wcte evaluated. Further, in rill
cases, the mayor street was live lanes (4
through lanes and one left -turn lane) and the
speed limit on the major street wits 35 ntph.
INTERSECHON DMAY STUDY
At the time traffic volumes were obtained at
each of the interseclions, traffic delays were
also obtained for both right- and left -turning
vehicles from the minor street. Ilse methodol-
ogy used was to procedure which involved
counting the number of vehicles occupying nit
intersection approach (right: or left -turn lanes
constitute two nppionches) at successive time
intervals for the observation period. The
successive time interval selected was every 15
seconds. Each successive count rcprcacntcd
nit instantaneous density or number of vehicles
occupying the intersection approach per time
interval. 'these counts were atccompanicd by
total volume counts of each approach. The
average delay per vehicle its each lipplotach can
be expressed by:
D=NVV
where:
1) = Averngc, delay per approach vehicle
N = Total density count, or the sum of vehi-
cles observed (filling the periodic density
counts enclt t seconds
t ='fline intervals between density obscrvn-
tions (15 sectntds)
146
V = Totalvolume entering the ap-
proach during the study period.
A total of 61 fiflecn minute observations were
conducted. The :average delay per approach
vehicle for berth right and left turns for each
observation was tabulated. The calculated
delays were tounded to the nearest whole
second. 'the calculated delay per approach
vehicle for tight turns ranged from, 2 seconds
to 29 seconds. The mean was calculated at 9.9
seconds. The calculated delay per :approach
vehicle for left turns ranged from 6 seconds to
105 seconds. The mean was calculated it 27.0
seconds.
LEVEL OF S11MVICE CA,LCUI.ATION
Using the same 15 miliute periods from the
intersection delay study portion of this rc-
search, level of service calculations were per-
formed. Since the level of service calculation
requires hourly traffic, the volumes for each 15
minute period was factored by four. This not
only gives an hourly volume, but also assumes
a peak hour factor of 1.0.
Reserve capacity in passenger cars per hour
(pcph) was tabulated for the' right turns and
left turns for each observation. The calculated
reserve capacities ranged from 36 to 882 pcph
for the right turns. Ilie mean was calculated
at 565.5 pcph. Most of the calculated levels of
service were in the A category (> 400 pcph).
'he calculated reserve capacities ranged from -
75 to 241 pcph for the left turns. the mean
was calculated at 00.9 pcph. Most of the
calculated levels of service were in the D
category (IM-2M pcph), L- category (0-100
pcph), and F category (< 0 pcph).
ANALYSIS
Using the output data for right turns and left
turns from the delay study and the capacity
study, each corresponding observation point
was plotted and least squares graphical analysis
was performed.
Figure 1 shows the plot of calculaled reserve
capacity versus calculaled delay per approach
vehicle for the right turns. 'lice results of the
graphical analysis are also plotled. lay ealculal-
ing confidence interval as a range of delay per
approach for each calculated reserve capacity,
a reasonable prediction of delay can be made.
For example, a calculated reserve capacity of
400 pcph would yield a delay per right -turn
approach vehicle of 10-15
seconds.
Figure 2 shows the plot of calculated reserve
capacity versus calculated delay per approach
vehicle for left turns. The results of the.
graphical analysis are also plotted. Using the
confidence interval, a prediction of the range
of delay can be made. however, the data for
the left turns is all in the -100 to 4-2(H) range
of values. Therefore, the delay for left turns
is only valid for reserve capacities at the lower
end of the scale using the data considered in
this 'study. For example, a calculated reserve
capacity of 100 pcph would yield a delay per
left -turn approach vehicle of 12-22 seconds.
Tire size; of this range indicates that More data
is needed to reduce the prediction range.
CONCLUSIONS
Given the limited data obtained (61 observa-
tions), it appears as though the urelhododogy
can give a reasonable indication of tine range
of delay for vehicles entering a street at a slop
sign controlled T-intersection. I Iowever, more
data is needed to till in gaps:
1. Data is needed at intersections where
the right turns operate at levels of
service B, C, D, E.
2. Data is needed at intersections where
the left turns operate at levels of ser-
vice A, B, C.
At a number of the analyzed intersections,
there were signals upstream from tile: analyzed
intersections. Some of these signals were as
147
District 6 1990 Annual Meeting
close as 1/4 mile away. 'There wits no signal
progression pattern on the major steel.
llowever, it was noticed Il al Math operalion
and delay were iulducnced by vehicle clucues
cleated by the signals on file ►vain street. This
was not accounted I'or in al►y ill' the calcula-
lions or analyses, An elfort should be made to
select intersections which are not affected by
main street signals.
'111c statistical analysis oil this data and addi-
tional data should be much more rigorous than
that used in this analysis. The curves devel-
oped using all file data should be malhcn►ati-
cally derived and adequately tested using
accepted statistical practices.
The data presented is only for it T-intersection
with a four -lane (plus Icft-lnrn little) main
sheet with it posted sliced of 35 mph. Data
should also he collected at it number of plain
street posted speeds (45 n►ph and 55 mph).
Dafa should also be collected for it T-intersec-
tion on a two-lane shed al various Posted
speed limits.
II' llte additional data and analyses fora T-
inlersectioa point lowuid the validity of this
npploach, Ihcn similar (1r►tn shtndd
be collected and analyses pcthirrned at four-
Icg inlersectl►nis..
BIBLIOGRAPHY
Box, Paul 1). and Joseph C. Oppenla►ider,
PhD. Manual of `fraffc !:!Iginecring Sludies,
41h Edition. Arlington, Virginia: Institute of
Transportation Engineers, 1976, Pgs. 106-112.
Roess, Roger P. et al. Highway Capacity
Manual. Special Rcport 20L Washington,
D.C.: Tra is. porlation Itesearch Board, 1985,
Chapter 10.
REFERENCE
1. "Merkblatt for Lichtsignalanlagcn an Land-
strassen Ausgube 1972", Foi-schungsgesclischaft
Intersection Delay At Unsignalized Intersections
fur dus Strnsscnwcscn, Koln, Germany (1972).
