CHAPTER 4 Conclusions and Suggested Research

4.1 Conclusions

The research team evaluated the information collected during the project, including comments from the TRB project panel on the literature review, the nationwide surveys, and the case studies. It was found that RVAM is an integral part of state DOTs’ yearly goals and is integrated into all aspects of state DOT roadside management. Despite this being stated by the majority of state DOTs interviewed and surveyed, funding is not guaranteed. This discrepancy between priorities and funding is due, in part, to TAMP requirements that state DOTs spend a large portion of funding developing and purchasing tools and technology to assess and maintain structural assets, such as bridges and pavement. Multiple suggestions have been identified for state DOTs to access the necessary funding for RVAM, including future studies and items that state DOTs can accomplish independently. These recommendations are listed below, and the Guidebook goes into further detail on these. The Implementation Plan that was developed for this project provides initial talking points for state DOTs that are beginning the journey of developing their RVAM plan.

4.2 Tools and Technology

Each state DOT interviewed showcased different software and hardware systems. Often, these systems were incapable of communicating with each other, resulting in DOT staff manually moving information from one system to another. In some cases, contractors delivered the information, and in other cases, local DOT field staff completed data collection. The initial information was either handwritten on paper and then transferred to software to include in the state DOT’s database or initially collected via software/hardware and sent through an intermediary software to be converted to a file for analysis. State DOT staff highlighted the importance of new and upcoming software being able to communicate with existing systems.

Many state DOTs are unaware of precise ROW boundaries across large swaths of their state, and several respondents voiced concerns over this lack of knowledge. This issue is primarily for ROW depth, as many DOT staff are unaware how far back land that is owned and maintained by the state DOT extends from the pavement. According to respondents, the ROW width varies from five feet to over a hundred feet, depending on the region of the state, how the original road was developed, and whether the ROW is a state-maintained county road or an interstate, among other factors. This knowledge deficit means some state DOTs are unaware of how much acreage local staff mow or treat annually, which can cause issues when developing work plans or determining budgets for the year.

It is common practice for state DOTs to use Global Positioning Systems/Automatic Vehicle Locator (GPS/AVL) systems in their trucks, particularly for snow and ice removal. Many of the state DOTs interviewed have not installed these devices in any other equipment, such as mowers and tractors, and instead rely on paper maps or staff to record daily workload information on day cards or through workload management systems. TDOT is preparing to install GPS units in mowers and tractors through a statewide contract to enable the central office to see the acreage being mowed each year; this will also provide insight into how much land TDOT currently maintains annually. This will help bridge the knowledge gap between central office and local staff regarding field staff workload.

As state DOTs begin using tools and technology more frequently, the importance of the IT department increases. State DOTs with dedicated IT staff for roadside maintenance/operations stated they are able to update their software as needed, enabling increased software use across their organization. The increased usage can help the central office see the benefits of using tools and technology and will enable state DOTs to identify cost-saving measures, further supporting implementation. State DOTs that do not have dedicated IT or GIS staff stated that they have issues maintaining their systems to ensure they are technologically up to date and that all relevant data is included within the system. If the tools and technology are outdated, local staff may lack access or the inclination to use the tools and technology, which can cause the central office to move away from upgrading these systems due to complaints or a lack of use.

4.3 Terminology

The differences in terminology were evident throughout the project. The research team compiled a list of the commonly used terms for RVAM activities in the Guidebook.

Throughout the surveys and case studies, state DOTs expressed that the definitions provided within the project did not match the definitions used by their organizations. In some cases, this caused state DOTs and utilities to answer questions with incorrect information, as they excluded items to remain consistent with their organizations’ definitions.

During the interviews, it was noted that state DOTs had an easier time advancing RVAM goals when the RVAM and structural assets terms were similar. Multiple state DOTs expressed that they had independently decided to utilize the same terminology, and, in some instances, software programs to track vegetation assets and RVAM activities to help local staff transition. ODOT stated that including maintenance personnel from the central office when determining goals and developing software helped increase staff acceptance of changes related to asset management. Maintenance staff assisted the program administrators in developing guidelines, standard operating procedures, and other high-level organizational planning services. Upper management and the data governance team then approved IT updates that the Transportation Asset Management (TAM) Audit Group developed. Including central office maintenance staff also ensured that the systems developed were compatible with maintenance operations.

