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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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Suggested Citation:"Chapter 3. Highway Agency Survey Results." National Academies of Sciences, Engineering, and Medicine. 2021. Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Washington, DC: The National Academies Press. doi: 10.17226/26199.
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10 Chapter 3. Highway Agency Survey Results This chapter of the report presents the results of two highway agency surveys, one conducted for this project and one performed for NCHRP Synthesis 417 (30). 3.1 Survey Objectives A survey of state highway agencies was conducted for NCHRP Synthesis 417, Geometric Design Practices for Resurfacing, Restoration, and Rehabilitation (30), and published in 2011. This survey included several key questions concerning state 3R design practices; all 50 states responded to this survey, so the response rate was 100 percent. The survey for NCHRP Synthesis 417 did not include local agencies. The NCHRP Synthesis 417 survey covered many, but not all issues of importance to the current research. Therefore, a survey was conducted as part of the current research to obtain additional relevant information. To minimize duplication of effort, with minor exceptions, the survey conducted in the current research generally avoided asking questions that covered the same material as the survey in NCHRP Synthesis 417. The survey questionnaire used in the current research is presented in Appendix B. The survey for the current research was sent to representatives of the 50 state highway agencies and 235 local agencies. The state highway agency respondents were selected based on membership in the AASHTO Technical Committee on Geometric Design, the AASHTO Subcommittee on Design, or the NCHRP project panel. Potential local agency respondents were based on mailing lists provided by the National Association of County Engineers and the Institute of Transportation Engineers for the related research being conducted in NCHRP Project 15-47, “Developing an Improved Highway Geometric Design Process” (29). The survey was conducted with on-line survey software known as SurveyMonkey. Each potential respondent received an e-mail inviting them to participate in the survey, with a link to the survey questionnaire. 3.2 Survey Response Rate and Type of Respondents A total of 39 responses to the survey were obtained for the survey conducted in the current research. As shown in Table 3, 62 percent of the responses were from state highway agencies and 38 percent were from local highway agencies. The response rate was 48 percent for state highway agencies and 6 percent for local agencies. The low response rate for local agencies suggests that 3R project design is not a key issue at the local level; however, the responses provided are appreciated because previous surveys of this type have not sought input from local agencies.

11 Table 3. Agency Types Represented by Survey Respondents Agency type Number (percent) of responses State highway agency 24 (61.5) Local highway agency 15 (38.5) 39 Source: Based on the survey conducted in the current research. The tables of responses in the remainder of this section combine the information received from the current survey and the NCHRP Synthesis 417 survey. Some tables were based on one survey or the other and some combine information from both surveys; all local highway agency information is from the current survey. Each table includes a note indicating the source of the information presented. There were only minor discrepancies between the results of the NCHRP Synthesis 417 and the survey conducted in the current research; these were investigated and found to result from changed policies between 2011 and 2013. The tables below are based on the latest available information. 3.3 Highway Agency 3R Design Policies and Criteria Table 4 shows that 83 percent of state highway agencies and 47 percent of local highway agencies have specific 3R design policies or criteria. Agencies were asked to provide copies of their 3R design policies or guidelines and any forms they use in documenting 3R design decisions. The 3R design criteria of 10 state highway agencies were reviewed in detail as part of the research (see Section 4.3). Table 4. Agencies with Specific Geometric Design Policies or Criteria for 3R Projects Does your agency have specific geometric design criteria for 3R projects? Number (percent of responses) State agencies Local agencies Total Yes 40 (83.3) 7 (46.7) 47 (74.6) No 8 (16.7) 8 (53.3) 16 (25.4) 48 15 63 Source: Combined data for NCHRP Synthesis 417 and current survey. Table 5 shows that 55 percent of states use the same 3R design policies for projects on the National Highway System (NHS), as well as for non-NHS projects; 87 percent of states use the same 3R design policies for both federal-aid and state-funded projects. The NCHRP Synthesis 417 survey asked agencies that do not have a formal 3R policy why they do not have such a policy. Comments in response to the current survey also addressed this issue. Some highway agencies do not have 3R design criteria because they apply the design criteria for new construction and reconstruction projects to resurfacing projects and seek design exceptions where appropriate.

