Now Let s Think Systemic

Transcription

1 Now Let s Think Systemic Remote Rural County Use of the Highway Safety Improvement Program TRINITY COUNTY DEPARTMENT OF TRANSPORTATION Richard Tippett Director MEET TRINITY COUNTY 3,208 square miles 13,786 population Elevation ranges >1,000 to 9,025 ft. 692 Miles of County Maintain Roads Trinity River within the National Wild & Scenic River System 3 national forests 3 rd largest lake in California 3 wilderness areas Trinity Alps Part of the Emerald Triangle (dude) NO: Traffic Signals Freeways Parking Meters Incorporated Cities

2 THE CHALLENGE TRINITY COUNTY Small Rural Mountainous Isolated With a perimeter roughly the same as Vermont s, if we flattened the landscape, we d be about the size of Texas. Demographics That a single accident can greatly effect your accident rate

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5 Problems Encountered With Rural Living Forget about a pin map, density of accidents is just too low. With low volume, you can have the highest rates in the state. Significant underreporting of accidents Folks just take care of it. You know where the problems are (usually damaged trees, bent object markers, MBGR or skid marks that terminate at the edge of the dropoff), but the accident data doesn t reflect for feeling/observation A few accidents can alter the results and misdirect. Hard to focus on specifics easy to become political. The Past vs. Now OLD WAY Work Type and Safety Index Not always analytical Political based usually on spectacular accidents Larger projects that involved long lead time items such as right of way. Mistake of submitting a project too small NEW WAY B/C Systemic Needs to carry it s weight (B/C) of 3.5

6 FIRST REACTION HATED IT BIG TIME (and a few other choice words) Without understanding systemic, didn t understand process. Didn t really know how to formulate a good application. County has very high accident rate, and should qualify easy, but was still stuck on work type, which plays poorly with B/C. We don t have hot spots. Still focused on the big fixes in small areas Needed a whole new way of thinking Which doesn t play well in Trinity Now let s think Systemic Thanks to Ted and Jessie The systemic approach is that decision making process does not just identify the most appropriate countermeasure for each individual location, as done when addressing hot spots. Instead, the systemic approach considers multiple locations with similar risk characteristics, selecting the preferred countermeasure(s) appropriate and affordable for widespread implementation. Because countermeasures are intended to be widely implemented, it is necessary to identify low cost solutions.

7 Systemic versus Hot Spot Treatments Improvement Type Hot Spot Systemic Guard Rail Road Widening Median Barriers Traffic Control (signals, roundabouts, etc.) Curve Correction Interchanges Rumble Strips Striping Pedestrian Countdown Heads Curve Warning Signs Access Management Curb Extensions Traffic Calming Systemic analysis favors rural areas (historic hot spot analysis favored urban, high volume, high crash locations) High Cost Low Sample Systemic Countermeasures Countermeasure or Strategy Applicable Crash Types and Primary Contributing Factors Estimated Crash Reduction Install Centerline Striping Head-On, Roadway Departure, Sideswipe 19% - 55% Install Edgeline Striping Roadway Departure 7% Install Centerline Rumble Strips or Head-On, Roadway Departure, Stripes Sideswipe 9% - 37% Install Shoulder Rumble Strips or Stripes Roadway Departure 15% - 45% Install Curve Warning and/or Curve-related, Roadway Advisory Speed Signs Departure, Improper Turning 18% - 35% Install Chevrons Curve-Related, Roadway Departure, Improper Tuning 4% - 60% Install Dynamic Speed Feedback Signs All, Unsafe Speed 7% Improve Sight Distance at Intersections and Driveways All 11% - 56% Install Guardrail Roadway Departure 7% - 47% Widen Shoulders Roadway Departure, Head-On, Sideswipe 3% - 33% Remove Roadside Objects All 22% - 44% Improve Visibility of Pavement Markings and Signs All 7% - 30% Install Intersection Lighting Nighttime (all crash types) 12% - 50% Install High-Friction Surface Treatment Roadway Departure, Wet Road 24% - 50%

