SR-506-003-05 (11)
Attachment F
th
Summary of 28 Street Volume and Speed Studies
Speed studies were conducted in February 1999. The speed comparison table below
shows both 85th percentile and average speeds on 20th, 23rd, Cloverfield (the streets
with speed humps), and 28th Street (with and without curb extensions) between Pico
Boulevard and Ocean Park Boulevard. Speed checks were made at several locations
along each street, including at each speed hump or traffic circle, and the sections of
streets between each hump or circle. Also shown on the table are the results of speed
studies taken in July 1999 along 28th Street after temporary curb extensions were
installed at each traffic circle.
The 85th percentile speed (or critical speed) is the speed at which 85% of the vehicles
are travelling at or below. The 85th percentile speed is also the speed at which speed
limits are typically set. On 20th, 23rd and Cloverfield, the 85th percentile speeds
ranged between 14 and 28 mph. Naturally, the lower speeds were registered at the
speed humps, and the higher speeds were between the humps. The overall average
85th percentile speeds for 20th, 23rd and Cloverfield between Pico Boulevard and
Ocean Park Boulevard, were 20.6 mph, 20.5 mph and 21.5 mph, respectively. The
average 85th percentile speed for the three streets was 20.9 mph.
On 28th Street, without curb extensions, between Pico and Ocean Park Boulevard, the
85th percentile speeds ranged between 17.5 and 29.5 mph. The overall average 85th
percentile speed was 22 mph. After curb extensions were installed, the speeds ranged
between 15.5 and 28.5 mph, with the overall average at 21.5 mph. As indicated, the
difference between traffic circle with and without curb extensions was 1/2 mph.
The table also compares average speeds along these streets. On 20th, 23rd and
Cloverfield, the average speeds ranged between 11.5 and 23.8 mph. Again, the lower
speeds were registered at the speed humps, and the higher speeds were between the
humps. The overall average speeds for 20th, 23rd and Cloverfield between Pico
Boulevard and Ocean Park Boulevard, were 17.5 mph, 17.4 mph and 18.1 mph,
respectively. The average speed for the three streets was 17.7 mph.
On 28th Street, without curb extensions, between Pico and Ocean Park the average
speeds ranged between 14.2 and 26.8-mph. The overall average speed was 20 mph.
After curb extensions were installed, the speeds ranged between 12.8 and 24.8 mph,
with the overall average at 18.1 mph. As indicated, the difference between traffic circle
with and without curb extensions was about 1.9 mph.
A comparison of traffic volumes, before and after traffic calming measures, was also
conducted in February of 1999. The counts were conducted for three days, Tuesday,
Wednesday and Thursday. The February traffic counts were compared to traffic counts
taken in December 1992 prior to the implementation of any traffic calming measures.
The December counts were utilized in the Sunset Park Traffic Plan EIR.
In December of 1992, 20th Street between Pico and Pearl had an average daily traffic
(ADT) count of 11,834 vehicles per day (vpd). The February 1999 counts showed a
range from 10,274 to 10,500 vpd for the three days counted. This results in a reduction
ranging between 1,334 and 1,560 vpd, or between 11.27 and 13.18%. Between Pearl
and Ocean Park, the 1992 count was 6,754 vpd, and the three day February counts
showed a range between 5,740 and 6,139 vpd, or a reduction ranging between 9.11
and 15.01%.
23rd Street between Pico and Pearl in 1999 had an ADT count of 8,658 vpd. The
February 1999 counts showed a range from 6,795 to 7,038 vpd for the three days
counted. This results in a reduction ranging between 1,620 and 1,863 vpd, or between
18.71 and 21.52%. Between Pearl and Ocean Park, the 1992 count was 10,452 vpd,
and the three day February counts showed a range between 8,085 and 8,297 vpd, or a
reduction ranging between 20.62 and 22.65%.
In 1992, Cloverfield Boulevard between Pico and Pearl had an ADT count of 9,112 vpd.
