Transcript 2013 Mid-Continent Transportation Research Symposium

2013 Mid-Continent Transportation
Research Symposium
August 15, 2013
Gateway Hotel
Ames, IA
Evaluation of Mitigation for Safety Concerns
on Low Volume, Unpaved Rural Roads in Iowa
Tom McDonald, PE
• Iowa Local Technical Assistance Program
• Iowa State University
• (515) 294-6384
• [email protected]
Background
• Total roads in Iowa
• State
• Counties
• Municipal
~ 114,000 miles
~9,300
~90,000
~15,000
• Paved
~ 42,000
• Unpaved
~ 72,000 (63%)
• Over one-half of all crashes and almost half of fatalities occur on local roads !
2010 Institute for Transportation Research
• Reviewed crash history on 2 lane rural roads in Iowa
• State and local agency
• Paved and unpaved
• For local rural, low volume roads
• Major crash involvement with younger drivers and higher speeds
• In comparing crash performance vs. road characteristics;
• Density, rate, & frequency
• Unpaved roads with traffic volumes of 101-400 vpd identified with poorest
safety performance
More study recommended
2011 – 2012 Research Project
• Crash mitigation on rural, unpaved roads with traffic volume > 100 vpd
• ~ 4400 miles statewide, (average 44 miles/county)
• Select study segments from central Iowa counties
• Use multi-disciplinary approach to address crash history
• Analyze results of mitigation selected.
Crash Maps
LYON
OSCEOLA
DICKINSON
EMMET
WORTH
WINNEBAGO
HOWARD
MITCHELL
WINNESHIEK
ALLAMAKEE
KOSSUTH
SIOUX
OBRIEN
PLYMOUTH
CLAY
CHEROKEE
WOODBURY
PALO ALTO
BUENA VISTA
IDA
HANCOCK
POCAHONTAS
CERRO GORDO
FLOYD
HUMBOLDT
FAYETTE
CLAYTON
BUCHANAN
DELAWARE
BREMER
WRIGHT
FRANKLIN
BUTLER
BLACK HAWK
WEBSTER
SAC
CHICKASAW
CALHOUN
HAMILTON
DUBUQUE
GRUNDY
HARDIN
JACKSON
JONES
MONONA
CRAWFORD
TAMA
CARROLL
GREENE
BOONE
STORY
STORY
(2)
LINN
BENTON
MARSHALL
CLINTON
CEDAR
HARRISON
SHELBY
AUDUBON
GUTHRIE
DALLAS
DALLAS
POLK
JASPER
JASPER
IOWA
POWESHIEK
JOHNSON
SCOTT
MUSCATINE
POTTAWATTAMIE
CASS
ADAIR
MADISON
WARREN
(2)
MARION
KEOKUK
MAHASKA
WASHINGTON
LOUISA
MILLS
FREMONT
MONTGOMERY
PAGE
ADAMS
TAYLOR
UNION
RINGGOLD
CLARKE
DECATUR
LUCAS
WAYNE
MONROE
APPANOOSE
WAPELLO
DAVIS
JEFFERSON
HENRY
VAN BUREN
LEE
DES MOINES
Selected Study Segments
Summary of Low Volume Road Segments
2001-2010 Data
County
Segment
Length
ADT
*Crashes
PDOs
Density
Rate
Severity
$ Loss
Story
“
550th Ave.
Grant Ave.
1.99
2.45
110
222
18
29
11
17
0.9
1.02
2253
1461
22,148
3,813
200,337
44,503
“
Madison
19th Street
Holliwell
2.76
1.68
202
260
14
11
10
9
0.51
0.65
688
690
4,143
885
21,014
5,792
Jasper
N. 39th Ave.
2.95
201
12
6
0.41
554
1,960
7,981
“
W. 4th St. S
1.44
206
15
7
1.11
1385
3,206
66,985
“
E. 5th St. S
1.43
280
14
5
0.63
958
3,568
34,930
Warren
150th Ave.
2.05
281
24
6
0.93
1141
3,030
35,456
“
“
118th Ave.
Nevada St.
2.75
3.27
313
246
16
7
8
2
0.58
0.21
509
238
1,385
2,191
8,058
4,691
130th St.
Bittersweet
Old Portland
Smith Ave.
Marsh Ave.
2.79
4.67
3.38
3.5
2.25
173
115
203
171
150
15
11
7
16
9
9
4
5
10
3
0.39
0.23
0.21
0.46
0.4
851
561
280
732
731
26,069
2,735
1,236
1,538
2,268
140,054
6,314
2,558
7,029
9,071
Dallas
“
“
Marshall
“
CR = N / [A x Y x 365 x L] x 100,000,000
Compile Segment Data
Story County, 530th (Grant) from NCL of Ames to SCL of Gilbert, 2.45 mi.