12 Table 5. 3R Policies for NHS vs. non-NHS Projects and Federal-Aid vs. State-Funded Projects Are 3R policies the same for both types of projects? Number (percent) of respondents from state agencies NHS vs. non-NHS projects Federal-aid vs. state- funded projects Yes 26 (55.3) 41 (87.2) No 21 (16.7) 6 (12.8) 47 47 Source: NCHRP Synthesis 417. Other highway agencies previously had 3R design criteria but have now adopted a design matrix approach that can assign any of several levels of design criteria to specific projects. This approach is discussed in Section 4.3. 3.4 Identification of the Need for 3R Projects Table 6 shows how states initially determine the need for 3R projects. The most common factor is condition of pavement, which was cited by 88 percent of states. Safety analysis was a factor in identifying project need for 20 percent of states. Other factors cited were community requests/public input, needs for widening, and condition of structures (particularly for small bridges and culverts). Table 6. Identification of Need for 3R Projects How are 3R projects initially determined? Number (percent) of Responses from state agencies Condition of pavement 35 (87.5) Safety analysis 8 (20.0) Community request/public input 2 ( 5.0) Need for widening 1 ( 2.5) Structure condition (small bridges and culverts) 1 ( 2.5) Other 1 ( 2.5) NOTE: Based on responses from 40 states in NCHRP Synthesis 417; percentages add to more than 100 percent because of multiple responses. 3.5 Consideration of Crash History in Design of 3R Projects Table 7 shows that 77 percent of state agencies and 82 percent of local agencies consider the crash history of the project site as part of the design of 3R projects. It is notable that, while Table 6 indicates that only 20 percent of states use crash history in identifying the need for a 3R project, Table 7 shows that a majority of states consider crash history in the design of 3R projects.

13 Table 7. Consideration of Crash History in 3R Projects Does your agency’s design process include a review of crash history for every 3R project? Number (percent) of responses State agencies Local agencies Total Yes 36 (76.6) 9 (81.8) 45 (76.6) No 11 (23.4) 2 (18.2) 13 (22.4) 47 11 58 NOTE: Based on the current survey with consideration of a closely related question in the survey for NCHRP Synthesis 417. Table 8 shows that analysis of crash history data is the leading method for consideration of safety in design decisions for 3R projects. Other methods of considering safety included: using Safety Analyst software (which is itself a method of analyzing crash data); conducting site investigations; comparing existing geometrics to established design policies; and evaluating safety when considering design exceptions. Local agencies also indicated that they follow state highway agency procedures and/or county safety plans. Table 8. Methods to Consider Safety in Design Decisions for 3R Projects How does your agency consider safety in design decisions for 3R projects? Number (percent) of responses State agencies Local agencies Total Analyze crash data 16 (94.1) 4 (50.0) 20 (80.0) Use Safety Analyst 1 ( 5.9) 0 ( 0.0) 1 ( 4.0) Conduct site investigation 0 ( 0.0) 1 (12.5) 1 ( 4.0) Compare existing geometrics to established design policies 0 ( 0.0) 1 (12.5) 1 ( 4.0) Evaluate safety when considering design exceptions 1 ( 5.9) 0 ( 0.0) 1 ( 4.0) Follow state highway agency procedures 0 ( 0.0) 2 (25.0) 2 ( 8.0) Follow county safety plan 0 ( 0.0) 1 (12.5) 1 ( 4.0) NOTE: Based on responses to the current survey from 17 state highway agencies and 8 local highway agencies; percentages add to more than 100 percent because of multiple responses. The survey conducted for this research asked respondents an open-ended question about how their agency considers safety in the design of 3R projects. The responses received included: State Agencies  Look at accident history associated with the roadways. We also look at the safety hardware along the roadway, guardrail, traffic signs, and other roadside features.  All 3R projects have a safety element. The mandatory safety improvements are based on the type of 3R project (i.e., freeway, nonfreeway, urban, rural, etc.). We look at the historical crash data for the project section. [NOTE: We are a self-reporting state for crash data. Property-damage-only crashes are notoriously underreported.]  The historical accident data within the project limits of the 3R project will be evaluated. This is typically the most critical element of 3R project evaluation to determine the

