Proceedings of a Workshop—in Brief

Convened April 7–9, 2025

Reinventing the Right of Way: Policy, Technical, and Economic Implications of Siting Transmission Lines Along Transportation Corridors
Proceedings of a Workshop—in Brief

Meeting the United States’ growing demand for reliable, resilient, and affordable energy will require expanded electric transmission capacity across the nation. As grid planners identify paths to accomplishing this expansion, the co-location of transmission lines along highway and rail rights of way (ROWs) may be one option for siting future transmission infrastructure. While this approach can potentially offer benefits for feasibility, cost-effectiveness, and public acceptance, there are few successful examples of this approach to date and many policy, logistical, design, and construction challenges to consider.

To provide a forum for discussing opportunities for the use of transportation ROWs for electrical transmission, the challenges involved, and potential solutions to overcome barriers, the National Academies of Sciences, Engineering, and Medicine (the National Academies) hosted the workshop on Reinventing the Right of Way: Policy, Technical, and Economic Implications of Siting Transmission Lines Along Transportation Corridors on April 7–9, 2025. The workshop convened stakeholders in the planning, operations, ownership, use, and regulation of transmission projects and transportation ROWs to establish a shared understanding of the issues and elicit constructive suggestions for action. The three-day event included more than 100 participants from state Departments of Transportation (DOTs), state and regional energy system offices and organizations, rail industry, federal entities, utilities and transmission developers, environmental and community groups, and research organizations. Attendees identified key barriers to locating transmission infrastructure within transportation ROWs; policies, supports, and business models that might advance such projects; and possible approaches or next steps for better coordination for co-location.

Workshop co-chairs Jacob Lucas (Eversource) and Roy Sturgill (Iowa State University) framed the current moment as a critical juncture for the nation. The demand for clean, reliable, and resilient energy is greater than ever before, and a robust electric grid is essential for daily life, the U.S. economy, and national security. Meeting these needs will require a significant buildout of electric grid infrastructure in many parts of the country. Sturgill drew a parallel between today’s challenges and the establishment of the interstate highway system in the mid-20th century, noting that, in addition to offering a conceptual example of the country’s capacity to successfully deploy large-scale infrastructure projects, the nation’s highways lay the groundwork for future grid expansion in a physical sense, as well. Exchanges amongst stakeholders in the workshop built connections

to better understand challenges across and amongst sectors and develop solutions to those challenges. This Proceedings of a Workshop—in Brief provides a high-level summary of the workshop discussions based on transcripts and recordings and does not necessarily represent the views of the National Academies.

CONTEXT AND LEARNING

The ability to efficiently move freight, people, and energy across the United States is vital to our national economy. Long, linear corridors needed for highway, rail, and electric transmission are often time-consuming and costly to secure, and in some cases, may not even be practically possible to develop, with the shared challenge of acquiring new land for utility and transportation projects. Co-locating transmission lines within existing transportation corridors could speed transmission project timelines, avoid opposition, and even enable otherwise impossible projects. Speakers provided an overview of the current status and future needs of the nation’s transportation and electric power systems along with the policy, regulatory, technical, and economic challenges associated with siting electric transmission facilities within transportation ROWs.

Co-Location Rationale and Challenges

Several speakers addressed the overarching rationale for co-location of transmission infrastructure in transportation ROWs along with some of the key challenges involved. Randy Satterfield (NextGen Highways) described how trends such as the electrification of transportation, the expansion of data centers, and continued buildout of renewable energy generation in rural areas mean that more transmission infrastructure will be required across the nation, especially in rural areas, which are increasingly burdened by grid infrastructure requests, and along highways, where electric vehicle charging capacity will become increasingly important. “Today, we’re in the process of making a generational investment in our infrastructure, and the success or failure of this investment will determine whether we can remain competitive in a global economy,” Satterfield noted. Against this backdrop, he said that co-locating transmission lines along transportation corridors can help to speed permitting and deployment, minimize impacts to agricultural lands and forests, and avoid public backlash by aligning with public preferences.

