1
Reduced School Speed Limit Pilot Study - Parts I & II
School Safety Engineering
June 24th, 2008Janette Sadik-KhanCommissioner
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Pilot I• Pilot I : Began in 2005 to test reduced speed limits • 10 streets adjacent to schools in the Bronx• 8 out of 10 streets had “speed reducers”• Both 20 MPH and 15 MPH zones were tested
Signal15P.S. 279
Signal20St. Luke
Stop15P.S. 291
Signal15P.S. 110
Stop15P.S. 102
Signal20P.S. 30
SignalNo20M.S. 399
SignalNo20I.S. 166
Stop20P.S. 90
Signal15P.S. 79
Control at School Crosswalk
Speed Reducer (Hump)
Posted School Speed Limit (MPH)
School
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Pilot I – Preliminary Conclusions
• Reduced speed limits at schools may be effective on minor residential streets that do not already have existing speed reducers.
• Speed reducers are an effective tool (regardless of whether there is a lower speed limit opposed to a lower advisory speed) to ensurelow speeds (~20 mph) on minor residential streets.
• Reduced speed limits, in addition to existing speed reducers, have limited value.
Future Study on streets without speed reducers necessary in order to make more conclusive determination of the impact of reduced speed limits on streets without speed reducers.
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Pilot II 2007
Data Collected:• Vehicle speed and volume• Vehicle classification and turning movements• Pedestrian volume• One “Before” and two “After” periods (March 2007 – December 2007)• Two mid-week days for each period
Street Criteria:• One-way street with one travel lane adjacent to a school building• Street not designated a truck route or bus route• Length of block more than 200 feet• Located in advance of a designated school crosswalk, controlled by either a
traffic signal or a stop sign• No Speed Reducers
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Reduced Speed Zone: Test TreatmentEach Street received…• Flashing beacons during school hours 7AM – 4 PM
accompanied by reduced speed limit signs -20 MPH• Signs indicating Speed Zone Ahead• Signs indicating End Speed Zone
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Pilot II - Ten Schools
Signal
Stop Sign
Signal
Signal
Signal
Stop Sign
Signal
Signal
Signal
Signal
Type of Traffic Control at intersection with
school crosswalk
77th Street from 37th Road to 37th Avenue
42nd Avenue from 108th Street to 104th Street
Harman Street from Irving Avenue to Knickerbocker Avenue
Suydam Street between Irving Avenue and Wyckoff Street
Woodbine Street from Evergreen Avenue to Bushwick Avenue
Bleecker Avenue from Knickerbocker Avenue to Wilson Avenue
Willoughby Avenue from Cypress Avenue to Saint Nicholas Avenue
Hoffman Street from East 189th Street to East Fordham Road
Arthur Avenue from East 179th Street to East 180th Street