8 Cycle Project Descriptions $ Requested $ Awarded 1 1 BridgeRail replacement on 9 Mile Bridge $ 824,421 $ BridgeRail replacement on 9 Mile Bridge 2 Guard Rail at spot location on Ruth Zenia Road 1 Guard Rail at spot location on Trinity Dam Blvd 2 Icy signs at spot location on Trinity Dam Blvd 3 Purchase Accident Software 4 Guard Rail at spot location on Van Duzen Road 5 Guard Rail at spot location on Mad River Road 6 Guard Rail at spot location on Trinity Dam Blvd 1 Guard Rail at spot location on Steiner Flat Road 2 Curve improvement project on Oregon Street $ 957,878 $ 133,500 $ 714,765 $ 163,100 $ 0 $ 0 5 No projects submitted $ 0 $ Systemic re striping project on various roads 2 Systemic re striping project on various roads 3 Systemic warning sign upgrades on various roads $ 3,708,100 $ 3,708, Roundabout at Lance Gulch Road and Hwy 299 $ 1,159,500 $ 1,159,500 8 Trinity County HSIP History 1 Systemic High Friction Surface Treatments on Rush Creek Road 2 Upgrade substandard guardrail at multiple locations $ 2,128,900 $ 2,128,900 Trinity County Crash Trends Very few fatal and severe injury Overrepresentation of Roadway Departure Crashes (typical for rural roadways) Top three contributing factors: Improper turning, Speeding, DUI

9 Identifying Potential Countermeasures CA MUTCD Compliance Crash Trends Signing Striping Traffic Control Roadway Characteristics Clusters of crashes Crash types (roadway departure, head on, turning, etc.) Crash location (curves, intersections, etc.) Driver behavior (speeding, distraction, DUI, etc.) Potential Safety Improvements Lane width Shoulder type & width Median type & width Pavement condition Existing striping Example Striping Improvement Decision Matrix Pavement Width a, b 18 feet 19 feet 20 feet feet 24 feet 25+ feet Centerline Striping Only If head-on or sideswipe crashes: Centerline Rumble Strips Only If head-on or sideswipe crashes but no fixed-object or overturning crashes: Centerline Rumble Strips Only If head-on or sideswipe crashes: Centerline Rumble Strips and Edgeline Striping If head-on or sideswipe crashes but no fixedobject or overturning: Centerline Rumble Strips and Edgeline Striping If head-on or sideswipe crashes AND fixedobject or overturning, crashes: Centerline Rumble Strips and Edgeline Rumble Strips If no head-on or sideswipe crashes: Centerline Striping Only Otherwise: Centerline and Edgeline Striping Otherwise: Centerline and Edgeline Striping If fixed-object or overturning crashes but no head-on or sideswipe crashes: Centerline Striping and Edgeline Rumble Strips If head-on or sideswipe crashes but no fixedobject or overturning crashes: Centerline Rumble Strips and Edgeline Striping Otherwise: Centerline and Edgeline Striping If fixed-object or overturning crashes but no head-on or sideswipe crashes: Centerline Striping and Edgeline Rumble Strips Otherwise: Centerline and Edgeline Striping a According to the California MUTCD, centerline striping is not recommended on roadways less than 18 feet wide. However, edgeline striping is recommended wherever possible. b Assumes the following striping widths: passing centerline (4 ), no-passing centerline (12 ), edgeline (4 ), centerline rumble strip and striping (16 ), edgeline rumble strip and striping (20 ).

10 Example Corridor Rush Creek Road Rush Creek Road Crash Types 7.7% 23.1% Fixed Object Overturning Broadside 69.2% Recommended Improvement Quantity (Lane Miles) Install centerline rumble strips 8.02 Install Shoulder rumble strips 8.39 Restripe the existing passing centerlines with durable no-passing 8.97 centerlines Restripe the existing edgeline with durable striping 9.19 Total Corridor 9.19 Annual (Life Cycle) Benefits $37,982 ($269,978) $29,801 ($211,825) $95,583 ($679,405) $0 ($0) $163,366 ($1,161,209) Initial (Life Cycle) Costs $17,443 ($42,691) $28,793 ($70,471) $87,411 ($213,937) $89,555 ($219,184) $223,203 ($546,285) Life Cycle B/C Ratio Systemic Analysis & HSIP Funding Applying treatments systemically can reduce the risk for crashes where they have yet to occur Systemic crash trend evaluations can identify additional projects and potential countermeasures to make use of existing and future funding sources Trends analysis, locations, countermeasures, and benefit cost results can feed into current and future HSIP applications

11 WHY IS THAT SO IMPORTANT Trends analysis, locations, countermeasures, and benefit cost results can feed into current and future HSIP applications THIS IS WHAT THE SSAPR PROGRAM IS ALL ABOUT SSARP SYSTEMIC SAFETY ANALYSIS REPORT PROGRAM