High Risk Rural Roads Program Guideline

Transcription

1 High Risk Rural Roads Program Guideline 3.1 High Risk Rural Roads Program (HRRRP) SFETE-LU introduced a new set-aside provision known as the High Risk Rural Roads Program (HRRRP), codified as 23 U.S.C. 148 (f) for reducing the frequency and severity of collisions on rural roads functionally classified as a rural major collector, rural minor collector and rural local roads by correcting or improving hazardous locations or features. The program is a component of the Highway Safety Improvement Program (HSIP). 23 U.S.C. 148 (a)(1) defines a HRRR according to the following definition: any roadway functionally classified as a rural major or minor collector or rural local road. on which the crash rate for fatalities and incapacitating injuries exceeds the statewide average for those functional classes of roadway; or. that will likely have increases in traffic volume that are likely to create an crash rate for fatalities and incapacitating injuries that exceeds the statewide average for those functional classes of roadway. The Federal Highway dministration (FHW) established the amount of annual funds appointed to the HRRR Program. Virginia has annually appointed approximately $2.0 million and the funding allocated to each of the nine VDOT construction districts based on proportion of severe crashes in three years. For a project to be eligible for HRRRP funds, the project roadways must be functionally classified as a rural major collector, rural minor collector, or rural local roads with fatal and incapacitating injury crash rate above the statewide average for those functional classes of roadways. Projects may be selected on any public HRRRP-eligible roadway in Virginia to correct or improve hazardous road locations or features. HRRRP funds can only be used for construction and operational improvements on high risk rural roads and the planning, preliminary engineering, and Roadway Safety udits (RS) related to specific high risk rural road improvements (HSIP Final Rule 23 CFR part (c)(2), December 24, 2008). VDOT administers the HRRRP centrally with input and concurrence on recommended projects from regional traffic engineering staffs. Funding is allocated to each construction district based on the proportion of fatal and incapacitating 1 injuries (K+). Since VDOT maintains all rural roads (except for Federal Lands facilities), data is available to conduct comprehensive safety planning for the HRRR. 1 Virginia follows the KC Severity scale as K = death, = Visible signs of injury, = Visible but minor injury, C = o visible injury but complaint of pain injury

2 To develop project proposals, consultant services were used to conduct RSs at eligible locations identified by HSIP staff. Submitted proposals for HRRR funding must follow the requirements of HSIP project development. Engineering RS studies of proposed projects, which include the HSIP economic analysis (enefit/cost analysis), are submitted by regional staff for funding. 3.2 Data Description and Identification Procedures Three major elements as crash location, crash severity and vehicle exposure are needed to meet the HRRRP requirement for determining fatal and incapacitating injury (K+) crash rates on eligible locations Virginia Department of Transportation (VDOT) solidly stains detailed records on historical crash, roadway inventory and traffic information in the Highway Traffic Records Information System (HTRIS). The HTRIS is a comprehensive Oracle database and contains multiple subsystems and the subsystems store and access via base or derived relations. For establishing the HRRRP, three subsystems such as ccident (CC): a subsystem which contained crash, vehicle and human information derived from Police Crash Report (FR300), Roadway Inventory (RDI): a subsystem which contained attribute information of highway, roads and street network consisted of over 200,000 segments, and Traffic Monitoring System (TMS): a subsystem which contained travel, demographic, pavement condition, travel activity by vehicle type and continuous traffic data on all public roads. For identifying eligible locations which met the required FHW statutory, VDOT has developed systematic approaches which completely linking and rightly compiling and consolidating the three sub-systems (CC, RDI and TMS) to extract the major elements that needed. set of Structure Query Language (SQL), a standard programming language for retrieving Oracle database, were used to connect the sub-systems and Statistical Package for the Social Sciences (SPSS) was then used to manage the data further to produce statistical test. Data manipulation procedures included screening of eligible locations and identification of safety improvement project locations from the screening are shown in Figure 3-1. Intersection and segment are separately conducted the procedures and specific guidance related to each step is outlined below;