Walton Avenue from Mount Hope Place to East 176th Street
Street with Reduced Speed Limit
10
9
8
7
6
5
4
3
2
1
#
77-02 37th AvenuePS 69Queens
41-15 104th StreetPS 16Queens
220 Irving AvenuePS 86 Brooklyn
100 Irving AvenuePS 123 Brooklyn
88 Woodbine StreetIS/PS 299 Brooklyn
1300 Greene AvenueIS 383Brooklyn
1390 Willoughby AvenueIS 162 Brooklyn
2502 Lorillard PlaceMS 45 Bronx
57 East 179th StreetJHS 118 Bronx
1865 Morris AvenueJHS 117 Bronx
School AddressSchool Boro
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23.7
21.2
24.2
21.1
1819202122232425
MPH
ALL SCHOOOLS
AM BEFORE AM AFTER PM BEFORE PM AFTER
Pilot II Overall Results: Speeds Decreased in AM and PM
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Pilot II Overall Results: Speed Decreased Over Time
23.7
21.8
20.7
24.2
21.8
20.5
18
19
20
21
22
23
24
25
MPH
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
10
Pilot II Results: Change by Type of Traffic Control
at Intersection Downstream
23.4
21.1
24.1
21.0
24.8
21.6
24.8
21.6
18
20
22
24
26
Signal St op SignCont rol Device Downst ream
Signal vs. Stop Sign Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
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AM Speed Reduction (MPH)
2 2 . 5
2 0 . 5
2 8
2 1. 5
2 3 . 5
2 0 . 3
2 22 1. 5
2 5
2 2 . 5
2 4
2 0 . 5
2 2 2 2 . 3
2 3 . 5
2 2 . 5
2 4 . 5
2 0 . 8
2 2
2 0 . 0
16
18
20
22
24
26
28
30
MP
H
JHS 117 JHS 118 M S 45 IS 162 IS 383 IS/ PS 299 PS 123 PS 86 PS 16 PS 69
SCHOOLS AM BEFORE AM AFTER
12
25.0
20.0
29.5
20.8
24.5
20.0
23.0
20.0
24.0
22.5
24.0
21.0
22.0
23.323.0
22.5
25.5
20.8
21.5
20.3
16.0
18.0
20.0
22.0
24.0
26.0
28.0
30.0
MP
H
JHS 117 JHS 118 MS 45 IS 162 IS 383 IS/ PS299
PS 123 PS 86 PS 16 PS 69
S C H OOL PM BEFORE PM AFTER
PM Speed Reduction (MPH)
13
AM Speeds over time (MPH)
22.5
21
20
28
21.521.5
23.5
19.5
2122
22.5
20.5
25
24
21
24
22.5
18.5
2222.5
22
23.5
22.522.5
24.5
21
20.5
22
20.5
19.5
16
18
20
22
24
26
28
30
MP
H
JHS 117 JHS 118 MS 45 IS 162 IS 383 IS/ PS 299 PS 123 PS 86 PS 16 PS 69
SCHOOLS
AM BEFORE AM AFTER 1 AM AFTER 2
14
2 5
2 1
19
2 9 . 5
2 2
19 . 5
2 4 . 5
19
2 1
2 3
2 1. 5
18 . 5
2 4
2 4 . 5
2 0 . 5
2 4
2 2 . 5
19 . 5
2 2
2 3 . 5
2 3 2 32 2 . 5 2 2 . 5
2 5 . 5
2 1. 5
2 0
2 1. 5
19 . 5
2 1
16
18
20
22
24
26
28
30
MP
H
JHS 117 JHS 118 M S 45 IS 162 IS 383 IS/ P S 299 P S 123 PS 86 P S 16 PS 69
SCHOOLS
PM B EF OR E PM AFTER 1 PM AFTER 2
PM Speeds over time (MPH)
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Results: JHS 117, Bronx
22.521
20
25
2119
161820222426
JHS 117 Cha nge in Spe e ds ove r Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
22.520.5
25.0
20.0
1618202224262830
MPH
JHS 117
JHS 117 Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
AM speeds were reduced 8.9% from an average of 22.5 mph to 20.5 mph.
PM speeds were reduced 20% from an average of 25.0 mph to 20 mph.