14 appropriate level of geometric and safety improvement. Usually, the following accident data analyses are conducted: accident rate versus statewide average; accident analysis by type; accident analysis by location; collision diagrams.  Pavement conditions are considered, crash history is reviewed to identify problem areas to be further reviewed in design, traffic barrier is updated to the latest standards, traffic devices/delineators are updated (signals, striping, signing), existing localized flooding is addressed, sidewalk ramps and crossings are brought up to the latest design standards.  Review crash history. Perform safety assessment and road safety audit (RSA), if applicable. Incorporate low-cost safety items, as applicable. Use HSM to help justify design exceptions/waivers.  Safety is utmost.  Evaluation of accident history and statewide average accident rates on comparable roads are used.  There are many elements of safety that are standard elements incorporated into 3R projects, replacing faded signs, upgrading and/or extending guardrail treatments, and replacing end treatments. Often times, we incorporate slope flattening as part of the 3R project. In past years, budget constraints have limited our ability to fund as many 3R projects as we have in the past. Because of that, slope flattenings may not have been included if there is no crash history in the project limits. In those cases, we try to determine if safety funds are available to flatten slopes.  A traffic accident analysis is generated for every project, and when feasible, those recommendations are implemented. Safety is a strong consideration for 3R projects and measures are incorporated if they are eligible under 3R funding guidelines.  Routinely run crash analysis per project. This is a requirement in our current agreement with FHWA. If there is a known safety issue on a project that is not being addressed it is documented.  Safety data (crash reports/rates, road safety audits) are reviewed as well as relying on nominal safety based on established design criteria (3R policy). Criteria include: roadway geometry, cross section elements (shoulder/lane width/type), horizontal geometrics (superelevation, possible realignment), vertical geometrics (curves/grades), roadside safety (clear zone, side slopes, barrier considerations, drainage structures, sign/light supports, trees, concrete signal bases, curbs, railroad crossings, MUTCD compliant devices, etc.), urban considerations, bridge width/vertical clearance. In recent years, the Highway Safety Manual has been used to evaluate dissimilar alternatives or identify locations where additional improvements may provide a substantive safety benefit.  Our agency does have reduced criteria for some design elements for RRR projects, but strives to meet new construction criteria whenever possible. Whenever criteria cannot be met, a design variation from state criteria, or a design exception from AASHTO criteria is prepared. This documentation requires a safety analysis using the best tool available (HSM, Roadside Safety Analysis Program, historical crash analysis) to quantify the projected costs of crashes vs. the cost of implementing an improvement, usually done on a life-cycle basis.

15  We review all crash data and work with our Safety Office for design recommendations focusing on low-cost elements such as rumble strips, chevrons, widened inside shoulders, etc.  We review crash reports and consult the HSM when making decisions concerning design. Local Agencies  One of the most important aspects of our design decisions. Accident data are reviewed along with site inspections to identify any condition that could be mitigated prior to or during the project.  We look at severity and crash type as well as overall volume of the roadway.  We use our state highway agency’s design manual for 3R criteria.  We follow the guidelines of our state highway agency’s design manual even though we are a local agency. We follow those guidelines for 3R projects, too. The greatest area for concern for 3R projects is usually construction zone traffic control as we are paving or repairing roads or bridges, since we do repairs on roads that are usually still in use while we do the work. Safety is always our first priority. Our inspectors are tasked to review our job sites daily for safety issues.  We review accident reports for our county, which are provided by the state. We can look at 10 years of records. Complaints are also considered, but not given the same weight as accident history. Benefit–cost studies are done on project safety improvements. Not all possible safety improvements are done as many are cost prohibitive. Farm to market funded projects may not have the same level of effort in safety improvements due to tight funding.  The projects are funded by our agency. We rate 3R projects based on shoulder widths, slope flattening, removal of obstructions, and pavement markings, rumble patterns, etc., all with respect to AASHTO design standards.  Wherever practical, depending on the scope of the project.  Consideration of safety is based on our county highway safety plan. Some states are moving away from using formal 3R project criteria. Comments from such agencies included:  Our agency uses a design matrix approach and does not have 3R type projects any longer.  Our Road Design Manual states: “In some cases, preservation projects are projects that safely manage and operate existing systems efficiently while effectively addressing critical safety and operations needs through minor and moderate cost improvements to the existing facility.” “Safety must also be considered in the design of all preservation projects, including cost-effective safety improvements where warranted.” Additionally, safety is considered as part of a Project Safety Review.

16  Up until July 2013, our agency had published 3R design criteria but only a handful of projects ever used them. We now use Safety Analyst for the analysis of crashes for resurfacing and non-resurfacing projects. The issue of highway agencies moving away from use of 3R design criteria is further discussed in Section 4 of this report. 3.6 Inclusion of Safety Improvements in 3R Projects Table 9 shows that 89 percent of states routinely consider safety improvements in 3R projects. The remaining states either do not consider safety improvements unless a safety problem is identified or do not normally consider safety improvements. Table 9. Assessment of How Often Safety Improvements Are Considered in 3R Projects How often are safety improvements considered in 3R projects? Number (percent) of responses from state agencies Routinely considered 41 (89.1) Not considered unless safety problem identified 4 ( 8.7) Not normally considered 1 ( 2.2) 46 NOTE: Based on the survey conducted for NCHRP Synthesis 417. Table 10 shows the types of safety improvements that are most frequently included by states in 3R projects. The safety improvement types cited by more than 20 percent of respondents as being among the five most common types of safety improvements made by their agency in 3R projects included:  Guardrail addition or improvement (including improvement of guardrail end treatments)  Shoulder paving, grading, or widening  Clear zone improvements  Signing improvements  Shoulder or centerline rumble strips  Striping and delineation  Superelevation  Pavement surface condition/friction  Intersection design/turn lanes/turn radius  Roadway/lane widening  Roadside slope flattening

