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 tmcdonal@iastate.edu

Background Total roads in Iowa ~ 114,000 miles Paved ~ 42,000 State ~9,300 Counties ~90,000 Municipal ~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

Selected Study Segments

Compile Segment Data

Crash history, 2001 through 2010 (10 years) 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 News media

Field Reviews Note higher crash locations, actual and potential Perform speed evaluations Record conditions on images Measure roadway width, document surface and geometric conditions

Sequential Detail Report Speed Evaluations Sequential Detail Report HI-Star ID: 7552 Begin: Dec/08/11 14:00 End: Dec/12/11 14:00 Street: 130th St Lane: EB Hours: 96.00 State: IA Oper: OOS Period: Sequential City: Posted: 55 Raw Count: 239 County: Dallas AADT Factor: 1 AADT Count: 60 Gap Time in Headway Count Date / Time Advice Speed Length Seconds in Feet Tail Gating 2011/12/08 14:09:33.00 Normal 51 MPH 23.00 FT No 2 2011/12/08 14:35:03.00 Exceeded Maximum Length 30 14.00 Yes [ Thursday, December 08, 2011 14:00 - 15:00 ] Average Speed: 40 Average Gap: Occupancy: 0.03 % Classified Count: Average Length: 18.00 Average Headway: Tailgating Count: 3 2011/12/08 15:13:08.00 12.00 4 2011/12/08 15:17:33.00 52 5 2011/12/08 15:21:22.00 44 16.00 6 2011/12/08 15:30:06.00 Averaged Speed Only 47 32.00 7 2011/12/08 15:35:15.00 8 2011/12/08 15:42:40.00 73 21.00 9 2011/12/08 15:47:19.00 63 10 2011/12/08 15:51:17.00 19.00 11 2011/12/08 15:53:48.00 34 8.00 12 2011/12/08 15:56:47.00 56 25.00

Speeding violations by Day   Speeding violations by Day 130th Street Dallas County W B E (>55) (>65) Sunday 19 5 8 2 Monday 3 7 AM Count Only Thursday 9 6 11 PM Count Only Friday 15 10 Saturday 14 Total 65 27 43 # of Violations Count 301 239 Total Traffic Counted % Violations. 22% 9% 18% 6% Use to Select Enforcement Periods

Possible Mitigation Considered Engineering 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 Law enforcement Options: 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 Engineer, law enforcement, or LTAP

Examples of Mitigation Applied

Engineering Strategies

Law Enforcement

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 ??

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