Crash history, 2001 through 2010 (10 years)
29 total crashes, 21 injuries, no fatalities
1 animal
1 ran Stop sign
3 FTYROR (from Stop sign and from uncontrolled intersection)
15 speed related
4 ROR
No adverse surface conditions reported
40 total drivers
22 teenage (55%)
1 +65
1 impaired driver
Objects struck
12 ditch/embankment
Hours of day for crashes
5 from 6:00 through 8:00, 17%
18 from 14:00 through 20:00, 62%
Next Steps
• Meet with local agency officials in counties with selected
segments
– Determine interest in participating in study
– Review crash history and recent safety enhancements
• Engineering, law enforcement, educational efforts
– Invite on field review of current conditions
– Suggest and select appropriate mitigation
• Engineering, law enforcement, school, and media
– Meet with others with potential interest
• Near-by school officials and driver instructors
Field Reviews
• Note higher crash locations, actual and potential
• Perform speed evaluations
• Record conditions on images
• Measure roadway width, document surface and geometric
conditions
Speed Evaluations
Sequential Detail Report
HI-Star ID: 7552
Begin: Dec/08/11 14:00
Street: 130th St
State: IA
City:
End:
Hours:
96.00
Oper: OOS
Period:
Sequential
Posted: 55
County: Dallas
Dec/12/11 14:00
Lane: EB
Raw Count:
AADT Factor: 1
AADT Count:
239
60
Gap Time
Count
Date / Time
Advice
Speed
Length
in
Headway
Seconds
in Feet
Tail Gating
1
2011/12/08 14:09:33.00
Normal
51 MPH
23.00 FT
0
0 No
2
2011/12/08 14:35:03.00
Exceeded Maximum Length
30 MPH
14.00 FT
0
1 Yes
[ Thursday, December 08, 2011 14:00 - 15:00 ]
Raw Count:
2
Average Speed:
Classified Count:
2
Average Length:
40 MPH
18.00 F
T
0
Occupancy:
Average Headway:
Average Gap:
0
Tailgating Count:
3
2011/12/08 15:13:08.00
Normal
55 MPH
12.00 FT
0
2 Yes
4
2011/12/08 15:17:33.00
Normal
52 MPH
18.00 FT
0
0 Yes
5
2011/12/08 15:21:22.00
Normal
44 MPH
16.00 FT
0
0 Yes
6
2011/12/08 15:30:06.00
Averaged Speed Only
47 MPH
32.00 FT
0
0 Yes
7
2011/12/08 15:35:15.00
Exceeded Maximum Length
51 MPH
14.00 FT
0
0 Yes
8
2011/12/08 15:42:40.00
Normal
73 MPH
21.00 FT
0
1 Yes
9
2011/12/08 15:47:19.00
Normal
63 MPH
12.00 FT
0
0 Yes
10
2011/12/08 15:51:17.00
Normal
60 MPH
19.00 FT
0
0 Yes
11
2011/12/08 15:53:48.00
Normal
34 MPH
8.00 FT
0
0 Yes
12
2011/12/08 15:56:47.00
Normal
56 MPH
25.00 FT
0
0 Yes
0.03 %
1
Speeding violations by Day
130th Street Dallas County
W B
Use to Select
Enforcement
E B
(>55)
(>65)
(>55)
(>65)
Sunday
19
5
8
2
Monday
8
3
7
3
AM Count Only
Thursday
9
6
11
3
PM Count Only
Friday
15
6
10
3
Saturday
14
7
7
3
Total
65
27
43
14
Periods
Count
% Violations.
301
22%
# of Violations
Total Traffic Counted
239
9%
18%
6%
Possible Mitigation Considered
•
Engineering Options:
-
•
Law enforcement Options:
-
•
Upgrade existing signing
Install delineators with appropriate colors on both sides
Remove or relocate roadside obstacles
Remove or trim existing vegetation in clear zone
Periodic patrols at high crash/violation times
Monitor speeds with recording devices
Monitor seat belt use
Occasional visits with driver instructors in high schools where appropriate
Educational Options
-
Article in local newspaper occasionally (annual?)