17 Table 10. Most Frequent Safety Improvements Included in 3R Projects Improvement type Number (percent) of responses from state agencies Guardrail addition or improvementa 31 (67.4) Shoulder grading/paving/widening 21 (45.7) Clear zonesb 15 (32.6) Signing 15 (32.6) Shoulder or centerline rumble strips 14 (30.4) Striping and delineation 13 (28.3) Superelevation 13 (28.3) Pavement surface condition friction 12 (26.1) Intersection design/turn lanes/turn radius 11 (23.9) Roadway/lane widening 10 (21.7) Roadside slope flattening 10 (21.7) Horizontal and vertical geometry 9 (19.6) Sight distance 7 (15.2) Pavement edge drop-offs/safety edge 7 (15.2) Culvert extensions 6 (13.0) Bridge rail upgrade 5 (10.0) Pedestrian crossings/sidewalks/curb ramps 5 (10.0) Cross slope improvement 4 ( 8.7) Drainage improvement 4 ( 8.7) Traffic signal improvement 2 ( 4.3) Design speed 2 ( 4.3) Structural improvement 2 ( 4.3) Bridge width 1 ( 2.2) Bicycle facilities 1 ( 2.2) Climbing lanes 1 ( 2.2) Barrier walls 1 ( 2.2) Fencing 1 ( 2.2) Median barrier 1 ( 2.2) Surfaced turnouts for mailboxes 1 ( 2.2) a Also includes improvement of guardrail end treatments. b Includes removing objects, shielding objects, and providing breakaway hardware. NOTE: Compiled from responses to the NCHRP Synthesis 417 survey by 46 state agencies who were asked to identify up to five of their most frequent safety improvements in 3R projects; percentages add to more than 10 percent because of multiple responses. Table 11 shows that 89 percent of states consider pedestrian improvements and 85 percent of states consider bicycle improvements as part of 3R projects.

18 Table 11. Consideration of Pedestrians and Bicyclists in 3R Projects Is consideration given to pedestrians and bicyclists in 3R projects? Number (percent) of respondents from state agencies Consideration of pedestrians Consideration of bicyclists Yes 42 (89.4) 40 (85.1) No 5 (10.6) 7 (14.9) 47 47 NOTE: Based on the survey conducted for NCHRP Synthesis 417. 3.7 Crash Frequency and Severity Measures Used in 3R Project Analyses Table 12 shows the crash frequency, rate, and/or severity measures considered by highway agencies in 3R project analyses. The table shows that a broad variety of measures are used with little consistency between agencies. The survey found that the vast majority of highway agencies consider all crash severity levels in 3R project analyses, with only one or two agencies considering measures such as fatal crashes only, fatal and A-injury crashes, or fatal and all injury crashes. It is likely that highway agencies that consider all crash severity levels place the greatest weight on the most severe crashes. Table 12. Crash Frequency Rate and/or Severity Measures Considered in 3R Project Analyses Crash frequency or severity measure Measure cited by: State agencies Local agencies Crash frequency, last 3 years  Roadway departure crash frequency  Crash frequency by manner of collision  Minimum of five correctable crashes per year  Crash rate  Crash rates, all severity levels  Crash severity distribution  Weighted crash severity distribution/severity index  Crash severity rate  Benefit–cost ratio for countermeasures  No specific measure, just history and public outcry  NOTE: Based on responses to an open-ended question in the survey conducted in the current research. 3.8 Distinction Between Reconstruction and 3R Projects Table 13 shows that 62 percent of responding highway agencies indicated that they do have formal definitions that distinguish between reconstruction and 3R projects, while 38 percent of highway agencies do not have such a definition.