Despite the benefits of co-location, Satterfield, Rebecca O’Neil (Pacific Northwest National Laboratory [PNNL]), and other speakers pointed to legal, practical, and cultural barriers. A key issue is that most states have policy prohibitions or disincentives to co-locating transmission lines along interstates (or they leave it to the discretion of state DOTs’ Utility Accommodation Policies). However, a growing number of states are beginning to allow and promote the use of highway ROWs for transmission infrastructure.¹ Even when there is a will to co-locate transmission lines and the policy to allow it, there are numerous hurdles to enacting this vision. One issue, O’Neil said, is that the transportation and transmission sectors use fundamentally different planning paradigms. Plans are made and enacted by different authorities, with DOTs providing oversight throughout the process for highways and a constellation of different authorities playing a role in transmission planning. There are also key differences in financing; whereas highway transportation infrastructure is financed through public investment, transmission infrastructure is usually built using private capital or rate-based mechanisms. The time horizons are also quite different, making it challenging to align new transportation projects and new transmission projects. Geographic and jurisdictional boundaries also differ; jurisdictions are much more heterogeneous in the case of transmission infrastructure, and different states impose a wide range of authorities and requirements for transmission siting and permitting. Finally, O’Neil said that data gaps complicate planning and alignment; even determining where transportation ROWs exist is a challenging task for transmission planners, since this data is often unavailable or inconsistent across states. PNNL is working to collect data on all transmission projects involving transportation ROWs over the past 25 years, but it is unclear whether the information collected so far (reflecting 15 projects in total from 2000-2025) is comprehensive.

Satterfield noted that transmission developers and DOTs are highly siloed—and many have experienced friction when working together in other contexts, leading to fears that working together on co-located projects will only further complicate their processes. To illustrate that the barriers are real but not necessarily prohibitive, he

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described the successful deployment of the Badger-Coulee line, a transmission line built largely along an interstate highway after the state passed a law stating that highways and railways should be prioritized for siting new transmission lines. While the alternative off-highway route proposed for the line would have been shorter and slightly less expensive to build, regulators selected the co-located route because this option avoided impacts to an estimated 200-300 property owners. This example demonstrates that incentivizing co-location in policies and establishing memorandums of understanding (MOUs) between agencies can overcome barriers and foster fruitful collaboration. For this approach to be successful in other states and regions, Satterfield posited that stakeholders need to acknowledge the regulatory and other barriers that exist, while also recognizing that collaboration will pay off in the longer term. “Talking about building a collaborative planning process and doing it are two different things,” Satterfield noted. “What we’re proposing isn’t brain surgery, but it is hard work. But if we’re going to effectively build out transmission at the scale and speed required to meet the country’s future energy needs, we know we have to do things in a new way.”

In panel discussions, speakers delved deeper into the capabilities and constraints of the electric power system, highways, and rail to elucidate each sector’s perspectives, needs, and priorities relevant to co-location opportunities.

Electric Power System Perspectives

Speakers described key drivers and challenges the electric power industry faces in expanding transmission infrastructure. Rob Gramlich (Grid Strategies LLC), Granger Morgan (Carnegie Mellon University), and Jeff Dagle (PNNL) provided a national-level perspective, while Eric Johnson (ISO New England) and Greg Mathe (Dominion Energy) spoke to how these issues are playing out regionally in New England and Virginia, respectively.

Gramlich described the many drivers that have resulted in the need for increased transmission infrastructure—including growth in electricity demand from data centers, manufacturing, and vehicle and heating electrification—at a time when the buildout of new transmission lines has actually slowed. Given the economies of scale in terms of both cost per mile and the amount of land used, Gramlich underscored the need for a coordinated, large-scale approach to this transmission infrastructure buildout, rather than incremental additions. Morgan noted that two recent U.S. Department of Energy (DOE) studies outline a need to more than double the capacity of the nation’s high-voltage transmission system by 2050,^2,3 but neither study addresses the issue of how to get the new transmission built. A slowdown of new transmission deployment, combined with soaring energy demands and new generation interconnection backlogs, presages a significant bottleneck in the nation’s ability to move power from where it is generated to where it is needed and assure system reliability, affordability, and resilience. The two main strategies for addressing this are to expand the amount of power that can be moved through existing transmission corridors or to deploy more transmission lines in traditional or non-traditional rights of way. To determine the optimal strategies, Morgan emphasized the need to consider trade-offs in terms of engineering, costs, and public acceptance.