Annual presentation to new drivers in high school drivers ed. classes
o Engineer, law enforcement, or LTAP
Examples of Mitigation Applied
Potential Mitigation Strategies
County
Route
Mitigation Strategy
Dallas
130th Street
Jasper
E 5th St. S
X
Remove Vegetation
X
X
X
X
X
X
Warren
150th Avenue
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Review Crash Clusters
X
TCD - Flags, Chevron & Cross Traffic
X
X
X
X
News Media Release
Meet w/High School Officials
Story
550th Avenue
X
Reduce Speed Limit
Additional Enforcement
Story
530th Avenue
Proposed Employed Proposed Employed Proposed Employed Proposed Employed Proposed Employed Proposed Employed
Highly Reflective Signs
Add Delineators
Jasper
W 4th St. S
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Engineering Strategies
Law Enforcement
Documentation of Enhanced Law Enforcement Activities
LVSR II Project March - May 2013
Date
3/15/2013
3/18/2013
3/24/2013
4/6/2013
4/12/2013
4/14/2013
4/25/2013
4/29/2013
5/10/2013
5/12/2013
Date
3/16/2013
3/21/2013
3/29/2013
4/4/2013
4/8/2013
4/20/2013
4/26/2013
4/28/2013
5/8/2013
Agency- Story County Sheriff's Office
530th (Grant) Avenue
Time Spent
Time Stationary (S) Number Vehicles Improper Citations
Start
Stop
(Hrs) Mobile (M)
Encountered Actions Noted Issued
7 am
9 am
2
S
13
2
0
7 am
9 am
2
S+M
4
2
1
3 pm
5 pm
2
S
16
1
0
1 pm
3 pm
2
S+M
22
0
0
3 pm
5 pm
2
S
35
0
0
1 pm
3 pm
2
S+M
18
0
0
3 pm
5 pm
2
S
67
0
0
7 am
9 am
2
S+M
13
2
0
3 pm
5 pm
2
S
19
2
2
1:30 pm 3:30 pm 2
S+M
13
0
0
Time
Start
3 pm
3 pm
3 pm
3 pm
7 am
7 am
1 pm
3 pm
7 am
Spent
Stop
5 pm
5 pm
5 pm
5 pm
9 am
9 am
3 pm
5 pm
9 am
550th Avenue
Time Stationary (S) Number Vehicles Improper Citations
(Hrs) Mobile (M)
Encountered Actions Noted Issued
2
S+M
6
2
0
2
S
22
0
0
2
S
14
0
0
2
S
12
0
0
2
S+M
15
2
1
2
S
5
0
0
2
S
3
0
0
2
S
11
0
0
2
S+M
8
0
0
News Release
News Release
In December of 2010, Iowa State University released a study titled “Safety Analysis of Low Volume Rural Roads in Iowa”. Several conclusions in that
report emphasized the much higher crash rates and densities for many types of the crash events taking place on unpaved rural roads with traffic
counts between 100 and 400 vehicles per day. Using the information gleaned from that investigation and report, a follow up study was begun in the
fall of 2011 to review some typical area roads that fall in that category. Field reviews of several road segments in Story and nearby counties were
conducted, possible crash causes noted and suggestions made for possible physical improvements made to clear delineate the roadside, if
appropriate. A second phase of this study is to attempt to find possible other mitigation strategies that could possibly be used to reduce those high
crash rates noted.
Two short road segments in Story County were originally identified as study sites, and after conducting field reviews and speed studies and also
holding discussions with local engineering and law enforcement officials, two strategies have been now been chosen to be employed. First, all
existing signs along the routes will be replaced with ones of higher reflective value and secondly, additional enforcement will be employed for a
period of time to hopefully slow traffic and also to help identify typical driver traits and actions that might account for the higher crash numbers that
have been recorded rates noted. The Story County Sheriff’s Office will be begin conducting that additional enforcement this Friday and it will be
continued for approximately two months.
An analysis of before and after crash data is planned, but only after the improvements and enforcement have been in place for a two to three years.
The original safety analysis report may be viewed on the Institute for Transportation website at
http://www.intrans.iastate.edu/reports/souleyrette_low_vol_report_w_cvr.pdf
Meeting with High School Officials
• Principal, driver educator, school bus supervisor
• County engineer and deputy, Governors Traffic Safety
Bureau, LTAP researchers
• Shared general data from school district crashes &
specific information about study segment
• Discussed on-going and future plans of school district for
addressing student driver safety
Findings
• When high school was in close proximity, student drivers are
involved in crashes to a significant extent
• Speed also a major contributor to many crashes
• Identifying other reliable contributors difficult on these roads
• Multi-disciplinary approach to crash mitigation can be
effective
• Larger study sample across state may yield differing results
• Insufficient time with this study to fully evaluate results
Volume vs. Frequency ??
35
30
25
20
15
10
5
0
110
115
150
171
173
201
202
203
206
222
246
260
280
281
313
35
30
25
crashes
20
15
10
5
0
0
50
100
150
200
Traffic Volumes
250
300
350
Recommendations
• Undertake expanded study to consider more samples across a broader
area of the state
• Promote study for reducing statutory 55 mph speed limit on unpaved
roads, statewide or on higher crash segments
• Post regulatory speed limit intermittently on unpaved roads with higher
crash frequencies
• Include mandatory minimum experience and instruction for operating a
motor vehicle on unpaved roads in new driver training
• Take advantage of multi-disciplinary opportunities to address crashes on
unpaved rural roads
Questions