4.4 Staffing

Many state agencies have a limited number of staff positions and identified employee retention as an issue within the survey and the case studies. As state DOTs cannot exceed certain numbers of positions within the organization, when a department requires additional staff, positions must be moved from a different department, or the work must be added to an existing position. This can affect the number of IT or GIS staff available when a state DOT implements new tools or technology. If no state DOT staff member has experience with the new tools and technology and a position cannot be created, this can lead the state DOT to avoid using the new system or underutilizing the newly adapted tools and technology.

Adding responsibilities to staff with experience or familiarity with tools and technology was seen throughout the case studies, with three out of the five state DOTs interviewed stating they had one staff member who took on the majority of mapping and tracking of RVAM activities and sites within the state as they had the most prior experience with these systems. For each of the three individuals, this work was in addition to their listed job duties at the time of their hiring. The remaining two state DOTs added mapping and tracking of RVAM activities to existing GIS and IT staff workloads.

It was also noted that staff tend to seek positions with higher pay within a state DOT when their skill set qualifies them for a different job. When experienced staff accept different positions, state DOTs can have a disproportionate number of early career employees comprising local field staff positions. As these staff gain knowledge and experience, they can move up within the organization, creating a knowledge gap as experienced staff leave field positions. State DOTs that do not regularly use tools and technology along the ROW stated most knowledge transfer occurs between staff members. This can lead to a dearth of local knowledge on the ground with large amounts of staff turnover, which can in turn necessitate additional training or changes in how assets are managed year by year. WSDOT stated that when the state DOT added technology and ensured that local field staff were included in the decision-making process, the accountability and ownership of projects increased among local field staff. This in turn contributed positively to staff retention rates as staff felt a stronger connection to their overall work.

During the survey and the case studies, it was noted that including additional tools and technology did not usually reduce the number of hours staff spent on RVAM work. The research team followed up on this through the case studies. Staff interviewed stated this was because local staff know where the assets are located across the ROW, and the additional technology allowed field staff to show central office the amount of work being completed on an annual basis. The hours spent mapping along the ROW were transferred to GIS staff to complete mapping and analysis in the office. So, while this does not currently reduce the number of hours for trained staff, including this information can facilitate quicker training in the future and reduce the time staff spend on the roadside.

4.5 Funding

While state DOT maintenance divisions are looking to enhance RVAM activities, there are issues with acquiring funding. RVAM is often a low funding priority due to federal and state requirements/guidance, a lack of standard terminology, low staff retention, limited access to tools and technology, and limited training for tools and technology. State DOTs have approached these items in different ways; some state DOTs choose to complete the majority of RVAM work in-house while others have opted to contract out the majority of RVAM work. For those state DOTs that have chosen to contract out a large amount of work, state legislators often become less willing to provide the equipment and staffing for RVAM. This can lead to issues where staffing and/or equipment might not be available when staff need to complete reactive RVAM activities, such as maintaining sight distance or ensuring culverts are clear of debris. In addition, if the staff do have time and access to the appropriate equipment, they may not be proficient with the task, possibly leading to errors and deficiencies in the completed work.

As funding for RVAM primarily covers staff salaries, it can be difficult for state DOTs to separate costs associated with RVAM from other activities that may be more high profile. This is further complicated by the fact that RVAM activities are typically not tracked as well as activities included in state TAMPs, which must comply with federal and state requirements. These items can make it more difficult to demonstrate the need for additional funding or equipment. State DOTs that are able to easily retrieve information on RVAM activity costs are able to request additional funding more efficiently.

4.6 Proposed Recommendations

The information collected throughout the study led to multiple recommendations. Some of the recommendations within this report can be completed short-term while others will require multiple years for implementation. Some recommendations are designed for state DOTs while others are meant for federal guidance. The Guidebook goes into further detail on the implementation and recommendations for state DOTs. Each state DOT will need to develop an individualized RVAM plan that takes into account the goals, needs, and capabilities of each state. All recommendations within this section have been approved by the NCHRP panel, NCHRP staff, and the research team.

Tools and Technology

It is recommended that geodatabases and equipment to track and assess all assets be made available to field staff and construction inspectors to ensure all staff are aware of the location and condition status of vegetation and roadside safety features. Access to asset information can enable state DOTs to reduce staff hours for mowing, herbicide application, and asset tracking, as the information could be automatically incorporated into the statewide tracking system.