Despite the clear need for and benefits of new transmission infrastructure, significant barriers impede buildout. Gramlich pointed to a lack of proactive, long-term, multipurpose planning in the electric power industry as a key barrier. A second barrier relates to the complex local, state, and federal approvals necessary to obtain permits to build transmission infrastructure. Finally, there are gaps in the policy and regulatory structures regarding who pays for transmission lines across states. These barriers—collectively referred to as the “3 Ps” of planning, permitting, and paying—are substantial, but Gramlich said that experience has demonstrated it is possible to overcome them.

It is useful to understand the key stakeholders involved in grid planning. Economic regulators, including the Federal Energy Regulatory Commission (FERC) and state public utility commissions, play a key role, and Gramlich pointed to FERC Order Number 1920⁴ as an important factor influencing regional transmission planning. Other

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stakeholders include electric utilities, market operators (independent system operators and regional transmission organizations [RTOs]) and the North American Electric Reliability Corporation, which regulates electric utilities from a reliability perspective. Others with an interest in grid infrastructure include consumers, non-governmental organizations, independent power producers, the clean energy industry, and those who develop and build transmission infrastructure.

The U.S. electric power grid is operated by approximately 3,000 entities of many types. Dagle described how these entities have connected together to form three large transmission systems, allowing them to benefit from economies of scale, shared reserves, load diversity, and supply diversity. However, they remain 3,000 separate entities and operate across numerous state and other jurisdictional boundaries, creating a complex landscape of policies, capabilities, and incentives. The fragmented engineering, business, and regulatory structure of the electric grid makes it difficult to build long-distance electric transmission that involves many different entities which may have different objectives, with some existing and new system participants benefiting and others facing costs. Dagle also underscored the impact of contingency planning on transmission requirements. Since electricity moves far faster than it can be controlled in a given instant, contingency planning and proactive corrective actions are essential to maintaining grid stability, and availability of transmission resources is part of addressing those contingencies.

Johnson and Mathe described how shifting load forecasts, seasonal peaks, and new power generation sources have increased the need for, and complexity of, transmission planning in their regions and from the perspective of a regional systems operator and a private electric utility, respectively. Pointing to examples in Virginia’s “data center alley,” Mathe highlighted the challenges Dominion Power encountered in siting transmission lines along highway corridors, including misaligned planning timelines, complex design requirements, and public resistance. While it may seem like there would be advantages to co-planning a transmission expansion along with a highway expansion (as happened with a project along I-66), Mathe noted that such an approach can also make for a moving target and add further complexity.

Highway System Perspectives

State DOTs are charged with maintaining their ROWs for public transportation needs, but they also have the authority to accommodate utilities within their ROWs according to Federal and state policies. Speakers described engineering, logistics, policy, and other issues when considering utility accommodations within highway ROWs. Julie Johnston (Federal Highway Administration [FHWA]) noted that, while the accommodation of utilities along highways is considered to be in the public interest, a variety of rules and regulations influence which utility accommodations are allowed and approved. To be eligible for accommodation in the ROW, a utility line must ultimately serve the public; private lines that serve a limited number of people or connect privately owned assets with each other are not considered public serving. Other rules may also restrict the locations where eligible utility lines are accommodated; for example, new installations may be prohibited in portions of ROWs that are designated as scenic, historic, or as a wildlife refuge. States also have jurisdiction to determine whether utility lines can be located along highways and under what circumstances these accommodations may occur, including the ability to prohibit utility co-location, permit it in some cases and prohibit it in others, and to set fees for these accommodations at the state’s discretion.