3 FIGURE 3-1. Data Procedures for Identifying/Prioritizing HRRRP Sites Step 1 Roadway Inventory (RDI) Step 2 Intersection (HTRIS ode) Segment (HTRIS Link) Step 3 O SEEIG 1 Eligible configuration of approaches FC? SEEIG 1 Eligible FC on segment? O YES JOI Crash (CC) & Traffic (TMS) Data JOI YES Step 4 Calculate Statewide verage Fat. & Incap. Crash Rate Calculate Statewide verage Fat. & Incap. Crash Rate Step 5 O SEEIG 2 Fat. & Incap. > SW ve.? SEEIG 2 Fat. & Incap. > SW ve.? O YES YES Step 6 Candidate of HRRRP Intersections Candidate of HRRRP Segments Step 7 Safety Improvement Project Selection Safety Improvement Project Selection FC: Road Functional Classification SW: Statewide HRRRP: High Risk Rural Roads Program : Crash Rate Fat. & Incap.: Fatal and Incapacitating Injury Crash [Step 1] [Step 2] [Step 3] Extract Roadway Inventory (RDI) data from HTRIS Classify roadway network data for intersection and segments Screening eligible intersections and roadway segments functionally classified as a rural major or minor collector or rural local roads Intersections are consisted of a junction where more than two roads either meet or cross at grade. Therefore, intersections are practically consisted one or more than one road functional classes according to approach road characteristics. The defined only eligible roads as rural major or minor collector and rural locals are very straight to assort identifying segments but rather ambiguous for intersections. s a result, VDOT defined eligible HRRR

4 intersection by approach configurations. Only intersections which have at least one approach functional classified one of the three roads but must not have a single approach functionally classified as urban. Figure 3-2 shows example combinations of functional configurations on 4-Legs intersections. FIGURE 3-2. VDOT defined Eligible HRRR Intersection Configurations /C C /C /C /C (a) Type I - Eligible (b) Type II - Eligible (c) Type III - ot Eligible (d) Type IV - ot Eligible pproach : Rural Major Collecotr (FC=4), Rural Minor Collector (FC=5), Rural Local (FC=6) pproach : Rural Interstate (FC=1), Rural Principle rterial (FC=2), Rural Minor rterial (FC=3) pproach C: Urban Interstate (FC=), Urban Freeway and Expressway (FC=), Urban Principle rterial (FC=E) Urban Minor rterial (FC=H), Urban Collector (FC=I), Urban Local (FC=J) [Step 4] Calculate Statewide verage Fatal and Incapacitating Crash Rate after joining Crash (CC) and Traffic (TMS) data on the identified eligible HRRR intersections and segments Crash rates were calculated by counting only the fatal and incapacitating injury crashes (K+) at intersection and segments separately using the following crash rate calculation formulas. Homogeneous locations were classified by configuration and traffic control devices, and road functional classifications for intersections and segments respectively. Therefore, statewide average crash rate of intersections and segments in same homogeneous groups were measured and compared with individual locations at each group. i Crash 1,000,000 = Year 365 Enter DT i s Crash 100,000,000 = Year 365 Length Link DT s ij = k = 1 i or sj = k = 1 s In which, i or s = Intersection (i) or Segment (s) Crash Rate

5 ij or sj = verage Intersection (i) or Segment (s) Crash Rate in same homogeneous group j Crash = Fatal and Incapacitating Injury Crash Frequency Only Year = umber of Year DT i or s = verage nnual Daily Traffic (i = intersection and s = segment) = umber of Sites [Step 5] Flagging/identifying only intersections and segments which have fatal and incapacitating crash rate greater than statewide average in same categories of functional classification or geometric characteristics or features i ij or s sj In which, j or s = Intersection (i) or Segment (s) Crash Rate ij or sj = verage Intersection (i) or Segment (s) Crash Rate in same characteristic of homogeneous group j [Step 6] [Step 7] Final Candidate of intersections and segments which satisfying the required FHW statutory and eligible to use the HRRRP funds. Select the HRRRP intersection and segment project locations which provide maximum benefits from safety implementing using HRRRP funds 3.3 Project Selection [Step 7] and RS Review The identification procedures were conducted using three years ( ) of crash, roadway inventory and traffic data. From the identification procedures, approximate 12.4 % (5, 156) and 12.9% (5,552 miles) of intersections and segments were only satisfied the full FHW required statutory from the results(42, 352 and 43,123 miles of eligible intersection and segments) of roadway inventory (RDI) screening in [Step 3]. To maximize benefits from the limited HRRR funds, VDOT has focuses on identification of the most hazardous HRRR intersections and segments which have highly concentrated fatal and incapacitating injury crash and severities HRRR Intersection Project Location Three different thresholds, as shown in below, were used to screen and to identify HRRR intersection project locations:

6 1. Intersections which have fatal & incapacitating crashes >= 5, and fatal & incapacitating injured people >= 5 2. Intersections which have fatal & incapacitating crashes >= 5, and fatal & incapacitating crash percentage >= 40 % of total crashes 3. Intersections with no safety improvement during last 24 or planned for next 12 months 132 intersections were selected for the highest need of detailed assessment to determine possible treatments. VDOT allocated $400,000 for initiating HRRR program consultant lead Roadway Safety ssessments (RSs). Only 71 of the 132 intersections were identified for conducting crash and field RS reviews within the budget. The final 71 intersections were determined using four measures and a combined final rank (FR) method, as shown in below: 1. Fatal and Incapacitating Crash Frequency (CF) 2. Fatal and Incapacitating Crash Rate () 3. Fatal and Incapacitating Severity (People) Frequency (SF) 4. Fatal and Incapacitating Severity (People) Rate (SR) 5. Final Rank ( FR ) = Rank ( CF ) + Rank ( ) + Rank 4 ( SF ) + Rank ( SR ) Table 6-1 provides the distribution of the 71 intersections across Virginia. There are no intersections in orthern Virginia (OV) which is the most urbanized district in Virginia but over 70 percent of the intersections (51 intersections) are located the Salem, Lynchburg, Hampton Roads and Fredericksburg Districts. Table 3-1 Selected High Severe Crash HRRR Intersections District # of Intersections % 1 ristol Salem Lynchburg Richmond Hampton Roads Fredericksburg Culpeper Staunton OV TOTL

7 Roadway Safety ssessments were conducted at those 71 severe crash HRRR intersections. Three different terms of countermeasures for short, intermediate, and longterm have been recommended. Short-term recommendations are projects that can be completed in the immediate future at minimal expense with no right-of-way impacts, essentially maintenance treatments. Intermediate recommendations are those that require preliminary engineering, design, potential right-of-way acquisition and utilities work, and/or minor disturbance to operations. Long-term recommendations are the most expensive solutions that would require extensive design, right-of-way acquisition, utility relocation, and take much longer to plan, design, and reconstruct. lso, all the recommendations were categorized into maintenance, design and operation, and driving behaviors based on driving and crash patterns identified from traffic counts, collision diagrams and field review HRRR Segment Project Location VDOT has focused spending HRRRP funding on segments which have high Roadway Departure (RD) crashes. Segments which have high RD crash frequency were selected and prioritized from the 5,552 miles. There were 10,700 RD crashes which occurred at the 5,552 miles of segments during last 3 years ( ). s you shown in Figure 3-3, there was one spot which have 7 times of RD crashes between 2005 and 2007 but over 98 % of spots had been only one or two RD crashes. On the other words, RD crashes were occurred very randomly and dispersedly (1 spot/3091 ft) distributed. Figure 3-3 Spot Occurred Roadway Departure (RD) Crash Distribution # of RD Crash # of Spot For identifying high RD crash segments, VDOT has developed a search approach named as modified peak search sliding window. This approach fundamentally has same concept of general sliding window technique but multiple windows moved forward and backward inside of boundary which required must include a spot had user-defined RD crash

8 frequency. RD crash density were measured and compared inside of window boundaries as D1, D2 and D3 in Figure 3-4 (a). The identified/determined high RD density segments were combined with adjacent segments when the gap (L) between the identified two or more windows have less than 2500 ft (see Figure 3-4 (b)). s results, four different thresholds, as shown in below, were used to screen and to identify HRRRP segment project locations: 1. Segment must have at least one spot >= 3 RD crash/3year 2. Sliding window length (S) = 1200 ft 3. Consolidating gap (L) = 2500 ft 4. Intersections with no safety improvement during last 24 or planned for next 12 months Figure 3-4 Modified Peak Search Sliding Window D3 D1 D2 High RD Crash Spot Window (S ft) Sliding Windwow (a) Segment Determination L (ft) D i D i (b) Segment Consolidation Table 3-2 provides the distribution of identified about 30 miles of the most critical RD crash segments from the 5,552 miles eligible HRRR segments in statewide. The identified 30 miles of segments have over 30 times higher than statewide average of total and RD crash density respectively.

9 Table 3-2 Selected High RD Crash HRRR Segments District # of Routes Length(Mile) 1 ristol Salem Lynchburg Richmond Hampton Roads Fredericksburg Culpeper Staunton OV TOTL Roadway Safety ssessments (RSs) are currently processing at the 30 miles of high RD crash HRRR segments. RS field review will be conducted for each segment to identify safety issues related to roadway departure and specific strategies included 1. igger and/or brighter chevrons, 2. In-lane pavement markings, 3. Surface friction treatments on curves, 4. Edge line rumble strips. lso, same as intersection RS, three different terms of countermeasures for short-, intermediate-, and long-term will be recommended. 3.4 HRRR Program Implementation Progress HRRRP Funding Set-aside for HRRR projects has been $2 million each year since FY2006. With the 10 percent state match a total of $13.3 million is available for eligible projects. To date there has been no need to supplement the HRRR funds with other sources HRRRP Projects From the HRRR intersection RSs eight projects worth about $1.5 million were programmed in the FY2011 SYIP. dditional projects are pending more detailed engineering studies, such as traffic signal warrant studies, being conducted by VDOT staff. HRRR projects obligations for PE phases before June 2010 are shown in ppendix. ppendix lists the intersection improvement projects.