These tools and technologies can also be used to keep records of all vegetation management (herbicide mowing, etc.). Records can be georeferenced and include any issues encountered during management, such as safety issues and invasive species locations. This would enable state DOT staff to locate areas where issues have occurred in the past and increase the amount of proactive work that can be done across the state, allowing state DOTs to properly plan, staff, and equip work activities. Targeting areas with past issues and working proactively can in turn reduce staff hours along the ROW, increasing the safety of both state DOT staff and the public.

It is recommended that a state DOT with a relatively small IT department purchase a system that allows for third-party IT support. This will be better for state DOTs with an IT department that may be unable to provide service for a proprietary software system, thus ensuring the tools and technology are updated when needed. It is recommended that the IT department reviews any system developed or purchased to ensure security permissions will be available, which may include ensuring third-party access when needed.

Terminology

It is recommended that state DOTs use structural asset terms as much as possible for RVAM activities to help facilitate RVAM advancement. In addition, it is recommended that terminology be similar across state lines. The Guidebook can be used as a starting point for incorporating terminology from across the US into a singular reference. It is recommended that state DOTs link RVAM assets to the state TAMP. This will help ensure funding for RVAM activities.

Condition Ratings

In addition to using common terminology, creating standardized asset condition ratings can enable local staff to better determine what work needs to be completed at any given time. This will help staff be aware of what is expected of vegetative assets and related safety assets. It can be helpful for state DOTs to follow a common rating system that includes assets such as culverts, guardrails, and others that are impacted by vegetation management. Some recommendations to ensure the condition ratings are helpful are:

• Define thresholds and goals for maintenance.
• Define “poor,” “fair,” and “good” conditions or similar rating condition system.
• Develop a condition rating system that follows the state DOT’s local goals.
• Use performance modeling or life cycle planning to determine maintenance cycles in advance rather than waiting for vegetation and vegetative safety feature failure.
• Conduct vegetative inventories to help central office and local staff be aware of the vegetative asset presence and management needs.

Defining maintenance thresholds and goals will help state DOTs to proactively plan RVAM activities. The thresholds and goals will directly tie into the condition ratings. Assessing condition ratings will allow state DOTs to complete performance modeling, and this modeling can be tied to the inventories state DOTs can complete. Performance modeling can enable state DOTs to operate proactively rather than reactively for maintenance, potentially reducing overall maintenance costs.

If state DOTs do not have dedicated DOT maintenance operations IT or GIS staff who can update software, a COTS system is recommended as this system will function without requiring DOT IT staff to implement the changes. A proprietary software system or a PCCA system will have higher IT maintenance needs, thus it is recommended for state DOTs with dedicated IT staff, as the department will be able to obtain updates to proprietary software systems or PCCA systems to maintain the systems’ relevance and security.

Staffing and Funding

Providing incentives for staff who take on additional responsibilities can encourage staff retention at the local level and can increase overall state DOT knowledge of available technology. These incentives can include a slight pay raise for staff who receive certain certifications beyond the state DOT’s requirements, such as herbicide applicators’ licenses. Some of the additional staffing recommendations are below:

• Assign GIS staff, local managers, upper management, and at least one central office staff member of the state DOT to engage in implementing the RVAM plan.
• Assign dedicated IT staff or IT staff who prioritize RVAM activities and needs for maintenance operations for increased success in developing and implementing RVAM systems.
• Assign dedicated GIS staff or GIS staff who prioritize RVAM activities and needs for maintenance/operations.
• Work with IT staff to identify the hardware and software requirements for IT support, data storage location, and manufacturing location of the new tools and technology.

• Communicate with IT staff to determine the capabilities of the IT department to assist with implementing new tools and technology. A system that allows for third-party IT support will better serve state DOTs with a small IT department that may be unable to provide service for a proprietary software system, thus ensuring tools and technology are updated when needed.
• Ensure field staff have access to up-to-date information, either through tablets, cellular devices, or other methods.
• Plan time for IT staff to train maintenance and office staff on proper technology use.
• Plan time for office staff to Quality Assurance and Quality Control (QA/QC).
• Dedicate a grant writer to help state DOTs locate and apply for federal funding.
• With the inclusion of the above recommended staff, state DOTs will have an easier time completing RVAM work and tracking associated costs across the DOT. This will, in turn, help the state DOT identify areas where additional funding would be helpful. This may also help provide justification to state legislatures for additional funds or to organizations granting funds to state DOTs. By including maintenance thresholds and condition rating systems, the state DOT will be able to demonstrate efficiencies gained with funding to these organizations or its legislature.