19 Table 13. Formal Definitions That Distinguish Between Reconstruction and 3R Projects Does your agency have formed definitions that distinguish between reconstruction and 3R projects? Number (percent) of responses State agencies Local agencies Total Yes 8 (61.5) 6 (54.5) 14 (58.3) No 5 (38.5) 5 (45.5) 10 (41.7) 13 11 24 NOTE: Based on responses to the survey conducted in the current research. Survey respondents gave the following explanations of how their agency defines the difference between reconstruction and 3R projects: State Agencies  For a project to be classified as reconstruction, the entire structural pavement section must be disturbed/removed and replaced. This includes the pavement and the aggregate base and subbase materials.  Reconstruction projects provide greater roadway width and capacity such as additional lanes and shoulder width to improve mobility, operations, safety, and alter original subgrade. 3R projects are intended to preserve and extend pavement life and enhance safety; widening is limited to less than a full lane.  Reconstruction of an existing highway mainline will typically include the addition of travel lanes and/or reconstruction of the existing horizontal and vertical alignment, but the highway will remain essentially within the existing highway corridor. The primary reason to perform reconstruction of an existing highway is often because the facility cannot accommodate its current or future traffic demands or because the existing alignment is significantly deficient. 3R projects on nonfreeways are primarily intended to extend the service life of the existing facility and to enhance safety.  We define a reconstruction (4R) as much like a 3R, except that 4R allows for the complete reconstruction of the roadway.  Reconstruction is truly “reconstruction” or pavement treatments greater than 6 inches for the purposes of determining whether our 3R criteria apply.  The following definition is taken from our agency’s “Guidance for Preservation....” document. “Reconstruction is not considered a PRR treatment and therefore is not included in these guidelines. Reconstruction typically consists of new pavement structure (pavement, base and subbase), the addition of travel lanes, or extensive changes in horizontal and vertical geometry, typically requiring right-of-way.”  Our agency adheres to FHWA definitions. If 50 percent or more of alignment is altered, RRR criteria are not used.  Typically, a project will be considered reconstruction if the majority (50 percent or more) of the project length involves adding travel lanes, revising the horizontal and/or vertical alignment, widening the roadway, flattening side slopes, or reconstructing the roadway

20 pavement to provide long-term service. While the work is usually confined within the existing highway corridor, some right-of-way acquisition is often required. The primary reasons for reconstructing an existing highway are because the facility cannot accommodate its current or future traffic demands, because the existing alignment or cross section could be improved, and/or because the service life of the pavement has been exceeded. Because of the significant level of work for reconstruction, the design of the project will generally be in accordance with the appropriate new construction criteria based on a 20-year design period, and not considered to be within the scope of this RRR guide. However, some existing cross section elements may be allowed to remain in place.  Our agency’s design manual describes new location and reconstruction (4R) project design criteria. These projects usually represent the highest type design since these are either new roadways or almost totally reconstructed roadway sections. This chapter of the manual is broken into roadway classifications such as urban streets, suburban roadways, two-lane highways, multilane rural highways, and freeways. Our agency’s design manual also describes nonfreeway rehabilitation (3R) project design criteria. Rehabilitation projects are intended to preserve and extend the service life of the existing roadway and to enhance safety. The chapter presents criteria for improvements and enhancements within the context of acceptable rehabilitation project design. The basic purposes of 3R construction projects are to preserve and extend the service life of existing highways and streets and to enhance safety. Because of limited resources, individual rehabilitation projects may have to be limited in scope in an effort to preserve the mobility function of the entire highway system. The scope of 3R projects varies from thin overlays and minor safety upgrading to more complete rehabilitation. 3R projects are those which address pavement needs and/or deficiencies and which substantially follow the existing horizontal and vertical alignment. They differ from reconstruction projects in that reconstruction projects substantially deviate from the existing horizontal and/or vertical alignment and/or add capacity.  Reconstruction involves getting down to the subbase. 3R is focused on surface treatments such as mills, inlays, overlays, nova chip, etc.  A project is considered to be reconstruction when rebuilding portions total 25 percent of the project or more.  3R projects include overlays adding 4 inches or less (typically) of pavement structure (not on the Interstate Highway system). Local Agencies  We use definitions provided within the Local Agency Instructional Memoranda published by our state highway agency. There are design guides which define the difference between 3R work and reconstruction.  If the project proposes to realign the project (horizontal or vertical) for more than 50 percent of its length, it is a reconstruction project. If the project adds additional through lanes it is a reconstruction project as well. Either of these improvements make it a reconstruction project.