The February 1999 counts showed a range from 8,284 to 8,701 vpd for the three days
counted. This results in a reduction ranging between 411 and 828 vpd, or between 4.51
and 9.09%. Between Pearl and Ocean Park, the 1992 count was 6,676 vpd, and the
three day February counts showed a range between 5,992 and 6,476 vpd, or a
reduction ranging between 3.00 and 10.25%.
Finally, in December of 1992, 28th Street between Pico and Pearl had an ADT count of
5,875 vpd. The February 1999 counts showed a range from 5,108 to 5,634 vpd for the
three days counted. This results in a reduction ranging between 241 and 767 vpd or
between 4.10 and 13.06%. Between Pearl and Ocean Park, the 1992 count was 5,624
vpd, and the three day February counts showed a range between 5,481 and 5,644 vpd,
or a slight increase of 0.36% on one day to a reduction ranging between 2.42 and
2.54% on the other two days.
Traffic Volume Data
Deviation % Deviation
Street Segment Date ADT
from '92 from '92
20th St Pico Blvd to Pearl St Wed 12/9/1992 11,834
20th St Pico Blvd to Pearl St Tues 4/21/1998 10,780 -1,054 -8.91%
Wed 4/22/1998 10,491 -1,343 -11.35%
Thurs 4/23/1998 10,275 -1,559 -13.17%
20th St Pico Blvd to Pearl St Tues 2/2/1999 10,428 -1,406 -11.88%
Wed 2/3/1999 10,274 -1,560 -13.18%
Thurs 2/4/1999 10,500 -1,334 -11.27%
20th St Pearl St to Ocean Park Blvd Wed 12/9/1992 6,754
20th St Pearl St to Ocean Park Blvd Tues 4/21/1998 6,078 -676 -10.01%
Wed 4/22/1998 6,076 -678 -10.04%
Thurs 4/23/1998 5,980 -774 -11.46%
20th St Pearl St to Ocean Park Blvd Tues 2/2/1999 5,844 -910 -13.47%
Wed 2/3/1999 5,740 -1,014 -15.01%
Thurs 2/4/1999 6,139 -615 -9.11%
Deviation % Deviation
Street Segment Date ADT
from '92 from '92
23rd St Pico Blvd to Pearl St Wed 12/2/1992 8,658
23rd St Pico Blvd to Pearl St Tues 4/21/1998 7,022 -1,636 -18.90%
Wed 4/22/1998 7,154 -1,504 -17.37%
Thurs 4/23/1998 7,251 -1,407 -16.25%
23rd St Pico Blvd to Pearl St Tues 2/2/1999 6,795 -1,863 -21.52%
Wed 2/3/1999 6,926 -1,732 -20.00%
Thurs 2/4/1999 7,038 -1,620 -18.71%
23rd St Pearl St to Ocean Park Blvd Wed 12/2/1992 10,452
23rd St Pearl St to Ocean Park Blvd Tues 4/21/1998 8,367 -2,085 -19.95%
Wed 4/22/1998 8,228 -2,224 -21.28%
Thurs 4/23/1998 8,407 -2,045 -19.57%
23rd St Pearl St to Ocean Park Blvd Tues 2/2/1999 8,085 -2,367 -22.65%
Wed 2/3/1999 8,230 -2,222 -21.26%
Thurs 2/4/1999 8,297 -2,155 -20.62%
Deviation % Deviation
Street Segment Date ADT
from '92 from '92
Cloverfield Blvd Pico Blvd to Pearl St Tue 12/1/1992 9,112
Cloverfield Blvd Pico Blvd to Pearl St Tues 4/21/1998 8,444 -668 -7.33%
Wed 4/22/1998 8,490 -622 -6.83%
Thurs 4/23/1998 8,221 -891 -9.78%