Federal and state funding may be available for the following activities:

• Flood mitigation
• Stormwater management
• Wildfire mitigation and prevention
• Tree inventories
• Threatened and endangered species (T&E species) protection
• Noxious/invasive plant and insect species eradication
• Wetland protection
• Wildlife crossings
• Pollinator/native habitat creation
• Social equity

It is recommended that a subcommittee and a pooled fund study be developed on a federal level. Both can assist with identifying funding sources and providing guidance on how best to receive the identified funding.

Subcommittee and RVAM Transportation Pooled Fund Research Study Formation

It is recommended that a subcommittee or multiple subcommittees (as needed) be developed within TRB. The subcommittee(s) can be sponsored by one or more of the following committees:

• AKR20 Standing Committee on Roadside Maintenance Operations
• AKD40 Standing Committee on Landscape and Environmental Design
• AEP70 Standing Committee on Environmental Analysis and Ecology
• AJE30 Standing Committee on Transportation Asset Management

If warranted, the following work could be completed by the AASHTO Subcommittee on Maintenance or AASHTO Innovation Initiative. The subcommittee(s) can assist with:

• Standardizing terminology and condition ratings
• Sharing information with state DOTs on new and upcoming technology
• Sharing open funding sources when they become available
• Assisting with developing state requirements

Including the committees above will ensure all information developed for RVAM is applicable to maintenance activities and that RVAM language is similar to the language used for structural assets.

It is recommended that the transportation pooled fund research study be open to researchers, state DOTs, and other transportation professionals and provide further guidance on the items listed below:

• Manage a pooled reserve to help fund RVAM research across the country.
• Facilitate demonstrations of tools and technology for RVAM.
• Help state DOTs with less advanced RVAM plans learn lessons from state DOTs with more advanced RVAM plans to improve success in RVAM plan implementation.
• Assist in developing marketing plans and communication materials for public outreach about industry standard RMPs.
• Assist with staff training through in-person and online training (videos, webinars, and courses) to reduce state DOT staff hours spent developing training materials.
• Develop an online database that includes, but is not limited to, a data dictionary focusing on RVAM assets and types of tools and technologies that can be utilized for RVAM.

Both the transportation pooled fund research study and the subcommittee can help develop tools for RVAM. It is recommended tools be created for the following:

• Measuring the safety risks of not removing or treating vegetation (sight distance, hazard threat, etc.).
• Measuring the safety, financial, and environmental benefits of having different types of vegetation in the ROW. This can include items such as:
  • – The extent to which native grasses, forbs, shrubs, and trees provide better soil stability and erosion control than turfgrasses.
  • – The extent to which native grasses and forbs provide better pollinator habitat than non-native vegetation species.
  • – The benefits of participation in the Monarch CCAA relative to costs for complying with the Endangered Species Act (ESA) during construction and maintenance projects and Monarch CCAA project fees.
  • – The impact of trees through tree canopy assessment tools, individual tree assessment tools, tools to assist with tree planting, measurements of carbon storage and sequestration, reduction in the heat island effect and air pollution, stormwater benefits, and influence on the health of the public (stress and reduced air pollution and regulated air temperatures, as available in software such as i-Tree).
  • – The potential for reducing the number of accidents due to both decreased equipment usage and decreased instances of implementing work zone speed reductions along the ROW.
  • – The acquisition/retention of scenic byway status, possibly increasing tourism.
• Using AI to interpret data; a human will need to perform quality control on the interpretation through ground-truthing or other methods.

These tools can be developed independently or through a project sponsored by the TRB subcommittee.

Outreach

There appears to be a lack of understanding among some state DOT staff and the public regarding the importance of, and need for, RMPs for RVAM. Increasing knowledge surrounding these assets, their benefits, and the understanding of each DOT’s individual goals can help improve the knowledge base of state DOT staff and private citizens. Potential benefits of these increased outreach efforts are:

• Reducing customer service tickets requests for mowing to make the ROW more similar to privately owned lawns.
• Improving local staff’s understanding of the reason for changes in certain maintenance activities, such as reduced mowing, or why certain plant species are not being targeted for removal.
• Increasing central office staff’s awareness of the vegetation maintenance work local staff complete.