21  We use the word “reconditioning” to include resurfacing, rehabilitation or restoration of the pavement structure to extend the life of the roadway and effectively address critical safety and operations needs through minor improvements to the existing facility. Reconditioning projects generally utilize horizontal and vertical alignment but may entail minor widening or geometric improvement. Work may include up to 20 percent curb- and-gutter replacement in urban drainage conditions and does not normally extend beyond the existing ditch bottom for rural design conditions.  Reconstruction involves substantial new pavement areas.  Reconstruction really includes complete reconstruction to eliminate problem geometry, improve drainage, widen roadbed, and provide new pavement structure, etc., 3R primarily replacement of pavement. The survey conducted in the current research also asked respondents how they consider safety in making the decision between implementing a reconstruction project and a 3R project. The responses to these questions are as follows: State Agencies  No formal criterion beyond our standard project scoping process, where a number of factors including safety problems, if any, are considered. The purpose and need statement would include and discuss all such considerations.  The decision is based on engineering judgment.  Our agency has a Safety Priority Index System (SPIS) that ranks problem locations based on crash severity. The two types of projects (reconstruction or safety) are not necessarily tied to each other. A safety project may be considered reconstruction if the safety element, such as a left-turn refuge (for safety reasons). We consider safety projects as a project type. It may be a reconstruction project or we include safety enhancement as part of preservation projects.  The crash history, location and type, are reviewed to determine the needed solution. If there is a solution that can be implemented without reconstruction, it will be considered first. However, if the crash history suggests a solution that is larger than a spot safety improvement, we would consider reconstruction based on the severity and frequency of the crash history.  Safety is utmost.  Projects are identified and selected based on a variety of factors and the magnitude of geometric improvements needed.  Typically, it is the pavement performance that is the driving factor in deciding the need to do a reconstruction project. Having a reconstruction or 3R project in an area might move up a planned safety project in priority in order to combine the two.  Safety measures are implemented in projects when possible.

22  One consideration is available budget and schedule which is influenced by our legislators since they approve our transportation plan. Does not mean that a 3R project can't turn into a reconstruction or vice versa.  Projects are typically selected based on existing roadway/pavement conditions and reviewed for safety elements to determine 1R, 3R, or AASHTO/reconstruction criteria. Factors that may be considered include: scope of the project (resurfacing or pavement replacement), route class, traffic volumes, NHS/non-NHS, historic safety data, etc.  This is done through our agency’s safety office and is almost always on a site-by-site basis (intersections, bad curves, interchange, etc.)  Crashes play a role in determining where we make improvements.  The purpose of the project is the main consideration on whether it is a 4R or 3R project. The safety aspects are included in these decisions.  Our 2R and 3R projects are typically driven by highway condition, not safety.  This decision is based on accident data and condition of the pavement.  Safety is one of the deciding factors in determining the scope of work at nomination time, along with congestion and road condition.  Our Planning Division analyzes the data and makes recommendations.  No formal process. Local Agencies  The impacts of incorporating this must be taken into account (i.e., property impacts).  If the accidents have been caused by a nonstandard roadway feature, such as a curve that is too tight or an intersection that has a misaligned leg, we will do a reconstruction project to make it standard. Our 3R projects seldom address roadway safety issues; the 3R projects typically maintain the existing geometry, grade, width, etc., and simply improve them by maintenance (an asphalt overlay, for example). If there is a roadway safety issue, it usually requires reconstruction of some type.  Funding is so tight, we cannot apply every safety enhancement and still accomplish our goal of improving the road or bridge under the project.  Projects are examined against the following criteria: (a) safety—crash history, (b) age of pavement structure, (c) congestion—existing or forecasted, and (d) facility support of walking, biking and transit. Projects that score strongly go into the reconstruction category and those that do not are put in the 3R category.  The decision is based on crash history.  The decision is based on field review and knowledge of the area. Table 14 shows that all of the states that responded and 75 percent of the local agencies that responded use the same design exception process for both reconstruction and 3R projects. One