Cloverfield Blvd Pico Blvd to Pearl St Tues 2/2/1999 8,284 -828 -9.09%
Wed 2/3/1999 8,308 -804 -8.82%
Thurs 2/4/1999 8,701 -411 -4.51%
Cloverfield Blvd Pearl St to Ocean Park Blvd Wed 12/2/1992 6,676
Cloverfield Blvd Pearl St to Ocean Park Blvd Tues 4/21/1998 6,334 -342 -5.12%
Wed 4/22/1998 6,334 -342 -5.12%
Thurs 4/23/1998 6,157 -519 -7.77%
Cloverfield Blvd Pearl St to Ocean Park Blvd Tues 2/2/1999 5,992 -684 -10.25%
Wed 2/3/1999 6,057 -619 -9.27%
Thurs 2/4/1999 6,476 -200 -3.00%
Deviation % Deviation
Street Segment Date ADT
from '92 from '92
28th St Pico Blvd to Pearl St Tue 12/1/1992 5,875
28th St Pico Blvd to Pearl St Tues 4/21/1998 6,129 254 4.32%
Wed 4/22/1998 6,188 313 5.33%
Thurs 4/23/1998 5,979 104 1.77%
28th St Pico Blvd to Pearl St Tues 11/17/1998 5,795 -80 -1.36%
Wed 11/18/1998 5,630 -245 -4.17%
Thurs 11/19/1998 5,833 -42 -0.71%
28th St Pico Blvd to Pearl St Tues 2/2/1999 5,108 -767 -13.06%
Wed 2/3/1999 5,568 -307 -5.23%
Thurs 2/4/1999 5,634 -241 -4.10%
28th St Pico Blvd to Pearl St Tues 7/6/1999 * 5,305 -674 -11.27%
Wed 7/7/1999 * 5,559 -420 -7.02%
Thurs 7/8/1999 * 5,305 -674 -11.27%
28th St Pearl St to Ocean Park Blvd Wed 12/2/1992 5,624
28th St Pearl St to Ocean Park Blvd Tues 4/21/1998 6,040 416 7.40%
Wed 4/22/1998 5,984 360 6.40%
Thurs 4/23/1998 5,813 189 3.36%
28th St Pearl St to Ocean Park Blvd Tues 11/17/1998 7,430 1,806 32.11%
Wed 11/18/1998 7,060 1,436 25.53%
Thurs 11/19/1998 7,519 1,895 33.69%
28th St Pearl St to Ocean Park Blvd Tues 2/2/1999 5,481 -143 -2.54%
Wed 2/3/1999 5,644 20 0.36%
Thurs 2/4/1999 5,488 -136 -2.42%
28th St Pearl St to Ocean Park Blvd Tues 7/6/1999 * 5,466 -347 -5.97%
Wed 7/7/1999 * 5,586 -227 -3.91%
Thurs 7/8/1999 * 5,297 -516 -8.88%
Speed Comparisons
85th Percentile Average
20th23rdClover Avg. 28th 28th 20th23rdClover Avg. 28th 28th
(with speed humps) (w/o ext) (w/ ext) (with speed humps) (w/o ext) (w ext)
Pico
Hump/Circle 15.5 18.5 17.5 17.2 18 19.5 13.5 13.8 13.3 13.5 15.4 15.5
Straight 27 25.5 26 26.2 27.5 28.5 23 22.4 23.4 22.9 24.1 24.8
Hump/Circle 18 15.5 18.5 17.3 18.5 17 14.7 11.7 14.8 13.7 15.5 13.8
Straight 25 24 24 24.3 26.5 23.5 22.2 22.2 21.3 21.9 23.6 20.4
Hump/Circle 18.5 15.5 19.5 17.8 24 15.5 15.6 12.3 15.6 14.5 20.8 12.8
Pearl
Hump/Circle 18 17 19.5 18.2 20.5 19.5 14.1 14.2 15.4 14.6 17.7 15.9
Straight 26 28 26.5 26.8 29.5 27.5 23.5 24.5 23.8 23.9 26.8 24.2
Hump/Circle 17.5 19.5 20 19 17.5 17.5 14 15.9 15.6 15.2 14.2 13.9
Straight 26 26.5 25.5 26 27.5 28 23.3 24.4 22.5 23.4 24.3 24.1
Hump/Circle 14 15 18 15.7 20.5 18.5 11.5 12.3 14.8 12.9 17.5 15.5
Ocean Park
AVERAGE 20.6 20.5 21.5 20.9 22 21.5 17.5 17.4 18.1 17.7 20 18.1
(speed comparisons2)