149
District 6 1990 Annual Meeting
t00
RESERVE CAPACITY IPCPh)
COMPARISON OF RESERVE CAPACITY AND DELAY
FOR RIGIIT TURNS AT A T-INTERSECTION Flgure I
149
Intersection Delay At Unslgnalized Intersections
60
s
r
_.
..._.._,
0
r
--- -
.....
r
r
a
°a go
�
r l
s
r
Ir
on,
r
d 76-
tu zo
• r
.
10.
f
�000 Goo too Boo Boo 400 goo Zoo roo 0
(IESEOVB CAPACITY (Pcph)
COMPAf11SON OF nESEnvE CAPACITY AND DELAY
Fort LEFT 7unNS AT A TANTEIISECTION Pleura 2
150
ft•..'4•""M. r�}Trravv¢n.e�W f{�j,P/-y`Tt ta1U"a f e+v YN'.. f 'u' r�( �V �}M v14��a+ai;. Va94'SAL?�bf+HM`ytV�M�+'i�t'Ri?41f}trPA??M>AraY'�xm. wsa-
f
-• I nR.il �asl.�.- .... .4 r�M _Y t.. a.l - 1.:.1 � 3.. Jtw f. ,. .. 1 Y.l � r....-.Y �llJ1._idnlr la...[•. tYdu._.....:.l. i:. ud.c•e.�.._._ _. •�..
v
A HU1101)OIDO1 FOR I1S1N0 DELAY STUDY DATA
TO F.sTIHATE TUR F.XISTIHO All MIME LEVEL OF SERVICE
Ai WSICNALI7.F.D 1NTF.g9F.CT10Ns
By Harni lleffron (A)" and Oeorgy Bezkorovalny (H)b
The lovsL of service at unelgunlirad LnLnriven tlons is
often ovnrAtnted by the l9ni 111011way Cn1,Aclty
11m1un1 (IICN) m"tlodology. Ilia 111:11 Analysts for
unsiElva llzed intarnectinnS MAY Alyw s L1)9 P "r 1.09 F
operation wLth lnngthy delays And, prosiimnbly, long
queues. llow"vnr, from field obearvntJdn, the
interseetl"n functions relativnly wolf with abort
queues And minor delays nil thn appronch"A conttolled
by STOP signs And no d"lnyA CO mnlultn" traffic. Nary
reviewing agencies requite the lien of tho Ileli
methodology to determine Laval of servlcn. Ilowever,
ITCH states that "because tint m"llindoingies [for
calculating unslgnAllzad Level of enrvlce) result in a
qualitative evaluation of dnlny, It Is also
recommended, if possible, that name delay data be
collected. Tilts will allow for a better
qunutificstion And description of existing operating
conditions at the location undnr Study." ITCH does
not, however, Include a methodology to rolete delay
study results for an unsLgnalized intersection with a
level of service designation.
ITCH defines the level of service of an unsLgnalized
intersection usLng "reserve capacity", an
analytically -defined variable that is net easily
field -verified. 'ilia procedure is based on tits German
method of copeclty determination at rural
intersections. Tills method tins not been extensively
validated or calibrated for U.9. conditiyns, nor does
it estimate delay in quantitative torms.
Tills paper presents a mnthodnlogy to use delay study
data to determine the existing level of service slid to
estimate future operating coiidletans lit unsLgnalized
Intersections. In developing the methodology, delay
studies were performed lit more I:hnn 50 unrignnlized
T- Internet: tLatin In enAtnn) Sad annt'rnl linneenhueotts..
minor eppr"nehnn of than" 1.11tor""etl.nnn were
controlled by stall signs, yield mlpne and unnontrolled
(Implled yield). Ilia teaultA of those delay etinlinn
will also be enmpnred to the dalny cnlrplmtsd using
the IIGH ug)Signallzed Lntarsactl"O nunlyAls.
Tills paper rellns on tits existing 11CH methodnlogy as
the basis to estimate exlsl:ing And future level of
servlcn from dnlny data. It11t11n1lai1ges tics mail" Ln
the ITCH procndurn, tlo nxlsl:lug 1111H methodology for
unsLgnalized lntarsectlons 11111 nnntLnua to he
modified to yield results Clint batter Approximate
existing and future conditions.
a Trensportntlon Engineer
Bruce Campbell 6 AssocLates, Boston HA
b Vice President
Bruce Campbell 8 Associates, Boston HA
yd,yj9,(IAL.f2ED INTERSECTION DELAY
Delay was Adopted as a measure of effectiveness for
Signalized Intersections in the 1989 MCI for many
ronaonsl two tensors are that the concept of delay is
understand by the user community and delay can be
m"esnred In the field.3 The application of delay
for unflig"naliznd Intersections should follow this same
tenanning. The."res"rve capacity is related to
average vehicle dnlny using the following equation
from tits ITE llendbook2:
d - -- 1 (1)
(a - b)
d - average delay
a - service rate
If - side -street Arrival rate
Recognizing that capacity is the service rate and
volume to the arrival rate at an unsLgnalized
intersection, this formula shows that the average
vehicle delay is the reciprocal of reserve capacity.
Tile average seconds of delay per vehicle is calculated
using the following equation:
Average Belay (sae/veh) . 3600 (set/hr) (2)
Reserve cepselty (veh/hr)
Table I allows the level of service designations which
correspond to reserve capacity and average vehicle
delay. Because the overage delay per vehicle
approaches infinity as the reserve capacity goes to
,tire, IDS F will be defined by any delay over 60
soconds. The Average delay values for unsignalized
Intersections shown in Table 1 are very similar to the
delay values used to define the level of service of
elpnnllzed Lntarsectione. Table 1 is taken from Table
10.3 in tl,e ITCH.