• Developing the public’s understanding of how much work state DOT staff completes and the value of their efforts as public servants.
• Advancing state DOT staff’s and the public’s understanding of the importance of RVAM and vegetation in general regarding structural assets along the ROW and how ROW vegetation benefits surrounding properties and the state as a whole Advancing state DOT staff and the public’s understanding of DOT ROW’s impact on the spread of invasive vegetation and pest species.

Regional Requirements Versus Guidelines

It is recommended that state DOTs use requirements over guidelines, when allowed by state laws, to detail the type and amount of work DOT staff must complete. During the case studies and surveys, the research team found that state DOTs that use requirements instead of guidelines have more incidences of staff following state policy than state DOTs that set guidelines. The research team speculates that this might be because state DOTs with higher requirements for compliance may have greater staff accountability. This accountability is extremely helpful in ensuring staff complete the tasks assigned to them. An approach using minimum state DOT requirements is recommended, with counties having the freedom to determine operational details within the boundaries of those minimums. One example of this would be a state DOT requiring annual herbicide treatment for fifty acres of invasive vegetation within a management unit and local staff determining where the fifty acres of herbicide application will be completed and which species the applications will target.

To ensure the feasibility of these requirements, it is recommended that central office staff work with local staff to determine what goals can be met within the state DOT for that year based on past performance and equipment and staff availability. This can improve the performance of local staff, as they would have buy-in for the work plan and accountability for their actions throughout the year.

Possible Future Projects

Based on the research conducted during this study, the research team identified possible future projects. These projects are:

• Performance modeling wherein roadside asset performance ratings are tested to determine whether there are designs more aligned with state DOTs achieving RVAM goals. This project would review possible roadside asset materials for vegetation or safety features. An example could be testing the differences in the performance of living snow fences compared to metal, wood, and plastic snow fencing. This project would take into account the cost of the materials and installation, and the lifespan of the materials to determine which materials are best for use in the state DOT ROW.
• Create a Roadside Vegetation Condition Assessment Dashboard using insights from state DOTs that have already developed asset condition rating systems. This will enable additional state DOTs to establish their own vegetative asset condition rating systems and roadside safety feature asset rating systems more easily and will provide the ability for a national review of the status of the dashboards.
• Measuring the safety, financial, and environmental benefits of having different types of vegetation in the ROW. This project can develop a tool to measure the risks and benefits of RVAM through synthesis studies, or where applicable, explorative research. This project would go into further detail on the following research questions:
  • – Do native grasses, forbs, shrubs, and trees provide better soil stability and erosion control than turfgrasses?
  • – What are the benefits of native grasses and forbs for invasive plant species control?
  • – Does the installation of native habitat increase the population of small animals, such as pollinators or mammals in roadside corridors?

• • – What impact do trees have on carbon storage and sequestration, heat island effect, air pollution, managing stormwater to reduce flooding, and public health (such as reducing stress, reducing air pollution, and regulating air temperatures) for the state DOT?
  • – Does the reduced management that native species require (Davey Resource Group 2023) provide benefits through the reduction of the number of accidents due to decreased speed of equipment along the ROW?
  • – What are the benefits of acquiring/retaining scenic byway status? Do tourism dollars impact the state DOT and state in a positive way?
• The creation of a tool that uses AI to interpret data. The AI should be able to use data collected from across the state and use computer learning to be able to identify species—at least common invasive plant species—to enable state DOTs to automate the tracking of invasive species or other species that each state DOT wishes to track across time. AI could also be taught to complete surveys on sound walls, culverts, snow fences (both living and structural), guardrails, cable rails, and more. The software, over time, could be able to detect inconsistencies with asset conditions and inform state DOT staff where maintenance is required. During the project, it is recommended that humans perform quality control on the interpretation through ground-truthing or other methods to determine the cost-effectiveness of this technology for state DOTs.
• The development of a chapter in the AASHTO Guidelines for Vegetation Management on Mapping and Tracking Site Design Maintenance on RVAM. This chapter will have information included from this project, along with other vegetation-related projects, as applicable.