As co-location proposals move forward, there are many requirements and considerations that influence where and how utility lines are installed. These generally relate to safety, operations, and/or aesthetics, and include rules related to the location of utility poles and lines relative to the roadway “clear zone,” distances from bridges, design guidelines for reducing safety hazards, especially for poles and posts, and specifications around the mapping and marking of lines installed underground, among other rules. In addition, there are considerations around the construction process of the utilities pertinent to access, oversight, and worker safety. It is also critical to plan for ongoing maintenance and inspection processes and determine who pays for relocation if it becomes necessary in the future. The FHWA offers resources to navigate these rules and considerations.⁵

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Drew Gilmore (Ohio DOT) highlighted the underlying principle of using public land for public good as a central consideration for DOTs, and one that also can harmonize with the fundamental goals of the electric power grid. Speakers with experience in managing DOT ROWs and utility accommodation policies in Texas, Utah, Wisconsin, and Minnesota offered perspectives on the goals, needs, and constraints of state DOTs in this space. Many of the constraints are well established and codified in law; for example, Leonel Tovar (Texas DOT) outlined Texas’ rules around vertical and horizontal clearances, pole sizes, underground line depth and encasement, and the need to prioritize public safety when considering exceptions for utility accommodations. Brian Christensen (Horrocks) described an example of how voluntary guidance can help to harmonize ROW utilization, noting that Utah’s “dig once” preference helps to increase efficiency and reduce transportation disruptions by encouraging multiple utilities to perform work in tandem utilizing the same trench and space.

Wisconsin’s DOT was one of the first to place a value on its ROW and allow accommodation of transmission facilities. Bob Fasick (Wisconsin DOT) offered a brief history of the decision making that led to this approach and how it has played out over time. For decades after the national interstate highway system was established, Wisconsin, like most states, allowed utility crossings but prohibited longitudinal accommodations along its highways. In the 1990s, these rules were loosened, and utility companies began requesting the use of highway ROWs for telecommunications and other infrastructure. This eventually expanded into a push to allow longitudinal accommodation of electric transmission lines, and new rules were put in place in the early 2000s. Today, both crossings and longitudinal accommodations are allowed for electric transmission lines and there have been 27 projects to make use of longitudinal accommodations, with seven using interstate ROW. Given the many issues that utility accommodations can pose for highways and the value ROWs hold for DOTs, Fasick said Wisconsin determined that ROW access should not be given away for free and established two main fees: one for the occupation and accommodation, and one to provide compensation for trees removed for the installation of the utility infrastructure. The fees amounted to $10,000 per mile for occupation and $200 per tree removed; in the case of the Badger-Coulee electric transmission line, fees totaled just over $600,000 for occupation and about $9 million for the removal of 45,000 trees.

Although the co-location of utilities in roadway ROW might seem logical from the perspective of the public interest, Jessica Oh (Minnesota DOT) said it is critical to recognize that DOTs purchase their ROWs to support their mission to provide safe transportation to the public, and a request to use the ROW in ways that potentially could interfere with DOT goals requires careful consideration and justification. Even seemingly empty roadsides can serve a variety of valuable purposes, including providing areas for vehicle recovery and snow storage; accommodating other utilities such as fiber optic lines, gas lines, and water pipes; and environmental purposes such as supporting protected species, carbon capture, water infiltration, and erosion control. ROWs also provides DOTs the flexibility to make changes to the roadway, such as space for adding lanes or interchanges in the future. In considering utility accommodation requests, Oh said that DOTs weigh many trade-offs involved, but safety is typically the top concern. She noted that budgetary and staffing constraints limit the capacity of staff to process requests, and coordinating with utilities and dealing with downstream utility impacts can add costs for DOTs, which they may not have the option to recover. Oh highlighted considerations around the impacts of construction and maintenance of the electric infrastructure on the operations and maintenance of the roadway, and Fasick added that co-location can create many issues around access and safety, driver distractions, induced voltage, and grounding issues. In addition, Oh noted that there can be impacts on scenic viewsheds, sensitive species and environments, and culturally significant areas, which tie into public perceptions and societal values.