Table 1
L"vnl•af-se.rvicn Criteria
For Unslgnallzed Intersections
Average **
Level of Reserve Capnetty Stopped Delay
,gytvlce (Pass Gare_pQ1`118ii). (sec/veh)
A > 'too < 9.0
g 300 - 399 9.1 to 12.0
C 460 - 299 12.1 to 18.0
D 100 - 199 18.1 to 36.0
E 0 - 99 36.1 to 60.0
F * > 60.0
* Demand exceeds capacity: extreme delays will be
encountered
** Calculated from Equation (2)
Be
MEASURED DM AY A CAlts IEIVDEIAY
Delay studies At uneignatlzed Int"rnectlouR Ara
relatively envy to perform end onn b" perfnrmed In
conjunction with a tinning mriv A,p"lit count all. low
volume Lntereections. ThA ohsntver mennurRs the time
between whoa A vehlcl" stops for A sl:op sign or
conflicting traffic And pulle onto the major ete"at.
The maAsur"mant Lnclud"s LIT" time waiting In queue.
Tile stopped delay to measured far rsi(dom vehicles
turning left or right from tha minor atre"t or turning
left from the major attest. '[hit nvernge delay during
the peek hour in calculated "Ring A modified
signalized intersection delay ap(iation:
Average Coley teat/veh) • latiLL900Y.A-960_ (�)
Rumher of Cb/orvatlono
For locations with a shared Inn" for left And right
turns on the minor street, tha stopped delay for each
movement elaould be kept RepArnt" if future conditions
will be projected from the dnto allies the level of
service of each movement is calculated separately and
then combined an a shnro"d tell" movement. Special
consideration, discussed later, should b" given to
shared lane approaches whore the right turn delay will
be increased by a high left turn volume. The existing
level of service for the shored lane to the weighted
average of the combined movements;.
Bruce Campbell 6 Associates performed delay studles lit
more than 50 unnlguaiized lnt"rRections Ill eastern and
central Hnasochusette. For all study locntions, a
traffic count was Alan periormnd, And the level of
service was calculnted using thn ITCH methodology. To
date, only A Eew delay studlnn have been porfo'rinod at
4=legged LntersectiotiA, no only the data for
T- intersections art, lnclud"d In this paper. The
average dalsy per vehicle wns calculated using
equation (3). FLguras 1 through 3 compnre the results
of the mensurod delay Atilt the Anlculated delay. The
curves are from regrannlmt aquntions relnl:lug
conflicting flow and nvnrngA dotty. At this point
there hnv" been no Attempts to correlate the delay
data to another variable Runll As speed, movement
demand or type of control.
For all three critical mnvnel"OR At nu title Ignat Ized
lntersectLen-•the Loft turd from till' minor "treat,
right turn from the mtnor strsst end Left turn from
the major strontr-Elie mensur"d (inlay woe found to be
shorter than the calculated delay. Tlioee data suggest
that drivers are selecting meutller gnpR than those
recommended In the 1985 ITCH. using the methodology
described below to buck-enlculate to the critical gap,
It was found that lit aver 60 percent of the loentiona,
the critical gnp for both thn minor left end right
turn movements was loge than 6.0 seconds.
It was originally suspected that the smaller gap size
determined for the study locations would result in
higher accidents rates at thnae locations. Ilowever,
most of the intersectlone studied find accident rates
less then 0.5 Acc/Hillion Entering Vehicles, and none
Iced accident rates over 2.0 Ace/HEV. In
Hag9a161tU9etts, intersections with an accident rate of
less than 2.0 are not considered high accident
locations.
tea
ro
ee
to
so
•e
ro
30
It
11
FIGURE I
_._ Ithaie•mIJ
CON EICI ING FLOW
(IGURE 2
e e.• e.t e.• 0.e�m.d.l 1._
itmm.
CON LICING ROW
f IGURE 3
gqhrUgLqjq fLOW_VS. AV F AGF LLA—Y
RKi IIIIAtN IRQM MPJCM:SIREEI
ro -
1•
re -
Ir -
m
le -
n-
17 " CUA
n • CA,
11
e
r
e-
e-
t
ED
e-
e ay e,, e.o e.e
lThadendsl
Co" LICI NG FLOW
Intersections with a sharod Inns on the minnr approach
provided conflicting resulte for the left Will right
turn movements. In many canes, the critlenl gnp
determined from tits delay date for the rig lit turn was
higher than the gnp determined for the minor left
turn. This phenomenon Is most Likely this to the time
a right turner spends waiting in queue behind a left
turner. Because of tits queue, the measured delays for
the two He veers not drnmatically different.
Since the critical gnp calculation relies on the
movement's conflicting flow, the right turn gnp
calculates to a higher value than the left turn gnp.
Cenerally, the minor left turn to the most critical
movement at an intersection, aid the delay data for
the left turn Is not significantly affected by a
shared late@. Yn retrospect, if dalny data
measurements did not include stopped delays in a
queue, then the calculated gopn would be higher for
left turns than right turns in nil instances.
However, not recording delays In a queue would give ail
unfair representation of existing field conditions.
To further illustrate tlfe allayed Lane phenomenon
offecting right -turning vehicles, the results in
Figures 1 and 2 allow a large di;eparity between the
calculated dolnys vs, mmax6red delays. Ilowever, in
the case of right -turning vehlolam, tiro manntered
delays were only 2-3 macateds Iona thnn the enlculWted
delays. The presence of LeF.t•I:urnlug vehlalea In the
shared Irma lend, most likely, a nlgnLfIennt Impact out
the delay vnluon tecordnd for right-turutng velticlea.
Further resenrch on shared -lane approaches IN needed.
ESTIHATIHC Flllllft -FV "r—aEIMUR
The following procedure In sagrnated to estLmnts
future level of service from nxlnt.ing delay (intoit
relies on the existing fIcH mnlhndology, still hnstenlly
back-enlculates from delay to nnpncity to determine
the gnp being accepted by drivers. Once ties gnp IN
determined, the future capacity and level of service
can be estimated using the some gnp.