23 local agency that does not use the same design exception process for both reconstruction and 3R projects provided the following explanation:  Since the investment in the 3R category is less than the reconstruction investment, and we try to keep to the horizontal and vertical alignments, we have to set a somewhat different standard by nature of the situation. One other local agency commented that they do not have a formal design exception procedure. Table 14. Design Exception Process for Reconstruction and 3R Projects Does your agency use the same design exception process for reconstruction and 3R projects? Number (percent) of responses State agencies Local agencies Total Yes 7 (100.0) 6 (75.0) 13 (86.7) No 0 ( 0.0) 2 (25.0) 2 (13.3) 7 8 15 NOTE: Based on responses to the survey conducted in the current research. 3.9 Use of the Practical Design Concept Table 15 shows that 56 percent of the state and local agencies who responded to the survey use the practical design concept. Respondents were asked an open-ended question to indicate which aspects of practical design they apply to 3R projects, and they responded as follows: State Agencies  We use all aspects of practical design. We typically replace in-kind and make enhancements when practical.  Practical design concepts are applied to all projects regardless of type. They consider selecting a scope of improvements based on the purpose of the project (i.e., surface condition), need for modernization, route continuity, and available funding. Practical improvements may consider geometric and roadside elements, drainage structures, facility type, traffic handling, constructability, and environmental factors.  We use the practical design philosophy on all our projects.  Practical design, design flexibility, and good engineering are always part of every project design, whether the project is considered 3R or reconstruction. Project scope and design features should match the identified need for the project, and applying appropriate design standards should fit in with the project context and scope. Local Agencies  Don't make it perfect; make it safe and workable. This decision also depends on the average daily traffic (ADT) of the road and its regional importance.

24  We always start with the safety aspect. We reach agreement on the necessary safety outcome we seek and once the scope is established to meet the safety outcome we then move into the practical aspects of keeping as much of the infrastructure intact as possible, as long as the infrastructure can remain sound.  The aspects of practical design that we use are feasibility and cost benefit. Table 15. Use of the Practical Design Concept Does your agency use the practical design concept in design of 3R projects? Number (percent) of responses State agencies Local agencies Total Yes 4 (57.1) 5 (55.5) 9 (56.3) No 3 (42.9) 4 (44.5) 7 (43.7) 7 9 16 NOTE: Based on responses to the survey conducted in the current research. Respondents were also asked what practical design guidelines their agency has applied to 3R projects and they responded as follows: State Agencies  Our agreement with FHWA is a time and money savings since we are allowed to replace in-kind and these projects are developed the same way.  As noted above, practical design concepts are applied to all projects regardless of type.  Design guidelines for 3R projects have been developed to allow greater design flexibility. At the district’s option, design values above those presented in this chapter may be used. These guidelines offer sufficient flexibility to ensure cost-effective design and further compliance with the program goals of preserving and extending the service life and enhancing safety. While safety may not be the primary reason for initiating a 3R project, highway safety is an essential element of all projects. These 3R projects are to be developed in a manner which identifies and incorporates appropriate safety enhancements. For the purpose of 3R projects, current ADT volumes of less than 1,500 veh/day are defined as low traffic volume roadways.  Match as-built conditions for 1R and 2R, and as-built to current standards for 3R. Safety considerations range from treating clusters and trends if possible to addressing most deficiencies, depending on the project scope. Local Agencies  Use very durable materials that give us the best bang for the buck, such as rubberized AC or rubberized chip seals overlain by a slurry. These last a long time and resist reflective cracking. We also use other recently-invented materials or methods that help stretch our dollars. These include soil nail launching for slope repair, adding FortaFi to the AC mix to increase asphalt pavement life, etc.

25  We try to keep as much of the core infrastructure as possible so we do limited drainage improvements while keeping line and grade fairly consistent with existing.  We have guidelines for bike lanes and associated city standards. 3.10 Use of TRB Special Report 214 Design Guidelines Table 16 shows the use made by highway agencies of the 3R design guidelines in TRB Special Report 214 (4). There are no states that have formally adopted TRB Special Report 214 as their 3R design policy. However, four states (25 percent of the responding agencies) have formal 3R design guidelines that are identical or nearly identical to TRB Special Report 214. Seven states (44 percent) considered TRB Special Report 214 in development of their 3R design guidelines, but have design guidelines that differ substantially from TRB Special Report 214. Thus, 69 percent of responding states at least consulted TRB Special Report 214 in the formulation of their 3R design guidelines. Five of the responding states (31 percent) do not use TRB Special Report 214. Table 16 shows that the vast majority of local agencies that responded on this issue do not use TRB Special Report 214. Table 16. Highway Agency Use of TRB Special Report 214 Design Guidelines for 3R Projects What use does your agency make of the existing 3R design guidelines recommended in TRB Special Report 214? Number (percent) of responses State agencies Local agencies Total TRB Special Report 214 recommendations serve as our agency’s 3R design policy. 0 ( 0.0) 0 ( 0.0) 0 ( 0.0) Our agency has its own formal 3R design guidelines that are identical or nearly identical to TRB Special Report 214. 4 (25.0) 0 ( 0.0) 4 (16.7) Our agency considered TRB Special Report 214 in development of 3R design guidelines, but our design guidelines differ substantially from TRB Special Report 214. 7 (43.8) 1 (12.5) 8 (33.3) Our agency does not use TRB Special Report 214. 5 (31.3) 6 (75.0) 11 (45.8) Other (please specify). 0 (0.0) 1 (12.5) 1 (4.2) 16 8 24 NOTE: Based on responses to the survey conducted in the current research. The following comments were made by respondents concerning the use of TRB Special Report 214: State Agencies  We no longer have 3R standards derived from TRB Special Report 214.  We are currently developing 3R guidance and are using TRB SR 214 as a basis for our guidance.