Despite the challenges, Oh, Fasick, Gilmore, and other speakers noted that there are increasing motivators to facilitate coordination among DOTs and electric system planners for the public good, emphasizing the importance of relationship building in this process. While clear rules and guidelines are critical, Gilmore noted that to get to a place where co-location is more practical requires getting to a place where more collaboration is possible, both in terms of logistics and culture. “As much as we like to

think […] it’s just about concrete and asphalt and steel and wires, I think it’s really about people—it’s really about talking and communicating,” said Gilmore.

Rail System Perspectives

Railways represent another extensive network of transportation corridors across the United States that provide opportunities for co-locating transmission lines within existing ROWs. Speaking to considerations around utility accommodations in railroad ROWs, Karin Stamy (North Carolina Railroad Company) and Theresa Romanosky (Association of American Railroads) emphasized that one key difference between railroads and highways is that railroads are privately held or publicly traded companies, not utilities or government-run assets. Accordingly, there can be fewer constraints and faster timelines associated with co-location in railroad rights of way, provided that the parties reach acceptable arrangements with each other.

Collectively, railroads are among the largest private landowners in the United States, with a network spanning nearly 140,000 miles across North America. Despite their different ownership structures, Alex Saar (CSX) noted that operators of the nation’s railroads share a fundamental similarity with those who operate highways in their overarching mission to safely move goods and people from place to place. Similarly, any accommodation of utilities in their ROW must not come at the cost of those overarching priorities, necessitating careful consideration around design and engineering, construction and access, and ongoing maintenance.

There is a long history of co-location of utilities along rail lines, and railroads have well-established processes for contracts and fees associated with the use of their ROWs. Although the process varies from operator to operator, speakers said that the journey from the submission of an application through approvals and construction can be long, requiring robust planning and communication. Romanosky explained that this is because of the complexity inherent to ensuring permitted installations will be safe and workable for many decades. While a railroad track may seem simple, it is in fact a highly engineered space. To support safe and reliable operations of the railway, anything installed across or along tracks must be properly engineered so as to not interfere with the track structure, communications infrastructure, anti-collision technology, or railroad crossing warning devices. Designs for utility installations therefore need to be sufficiently complete and feasible to provide these assurances.

Romanosky noted that railway ROWs exist in a wide variety of ownership structures, which affects the types of contracts railways can make for utility accommodations in their ROWs. In negotiating contracts, Moises Young (Amtrak) noted that railroads specify a variety of details, including who bears the cost if relocation of utility infrastructure becomes necessary in the future. He emphasized the importance of close collaboration to ensure plans are feasible and construction runs smoothly. Saar added that railroads might have ROWs where tracks have not been installed and which may not be as obviously available for consideration. He recommended that utilities reach out to railroads to ask about ROW options early in their planning processes.

Romanosky highlighted several considerations railroads focus on when evaluating applications. For proposed aerial installations, it is critical to avoid situations where a train could snag on an overhead line and pull it down, creating a safety hazard. For underground installations, it is important to avoid subsidence, which can undermine the integrity of the rail bed, and to avoid interfering with railroad signaling equipment or equipment that may already be installed in the space such as gas and water pipelines. Saar added that in general, railroad operators prefer designs in which the utility installations are as far to the edge of the railway ROW as possible so as to avoid electric interference with railway systems and also to allow for greater flexibility for any future changes.

Speakers also underscored the importance of collaboration around maintenance and emergency response. Maintenance for utilities is often planned years in advance, and Young said it is important to inform railroads of maintenance activities so that they can have personnel onsite when needed; he also noted that utilities and railroads can help each other by communicating about any issues with the other party’s infrastructure that may be noticed during routine inspections. He also added that railroads and utilities need to collaborate to respond quickly when infrastructure fails or becomes damaged, whether the problem is on the utility side (such

as a downed pole) or on the railroad side, to ensure both parties are able to protect public safety and resume operations quickly.