The capacity for an unelgnnlixad intersection movement
can be determined from delay by rearranging equation
(2) as follows:
Capacity (veh/hr) • ]622 (ee AS-Ii _� # Side Street Demand «)
Average Delay (see/vah)
The IIcH equations relate critical gap to "potential
capacity." The potential cnpnclty for the left turn
from the major street need right turn from the minor
street are the same as capacity, but tits capacity of
the minor left turn nends to be converted to potential
capacity discounting the impndnnties factor of the mnnor
left turn. Tim impednnce factor to determined using
the following equation (the vnr.iabie named
correspond to the variabLas in II(;It):
j 1.2052 (5)
1 — I MOM 100 x
I
p4
i — Impedance Factor
V4 - Left turn volume from major street
Cleft — Capacity of left turn from major street
The potential capacity of the minor left turn is then
calculated using:
Cpy 1
C y — Potential capacity of the minor left turn
Cray - Actual capacity of the minor left turn
(determined from delay data)
Using Figure 10-0 it the 1985 ITCH, the critical gap
can be estimated from the potential capacity and
conflicting flow. Alternatively, the equations in
Karsten C. Banns, article "The Potential Capacity of
Unsignallzed Intersections" (ITE Journal, October
1967, pp. 43-46.) can be used to determine tite gnp.
Tile estimated critical gnp may be lower than 4.0
seconds for low volume locatfons, but it is
recommended that 4.0 be the minimum gap used. HCH's
Figure 10-3 also shows tile minimum critical minimucritical gap to be
4.0 seconds.
Once tile, critical gnp is estimated from the delay
data, the future level of service at a location is
determined using the standard RCN methodology. This
methodology is not recommended for intersections with
high accident experience, or where vehicles on the
side street are foreiig a r,np in the major street
traffic stream. The following in an example of this
mathodology's application:
F.KAIIPLEt
A dolny study and turning movement count were
pnrfortnnd at tl(e T-Intersection of Lincoln Avenue and
Brtntow street in Saugus, Massachusetts. The PH peak
haler turn Gig movement volumes and vehicle delays are
nnnmerized below:
Average
Peak Hour Conflicting Delay per Maximum Simple
Movement yotume Flow Vehicle Detily Site
Minor Left to/ 1221 13.7 64 92
Miner light 33 673 3.4 28 31
Major left 36 633 3.8 14 13
According to the ITCH methodology, the left turn from
Bristow Street to Lincoln Avenue operates at LOS F.
The delay study data, however, show that the left turn
operates at LDS C.
Tile capacity of each movement is calculated using
equation (4).
Movement Demand Capacity.
Hiner Left 101 vph 370 vph
Minor Right 33 760
Hajor Left 36 983
The potential cnpnclty of the minor left turn is
calculated using the impedance factor from equation
(5). The impedance factor is determined from the
demand and capacity of the major left turn,
0.0038(100 x_3¢)1.2052 — 0.98
983
need potential capacity, Cp7 — 370 - 378 vph
0.98
-3-
The conflicting flow of the minor left turn - 12.21
vph. Using Figure 10-3 its the IICN, a critical gap of
approximately 4.5 seconds is located for a potential
capacity of 378 and a conflicting flow of 1227. These
steps are illustrated in the flow chart in Figure 4.
Under the future conditions, the conflicting flow is
estimated to increase to 1400 vph, and the minor left
turn demand will increase to 170 vph. The future
potential capacity located on Figure 10-3 1s.300 vph
for a gap of 4.5 seconds end conflicting flow of 1400
vph.
Ilia actual cspncity nccoutnts for the impedance factor
(for tills example the lmpatlntna factor is Assumed to
be 0.98).
Cm1 - 300 x 0,9" — 294 vph
The reserve capacity — 294 • 110 — 124 vplt,
and the average delay is anlemnlated using equation (2),
Delay " M 29.0 net.
The level of service for the future conditions will be
LOS D.
CONCLUSION
The methodology presented Ln this paper provides one
way to quantity the Operation tit all unsLgnnlized Inter-
section when the ITCH mothodningy does not correlate
with field observations. Future operating conditions
can also be defined oil tlin heels of existing
conditions delay data. The delay methodology should
not be used for intersections with high accident
experience or where vehicles on the side street are
forcing a gap in the major street traffic stream.
Further research is needed for intersections with a
shared lane on the minor approach since the right turn
delay is affected by the left turn movement. Date
collected for the left turn movement on a shared lane
approach should not be significantly affected.
Delay is a measure of effectiveness that should be
applied to unslgnalized intnrsections because it le
easily measured and also enetly understood. Future
revisions of the HCH.methodology should include
delay.
REEF 11 M01
1. Transportation Rannnrrh Board. NatlolIAL Resenrch
Council, "Resenrch prnhlnm Stntomentat iitghwny
Capacity", Trnnaporation Research Clrnulnr Number
319. Washington D.O., Juue 1987, page 27.
2. Institute of Trnisparntlnn Enginecre.
Ir0I1sV9LPtl.9U_4(ItI�L9�L;La_BDC 499536�on book.
Prentiss Hall Inc.1 1982,.pp.
3. Roesa, Roger P. end HC.rllnne. William R. "Changing
Concepts of l.evel of Service in the 1985 Illghway
Cnpnetty Manual: Some rxnmples," 11E Journal, may
1987, pp. 27.31.
FIGURE 4
ESTIHATINC FUTURE LOS FLOW CHART
Existing Future
Conditions Conditions
Measure Future IDS
be I I Table 1
8 ry Avg. Delay
Per Vehicle Per Vehicle
Equation (3) Equation (-2)
Capacity of I Reserve Cap.
Movement Subtract
Equation (A) I Demand
Impedance Actual
Factor Capacity
Equation (5) 1 Equation (6)
Potential Potential
Capacity Capacity from
Equation (6) ITCH Fig. 10-3
Critical Cap Assume Some
IICN FLB• Critical Cap
in_t for Future
4, Reese, Karsten C. "The Potential Capacity of
Unsignnlized Intersections", j1E Journal, October,
1987, pp, 43-46.
5. Transportation Research Board, National Research
Council. LIIetLway jt ; Special Report
209. washington D.C., 1985.
v
b
(school) crossing should be moved to this location. When this
occurs, the flashing school zone signals should be removed from
Shields Street.
The proposed development of the Platt Property is proposed to
occur in phases. Phase 1 will involve at least 60 dwelling units.