26  Our guidelines are based on TRB Special Report 214.  Not sure how our guidance compares. It was developed in the early 1990s and may share some of the same guidance.  Our guidelines have incorporated some portions of TRB Special Report 214. Local Agencies  TRB Special Report 214 was used as reference in our development  We follow our state DOT's 3R policy  We tend to follow our own guidelines 3.11 Use of Analytical Tools in 3R Design Decisions Table 17 shows that 47 percent of the responding states have used analytical tools in design decisions for 3R projects, while 53 percent have not. In most cases, the analytical tool used by states was the AASHTO Highway Safety Manual (6,7), presumably the HSM Part C procedures. Other analytical tools that states indicated they have used included the AASHTOWare Safety Analyst software tools (27,28), the Roadside Safety Analysis Program (RSAP) (12,13,14), and the FHWA Interactive Highway Safety Design Model (IHSDM) (23,24). Table 17 also shows that local agencies are far less likely than state agencies to have used analytical tools in the design of 3R projects. In fact, only 21 percent of local agencies reported using analytical tools for 3R project design decisions, while 79 percent have not. Table 17. Highway Agency Use of Analytical Tools in 3R Design Decisions Has your agency used any of the following analytical tools in design decision for 3R projects? Number (percent) of responses State agencies Local agencies Total AASHTO Highway Safety Manual (HSM) 9 (47.4) 2 (14.3) 11 (33.3) AASHTOWare Safety Analyst software tools 1 ( 5.3) 0 ( 0.0) 1 ( 3.0) Roadside Safety Analysis Program (RSAP) 2 (10.5) 1 ( 7.1) 3 ( 9.1) Resurfacing Safety Resource Allocation Program (RSRAP) 0 ( 0.0) 0 ( 0.0) 0 ( 0.0) Interactive Highway Safety Design Model (IHSDM) 5 (26.3) 0 ( 0.0) 5 (15.2) Other (please specify) 0 ( 0.0) 0 ( 0.0) 0 ( 0.0) None indicated 10 (52.6) 11 (78.7) 21 (63.6) NOTE: Based on 19 responses from state highway agencies and 14 responses from local highway agencies in the survey conducted as part of the current research; percentages sum to more than 100 percent because of multiple responses. 3.12 Need for Benefit–cost Analysis Tools Table 18 shows responses from highway agencies to the question as to whether it would be helpful to have a simple benefit–cost analysis tool, such as a spreadsheet tool, for assessing the

27 benefits and costs of safety improvements in 3R projects. Nearly 90 percent of respondents indicated that such a tool would be helpful. Table 18. Need for Benefit–cost Analysis Tool Would it be helpful to your agency to have a simple benefit–cost analysis tool, such as a spreadsheet-based tool, for assessing the benefits and costs of safety improvements in 3R projects? Number (percent) of responses State agencies Local agencies Total Yes 17 (89.5) 7 (87.5) 24 (88.9) No 2 (10.5) 1 (12.5) 3 (11.1) 19 8 27 NOTE: Based on the survey conducted in the current research.

Next: Chapter 4. Current Highway Agency 3R Design Guidelines »
Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects Get This Book
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The aging U.S. highway system, coupled with fiscal constraints, is placing increased pressures on highway agencies to maintain the highway system in a cost-effective manner and is, thus, creating greater needs for 3R projects.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 244: Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects presents the results of research to develop improved design guidelines for 3R projects. The guidelines were developed to replace the older guidance presented in TRB Special Report 214: Designing Safer Roads: Practices for Resurfacing, Restoration, and Rehabilitation.

Supplementary to the Document is NCHRP Research Report 876: Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Two spreadsheet tools for benefit–cost analysis in support of design decisions for 3R projects also accompany the report. Spreadsheet Tool 1 is a tool for analysis of a single design alternative or combination of alternatives. Spreadsheet Tool 2 is a tool for comparison of several design alternatives or combinations of alternatives.

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