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Results: JHS 118, Bronx
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21.5 21.5
29.5
2219.5
1618202224262830
JHS 118Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
28
21.5
29.5
20.8
1618202224262830
JHS 118Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
AM speeds were reduced 23.2 % from an average of 28 mph to 21.5 mph
PM speeds were reduced 29.7 % from an average of 29.5 mph to 20.8 mph
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Results : MS 45, Bronx
23.5
20.3
24.5
20.0
16
18
20
22
24
26
MPH
MS 45Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
23.5
19.521
24.5
1921
161820222426
MP
H
MS 45Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
AM speeds were reduced 13.6% from an average of 23.5 mph to 20.3 mph
PM speeds were reduced 18.4% from an average of 24.5 mph to 20 mph
18
22 22.5
20.5
2321.5
18.5
16
18
20
22
24
MP
H
IS 162Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
23.5
20.3
24.5
20.0
161820222426
MP
H
IS 162Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
AM speeds were reduced 2.3% from an average of 22 mph to 21.5mph
PM speeds were reduced 13% from an average of 23 mph to 20 mph
Results : MS 162, Brooklyn
19
2524
21
24 24.5
20.5
161820222426
MP
H
IS 383Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
AM speeds were reduced 10% from an average of 25 mph to 22.5 mph
PM speeds were reduced 6.3% from an average of 24 mph to 22.5 mph
25
22.524.0
22.5
161820222426
MPH
IS 383Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
Results : IS 383, Brooklyn
20
24
22.5
18.5
24
22.5
19.5
16
18
20
22
24
MP
H
PS 299Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
AM speeds were reduced 14.6% from an average of 24 mph to 20.5 mph
PM speeds were reduced 12.5% from an average of 24 mph to 21 mph
24
20.5
24.0
21.0
16
18
20
22
24
MP
H
PS 299Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
Results : MS 299, Brooklyn
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AM speeds increased by 1.4% from an average of 22 mph to 22.3 mph
PM speeds increased 5.9% from an average of 22 mph to 23.3 mph
22 22.322.0
23.3
1618202224
MP
H
PS 123Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
22 22.5 2222
23.5 23
16
18
20
22
24
MP
H
PS 123Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
Results : PS 123, Brooklyn
22
AM speeds were reduced 4.3% from an average of 23.5 mph to 22.5 mph
PM speeds were reduced 2.2% from an average of 23 mph to 22.5 mph
23.5
22.5
23.0
22.5
22
22.5
23
23.5
MP
H
PS 86Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
23.5
22.5 22.5 23 22.5 22.5
16
18
20
22
24
MP
H
PS 86Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
Results : PS 86, Brooklyn
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AM speeds were reduced 15.1% from an average of 24.5 mph to 20.8 mph
PM speeds were reduced 18.4% from an average of 25.5 mph to 20.8 mph
24.5
20.8
25.5
20.8
161820222426
MP
H
PS 16Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
24.5
21 20.5
25.5
21.520
161820222426
MP
H
PS 16Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
Results : PS 16, Queens
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AM speeds were reduced 9.1% from an average of 22 mph to 20 mph
PM speeds were reduced 5.6% from an average of 21.5 mph to 20.3 mph
22
20.0
21.520.3
16
18
20
22
MPH
PS 69Before and After Speeds
AM BEFORE AM AFTER PM BEFORE PM AFTER
22
20.5
19.5
21.5
19.5
21
16
18
20
22
MP
H
PS 69Change in Speeds over Time
AM BEFORE AM AFTER 1 AM AFTER 2PM BEFORE PM AFTER 1 PM AFTER 2
Results : PS 69, Queens
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Conclusions from Pilot II
Flashing Beacons accompanied by 20 MPH reduced speed limit signs resulted in a reduction of speeds:AM Speeds decreased overall from 23.7 mph to 21.2 mph (a 10% decline) PM Speeds decreased overall from 24.2 mph to 21.1 mph (a 12% decline)
Speeds decreased over time:7.8% after the 1st “after” AM speed test
12.3% after the 2nd “after” AM speed run 9.5% after the 1st “after” PM speed run 12.3% after the 2nd “after” PM speed run
This shows that reduction of speeds can be maintained over several months.
Traffic Control:• On streets with downstream signalized intersections speeds decreased 9.9% and 12.9% in the AM
and PM respectively • On streets with downstream stop controlled intersections speeds decreased and 12.6% in the AM and
PM.
JHS 118 had the largest decline in speed. Speeds decreased 23.2% in the AM and 29.7% in the PM.
PS 123 in Brooklyn was the only school not to show a decrease in speed. Speeds increased slightly from 22.0 mph to 22.3 mph in the AM and from 22.0 mph in the PM to 23.3 mph.