The remaining 55 dwelling units would be developed based upon
economic development criteria. Table 2 shows the trip generation
from the proposed development. Figure 2 shows the 1993 peak hour
traffic with the additional traffic assigned to this intersection
from the proposed development. Background traffic on Shields
Street was factored at 2 percent per year. Table 3 shows the peak
hour operation at the Shields/Wakerobin intersection. Calculation
forms are provided in Appendix E. According to the 1965 HCM
technique, the eastbound left -turn exits from Wakerobin Lane are
in the level of service E category. Applying the research
discussed earlier shows that, in the morning peak hour, the delay
to the eastbound left -turn exits is 25-35 seconds; and, in the
afternoon peak hour, the delay to the eastbound left -turn exits is
23-33 seconds. That is 3 seconds more than the respective delays
shown using the existing traff-ic. The increase in delay is not
significant. It is my conclusion that the actual level of service
of these left -turn exits is in the level of service D category.
From this analysis, I conclude that 60 dwelling units can be
developed without considering building Troutman from Seneca to
Shields.
From the development of 60 dwelling units, an analysis of the
remaining 55 dwelling units was conducted on an incremental basis.
Figure 3 shows the 1995 peak hour traffic with the traffic from an
additional 10 dwelling units added to the Shields/Wakerobin
intersection. Background traffic on Shields Street was factored
by 2 percent per year. Table 4 shows the peak hour operation at
the Shields/Wakerobin intersection. Calculation forms are provided
in Appendix F. This analysis coupled with the research discussed
earlier shows that this is the limit of development before Troutman
Parkway should be completed between Seneca and Shields. Without
Troutman Parkway, the Shields/Wakerobin intersection would operate
unacceptably if more than 70 dwelling units are developed.
City staff requested an analysis of whether the two lane
portion of Shields Street (roughly between Troutman and Horsetooth)
could accommodate the increase in traffic. With the 70 dwelling
units level of development, the two way traffic on this segment
will be approximately 1230 vehicles per hour in the morning peak
hour and 1460 vehicles per hour in the afternoon peak hour. Both
of these volumes are within acceptable level of service categories.
The critical area is in the northbound direction at the Shields/
Horsetooth intersection. If the south approach were a single lane,
then the operation would be unacceptable. However, the south
approach has a left -turn lane, two through lanes, and a right -turn
lane which create acceptable operation at the intersection itself.
APPENDIX D
SHIELDS ST.
WAKEROBIN
TRAFFIC SIGNAL WARRANT EVALUATION
INTRODUCTION
This review is based on the methodology presented in the Manual
on Uniform Traffic Control Devices (MUTCD), 1978, as amended by
the Federal Highway Administration. Please refer to part 4C of
that manual.
The intersection under study has the following characteristics:
The 85th percentile speed on the
Existing traffic control is ^ .
Daily tr�ffic volume of [141495]
WEDNESDAY/ APRIL 101 1991.
Estimated annual traffic volume
1- INTERSECTING TRAFFIC VOLUMES
main street is [ 35 ] MPH.
SIDE STREET STOP.
was counted on
is [5,290°675] vehicles.
The installation of a traHic signal may be necessary to control
an intersection with large volumes of conflicting traffic. The
required traffic Yolu.mes must be present for at least 8 hours of
an average weekday. The minimum volumes vary according to the
number of lanes on the intersecting streets, the speed of traffic
on the main street, and the community size.
Number of hours required traffic present � 1
Warrant 1 is NOT SATISFIED.
2. INTERRUPTION OF CONTINUOUS TRAFFIC
On major streets with high traffic volume, it may be necessary to
use traffic signal control to provide an adequate number of gaps
in traffic to allow vehicles to enter from a side street. The
application of this warrant is identical to that of warrant 11
above.
Number of hours required traffic present = 7
Warrant 2 is NOT SATISFIED~
3. CROSSING PEDESTRIAN TRAFFIC
This warrant is similar to warrant 29 but is intended to identify
locations where additional gaps are needed to provide safe pedes-
trian crossing of a major street. A signal installed solely for
pedestrians should use a fully actU'ated controller andv if in a
signal system, be coordinated with that system. A signal in-
stalled only under this warrant shall include pedestrian signals.
When installed at a midblock location, additional restrictions
may apply (See section 4C~5)°
Number of hours required traffic present = 0
Warrant 3 is NOT APPLICABLE.
4. SCHOOL CROSSING
An established school crossing may require signal protection if
an engineering study reveals that there is less than one gap per
minute during the period of crossing usage. The restrictions on
Signals installed under this warrant are similar to those of
warrant 3.
WARRANT 4 IS NOT SATISFIED,
A traffic signal may occasionally be used to maintain vehicle
grouping in coordinated a system. Such a signal should not be
within 1,000 FT of adjacent signalized intersectiors in the
system -
Warrant 5 is NOT APPLICABLE.
6. ACCIDENT PREVENTION
Many traffic signals are installed on the premise of reducing
accidents; however, it must be recognized that signals may
actually increase some types of accidents. The result is often
contrary to the intended goal. Fo4r conditions must be met
before a signal is installed solely to reduce accidents-
(1) There has been five or more accidents of types
preventable by traffic signals in the last 12
months;
(2) at least one volume requirement of warrant 8
must be satisfied;
(3) traffic progression would not be seriously
disrupted, and
(4) less restrictive solutions have been tried and
enforced with unsatisfactory results.
A signal installed solely under this warrant should be traffic
Total number of accidents = 0
Number of preventable accidents 0
Accident rate is 0 per million vehicles
Number of warrant B volume requirements met = 1
Parts 1 and 2 are NOT SATISFIED.
/
7. TRAFFIC SYSTEM OPERATION
Tr'affic signal control may be used to encourage concentration
and organization of vehicles on the major street network. Such
a signal may be installed at the intersecticn of two major
routes as defined by section 4C--9 of the MUTCD, with a total
volume of 1300 vehicles during the typical peak weekday hourj or
for fiye (5} weekend hours.
Warrant T is NOT APPLICAGLE.
S. COMBINATION OF WARRANTS
In exceptional cases, signal control may be iustified where no
single warrant is satisfied, but where at least two of warrants
1' 2, or 3 are met when the required volumes are reduced to 80%
cc normal. Adequate trial of oHher Measures which cause less
delay and inconveni�nce must be tried and enforced first.
Number of warrants satisfied at the 80% level := 1
Volume requiremonts for warrant 8 are NOT SATISFIED.
9. FCUR HOUR VOLUME W�RRANT
This warrant was approved as an amendment to the MUTCD on
December 31` 1984. This warrant is similar to warrant 1, except
that the required traffic volumes must be present for at least
four hours of an average weekday. The traffic volumes required
are based on curves (Figures 4~3 & 4-4) shown in the MUTCD.
Warrant 9 is SATISFIED.
10. PEAK HOUR DELAY
This warrant was approved as an amendment to the MUTCD on
December 31, 1984. This warrant is intended for application
where traffic conditions will cause undue delay to traffic
entering or crossing the main street. The peak hour delay
warrant is satisfied when the following conditions exist for
one hour (any four consecutive 15-minute periods) of an average
day:
(1) The total delay by the traffic on a side street
controlled by a stop sign eqqals or exceeds four
vehicle -hours for a one —lane approach and five
vehicle -hours -for a two-Ia.ne approach;
(2) the volume on the side street equals or exceeds
100 VPH for one moving laiie of traffic and
150 VPH for two moving lanes;
(3) the total traffic volume serviced during 1 hour
equals or exceeds 800 VPH for an intersection
with four (or more) approaches or 650 VPH for
three approaches.
Warrant - 10
Part 1 ~ Delay to be determined by traffic engineer~
Part 2 ~ SATISFIED
Part 7 � SATISFIEF�
11. PEAK HOUR VOLUME
This warrant was approved as an amendment to the MUTCD on
Dscember 31/ 1984- This warrant applies to traffic entering
from the minor street which encounters undue delay crossing the
main street. This warrant is satisfied when the main street
and side street traffic volumes satisfy the curves (Figures 4~5
and 4-6) shown in the MUTCD.
Warrant 11 IS SATISFIED.
`"N14..
TABLE 1
TWENTY ... FOUR
HOUR VEHICULAR
TRAFFIC
EVALUATD]N
WARRANTS
1,2 AND
8
HOUR
MAIN ST.
SIDE ST.
WARRANT
WARRANT
WARR4NT
S ^
OF
DAY
VOLUME
-------------
VOLUME
1
2
PART 1
PART 2
1 12
AM
48
2
1
AM
54
1
2
AM
16
1
3
AM
22
1
4
AM
42
1
5
AM
138
2
6
AM
472
19
nAIN
I'll AlN
7
AM
1129
�7
N MA�
BOTH~
MAIN
BOTH-
8
AM
946
53
MAIN
BOTH-
MAIN
BOTH--
9
AM
669
27
MAIN
IV! AI111
MAIN
M/`1IN
10
AM
683
21
MAIN
MAIH
MAIN
MAIN
11
AM
731
105
BOTH~-
BOTH~-
BOTH
E0TH~
12
PM
755
32
MAIN
MAIINI
MAIN
MAIM
1
PM
654
26
MAIN
MAIN
MAIN
MAIN
2
PM
832
54
MAIN�'
BOTH-
MAIN
2OTH�
3
PM
1023
75
MAIN
BOTH-
MAIN
BOTH'~
4
PM
1095
91
MAIN
BOTH'
BOTH~
BOTH-
5
PM
1202
41
MAIN
MAIN
MAIN
MAIN
6
PM
1036
72
MAIN
BOTH-
MAIN
BOTB-
7
PM
564
20
MAIN
MAIN
MAIN
8
PH
505
83
MAIN
SIDE
MAIN
BOTH-
9
PM
448
8
MAIN
MAIN
10
PM
239
4
11
PM
140
2
REQUIRED
VOLUMES:
MAIN STREET
420
830
336
504
SIDE STREET
105
53
84
42
. SHIELDS ST.
WAKEROBIN
SIGNAL WARRANT STUDY
|
****
MAIN STREET
****
| ****
SIDE STREET
****
| INTER~
HOUR |
TOTAL
PEAK
BIAS
| TOTAL
PEAK
PEAK
| SECTION
OF
DAY |
VOLUME
DIRECTN
PRCNT
| VOLUME
DIRECTN
VOLUME
| VOLUME
12
AM
48
SOUTH
52
3
EAST
2
51
1
AM
54
NORTH
54
2
EVEN
1
5,:
2
AM
16
NORTH
63
1
EAST
1
17
3
AM
22
NORTH
55
1
WEST
1
23
4
AM
42
SOUTH
71
1
WEST
1
43
5
AM
138
SOUTH
64
4
EVEN
2
142
6
AM
472
SOUTH
61
27
WEST
19
49�
7
AM
1129
SOUTH
54
115
EAST.
77
1244
3
AM
946
SOUTH
51
72
EAST
53
1C18
9
AM
669
EOUTH
52
38
EAST
27
70�
10
AM
683
SOUTH
51
28
EAST
21
711
11
AM
731
NORTH
52
117
EAST
105
84G
12
PM
755
SOUTH
50
44
EAST
32
799
1
PM
654
SOUTH
54
39
EAST
26
693
2
PM
832
NORTH
51
69
EAST
54
901
3
PM
1023
SOUTH
53
Be
EAST
75
1111
4
PM
1095
NORTH
53
106
EAST
91
1201
5
PM
1202
NORTH
52
65
EAST
41
1267
6
PM
1036
NORTH
52
Be
EAST
72
1124
7
PM
564
NORTH
56
31
EAST
20
595
8
PM
505
NORTH
95
EAST
83
600
9
PM
448
NORTH
57
11
WEST
8
459
10
PM
239
NORTH
63
5
WEST
4
244
11
PM
140
NORTH
67
2
WEST
2
142
TOTAL INTERSECTION VOLUME IS 14,495
MAIN STREET TOTAL VOLUME IS 13,443
NORTHBOUND APPROACH IS 61742 ( 50 I)
SOUTHBODN[} APPROACH IS 6v702 ( 50 I)
SIDE STREET TOTAL VOLUME IS 1o052
EASTBOUND APPROACH IS 795 ( 76 %)
WESTBOUND APPROACH IS 257 ( 24 %)
REPORT PRODUCED THVRSDAY, APR%L 11, 1791"
COUNTS TAKEN ON WEDNESDAY; APBIL 10, 1991.
APPENDIX E
1985 HCM: HNSIGNALiZED INTERSECTIONS Page-1
♦.tt.<ztai;YYYZYZY%It;.Y{zY;Y#:kt'[tiY.tz;<z<t'<kYYtzYYz zY YtizF z;;.%YY;#Y;.<Y.
7{'E'+TiFYL'1G iNFCRM4TIf:,
---------------------------------------------------------------------
..................... .9
AREA POPULATION ....................... 30000
NAME OF THE EAST/WEST STREET......... Nakerooin
`LAME THE NORTH/=0'JTH STREET....... sHie'ds
NAME OF THE ANALYST .................. :mid c
DATE OF THE ANALYSIS (mm/dd/YY)-....- 5/?6/91
T IME. PERIOD ANALYZED ................. 3m om le�
OTHER INFORMATION.... w/60 du
IN TERSECTICN TYPE AND CONTROL
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRE',TION: NORTH/SOUTH
CONTROL TYPE EASTBCUND': STOP SIGN
CCNTRC'_ TYPE WESTBOUND: STOP SIGN
'RAFFIC VOLUMES
_----------------------------------------------------
EE W5 N8 ts
---- ---- ---- ----
LEF-
THRU D 5 468 474
RIGHT 35 17 137
"1UMBER OF LANES AND LANE USA13E
---------------------------------------------------------------
,.. '.d8 11E
_______ _______ ______________
CAPACITY AND
---------------------------------------------------------------------
-EVEL-OF-=_RVICE
Paae->
RATE
_ ..
.,.�Ar.71
.71
::APAC;TY
--------
---------------------
------------ ---
MINOR STREET
-------
EB LEFT
._..
29
113
113
10 =
THROUGH
_
15:
SIGH?7
- ;:0
MINOR STREET
WB LEFT
1
112
103
103
19` D
THROUGH
6
145
139 >
139
> 133 > 'D
RIGHT
21
794
794
383 7^4
> 156 '73 >B A
MAJOR STREET
S8 LEFT
5
_ _
- -
:."
T90
NB LEFT
490
430
i9J
457
IDENTIFYING INFORMATION
NAME OF THE EAST/WEST STREET...... wake-o'oin
NAME OF THE NORTH/SCUTH STREET.... shields
DATE AND TIME OF THE ;r: A. �_ --- 5/76/F1 am Pm 199�
OTHER INFORMATION...
U N 5 .:j_-I . .NTEP:ECT. .. L _ce
�t}t a.<t<} } Ziit+i}iZ Zaiai<<}tRRRaaa tf /aR}RR}ttZ Y}Z Ri}t/}/ZtYY}Yft}Yi
----------------------------
----------------------------------------
=VEF-SE=.i'yn: 3 =-E__, '"A.,Ck _.TR==-..
PEAK HOUR ?AC TC=:..................... .9
AREA PCPULATiON ...................... 30000
'LAME THE EAST/'WE'S7 _"=7......... war.erobin
NAME Sr STREET....... shields
NAME OF THE ANALYST .................. amid
DATE OF THE ANALYSIS (mm/dd/yy)...... 5/25/9'
TAM= am O 1^9 SZ
OTHEk :flF^_:{�". ATI^`:.. w/50 du
INTERSECT* N TYo= AND :CNT=01_
___________________________________________________
INTERSEC'ICN 4-LEG
MAJOR _TR cT DIRECTION: NORTH/SOUTH
CONTROL TYPE EAST90'JND: STOP SIGN
CONTRD'_ TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
-------------------------------- ---------------------------------
__ W8 NB S3
---- ---- ---- ----
LEFT 36 2 24 11
THRU 1 1 749 S24
EIGHT .� 31 42
N c!MBF_R (Ic LANES a ND NE l 15AGE
_____________________________________________________________________
C
:oaflTY -ND
---------------------------------------------------------------------
!LEVEL-!!F-_ERVICE
- ca_"
-nT_N-
ACTUAL
F' CW-
:.=L
'<OVFT ENT
SHAkEO
_'ESERVE
_....-_
7
.�.__.-.
_ - _.
_.;-_.-
MOVEMENT
yr ;c c'n)
,- v'n)
________
_ __aid
_________ ____________
-c?n)
c
____________ ---
MINOR ST;.E=T
_______
z3-sa SK-
E_ _--T
44
72
64
64
__
THROU:..
97
J
_
R rr_y'
17
745
745
5u'1 745.
> a�_ -_. >A A
MINOR STREET
17-2T Crsc/
W8 LEFT
2
73
66
66
63
THROUGH
1
95
37 >
37
> 35
R iGHT
38
553
553 >
_43 553
> _. 5i5 -A
MAJOR STREET
S3 LEFT
33
393
393
393
360
N8 LEFT
29
52'
522
522
492 A
IDENTIFYING INFORMATION
------------------------------------------------------------
NAME OF THE EAST/WEST STREET...... wakerobin
NAME OF THE NORTH/SOUTH STREET.... shialds
CAT_ .AND TIME OF THE AN aI_v4:>..... 5/26/91 ; am 195�
OTHER iNFORMATI ON... �5u cu
0
Conclusion
It is concluded that up to 70 dwelling units can be developed
on the Platt Property and still maintain acceptable operation at
the Shields/Wakerobin intersection. Development greater than 70
dwelling units will precipitate the need for Troutman Parkway
between Seneca and Shields. The two lane segment of Shields Street
will operate acceptably with the devel.opment of 70 dwelling units
on the Platt Property and a normal (2% per year) increase in
background traffic on Shields Street.
APPENDIX F
UN�a
S:•_NALIZED T'4TERSECTiGNS ^^-e-1
...««........................................ ..... ..<. ..:.:..:.....:.....
:DE4T:-.ING IAT:_N
____________________________________________
>EAK HOUR FACTOR ..................... ..
AREA POPULATION ...................... 3000c
NAME OF THE /WEST _TP.ttT......... wa'.:ercDin
NAME CF THE ';OR T:H/SOUTH STREET....... snieICS
NAME OF THE ANALYST .................. mjd
DATE OF THE ANALYSIS (mm/dd/yy)..-.-- B/23/91
TIME PERIOD ANALY7-ED................ .(5em 199 7- du /
OTHER INFORMATION....
TNTER C-CTICN TYPE AND CONTROL
----------- ---------------- — ---------------------------
INTERSECTION TYPE: 4-LEG
MAJOR STREET D:RECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
EB 1143 NB SE
---- ---- ---- ----
LEFT 90 29 4
TH P.0 0 5 487 493
RIGHT 3C 17 3 13€
NU,i5ER OF LANES !NO LANE USAGE
__---------------------------------------- — --------------------
'- i•Ir plg Si
______- _______ -------
---------------------------------------
F L'OW- -- _ ")V�EMENT
—C 4 li-
MINOR STREE-
Eu '_EFT
1.
1-.0
09
RIGHT
46
i
713
MINOR STREET
WB LEFT
1
104
95
THROUGH
5
136
i30
R i.^oHT
21
-,a
784
MAJCR STREET
55 LEFT
-
530
530
NB LEFT
35
476
476
IDENTIFYING INFORMATION
J39e'_
-------------------------
3HA1ED RESERVE
LOS
SH
7.6 3ZP s—
log F
> 14> > 14_ - -
> 7 L2 713 > 566 565 >A A
r3 1.3 S�
95 93 E
130 > 123 > D
> 365 784 - 338 763 >B
580 575 A
476 440 A
NAME OF THE EAST/WEST STREET...... waKerobin
NAME OF THE NORTH/SOUTH STREET..... shieids
DAT= AND TIME OF THE ANAL`.5IS..... 5/23/91 Dm 99` `j6 du
CTHER INFORMATION....
,r
19)5 :70M. JNSII.;NAL: =D �:T=,R SEI,7:,_NS '.B ae-i
I RR)I .... as R_ _ RR.R t. I I .............. .............���
IDENTi F':INO iNF02MATION
---------------------------------------------------------------------
AV'=RAG= -!R+N TNG MAJOR S'c'E= .. ._
'EAK HOUR FACTOR ..................... .9
AREA. POPULATION ...................... 80000
NAME OF THE EAST/WEST STREET......... wakerebin
.NAME OF THE NORTH/SOUTH STREE7------- Shield -
NAME OF THE ANALYST .................. mid
DATE OF THE ANALYSIS (mm/dd/yy).._... 5/?8/91
TIME PERIOD ANALYZED ................. am ee
TO -u
OTHER INFORMATION....
INTERSECT TON TYPE AND CONTROL
-----------------------------------------------------------------
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
---------------------------------------------------------------------
E3 WB NB SB
____ ____ ____ ----
LEFT 38 2 30 27
THRU i 1 719 545
RIGHT 16 8 44
r11J;n5ER OF LANES .:NO LANE U"AGE
__________________________________________________________________
_____________________ _______
. AP 4C i-. ANO LEVcL _r-_=o- V:l: -.
;OTEN- AC 7_
AP AC
_______ _________________________________________
i
MINOR STREET
u-,s sw
_EFT 10 66
=R OIJGH 3v - -7 Z_
RIGHT 20 7C 7-4 > 495> 474 ?'.o >A A
MINOR STREET
I%-Z
WB LEFT 66 58 58 56
THROUGH t 85 77 77 > 76 > _
R *. GHi 33 641 541 > 522 v3 ., >A >
MAJOR STREET
58 LEFT 33 373 278 373 - 345 3
NB LEFT 37 505 505 505 469 A
IDENTIFYING INFORMATION
____________________________________________________________________
NAME OF THE EAST/WEST STREE'...... wav robin
NAME OF THE NORTH/SOUTH STREET.... shields
',-TE AND TIME 'JF THE ANALYSIS..... 5/28/91 , am o lO'0 du
OTHER 'NFORMATION_...
1991 AM / PM
May 21, 1991
93� 31 ►
'15/Z
18//3
Icn
r
1991 Daily Traffic
April 10 - 11, 1991
_, 33 go
"7015
WW 23/ 33
WAKEROBIN
WAKEROBIN
LP
N
N
RECENT TRAFFIC COUNTS
Figure 1
Table 1
Existing Peak Hour Operation
Level
of Service
Intersection
AM
PM
Shields/Wakerobin
EB LT
E
E
EB T/RT
A
C
WB LT
D
E
WB T/RT
B
A
SB LT
A
B
NB LT
A
A
Table 2
Trip Generation
Daily
A.M.
Peak
P.M.
Peak
Land Use
Trips
Trips
Trips
Trips
Trips
in
out
in
out
Platt Property
Phase 1 - 60 D.U.
600
13
33
38
22
Phase 2 - 55 D X .
550
12
30
35
20
Total
1150
25
63
73
42
0/ 1
35 / 14
1993 PEAK HOUR 'TRAFFIC
(60 du, 's DEVELOPED)
90/ 38
0/1
35/ I10
1995 PEAK HOUR TRAFFIC
(70 d.u.9s DEVELOPED)
WAKEROBIN
AM / PM
WAKEROBIN
AIM / PM
d
Figure 2
Rk I
Figure 3
Table 3
1993 Peak Hour Operation with Development Traffic (60D.U.)
Intersection
Shields/Wakerobin
Level of Service
AM PM
EB
LT
E E
EB
T/RT
A A
WB
LT
D E
WB
T/RT
B A
SB
LT
A B
NB
LT
A A
Table 4
1995 Peak Hour Operation with Development Traffic (70D.U.)
Level
of Service
Intersection
AM
PM
Shields/Wakerobin.
EB LT
F
E
EB T/RT
A
A
WB LT
E
E
WB T/RT
B
A
SB LT
A
B
NB LT
A
A
APPENDIX A