Although railroads have a long history of utility co-location in general, examples of transmission lines installed longitudinally along railways are currently limited. James Hoecker (Rail-Grid Collaborative) pointed to the Champlain Hudson Power Express, currently under construction, as one example demonstrating the feasibility of longitudinal co-location of transmission infrastructure. That project is installing about 100 miles of transmission line along a CSX rail line in New York State as part of an approximately 300-mile, 1250 MW high-voltage direct current line running from the Canadian border to New York City. The SOO Green project will also take advantage of railroad ROWs in three areas as part of a project that will convey wind and solar energy from the Midwest to the eastern electric power market.

POLICY STATUS AND OPPORTUNITIES

Policies at various levels influence whether and under what circumstances the co-location of transmission facilities within transportation ROWs is allowable, feasible, and cost-effective. Speakers explored the role of state and federal government and policy leaders and discussed possible actions that could be taken to advance the consideration of transmission co-location.

To understand what policy levers are likely to be most impactful for facilitating co-location, Ted Thomas (Energize Strategies) emphasized the need to recognize the economics by which the electric grid operates and the context in which transmission planning occurs. A network whose operation must be planned and managed, the electric power grid includes both capacity (the capability to produce electricity) and energy (the electricity that is actually transmitted). Substations are the nodes in the network where high-voltage electricity carried by transmission lines from energy generation sources is stepped down to a lower voltage for distribution. Substations are where electricity prices can be set in some market-based systems, and these nodes drive the fundamental economics of transmission planning. A robust transmission system enables grid operators to ensure system reliability, access lower-cost generation sources, and increase resiliency. While some utilities can earn a favorable rate of return on transmission infrastructure they build, the benefits of transmission investments to many utilities and other stakeholders are reaped in the form of future cost savings, primarily stemming from the ability to access lower-cost generation sources. There are significant economies of scale in building out a bigger grid to head off potential reliability problems that can result from underdeveloped transmission, but this is a complex challenge to achieve. Leveraging transportation ROWs for the grid requires transparency on the rules and requirements involved, collaboration among governmental entities, and an alignment between existing ROWs and grid needs in a way that reduces costs for transmission planners and developers, Thomas said.

John Kaliski (Cambridge Systematics) discussed how the use and management of transportation ROWs fits into broader efforts to improve the nation’s transportation infrastructure as outlined in a project of the National Academies and the American Association of State Highway and Transportation Officials (AASHTO).⁶ Mapping ROWs for conduit suitability and developing DOT ROW asset management plans is one of 12 levers of change the project identified for facilitating further progress, alongside other levers such as leadership and culture, partnerships, policies and regulations, alignment of processes, human resources capacity, and organization and governance.

Speakers discussed models that offer lessons in navigating the policy landscape around transmission infrastructure in transportation ROWs. Maury Galbraith (Colorado Electric Transmission Authority [CETA]) described how CETA, an independent public body, has been instrumental in supporting transmission capacity expansion in and around Colorado. Created in 2001, CETA has authority to partner with public or private entities to establish transmission corridors, to issue revenue bonds to finance transmission projects, and to use eminent domain to acquire transmission ROWs. CETA also partnered with NextGen Highways to create a Colorado framework requiring transmission developers to prioritize utilizing existing utility corridors where possible, then consider

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co-location in state highway ROWs, and only pursue greenfield development in new areas as a last resort.

Speakers throughout the workshop noted that state-level prohibitions on the co-location of transmission lines in interstate highway ROWs are a key barrier. Galbraith said that removing such prohibitions would allow planners to consider co-location as an option (though not a mandate, he emphasized), providing a basis to start a conversation on whether and where it makes sense to pursue co-location. To avoid prolonged planning processes that ultimately go nowhere, Thomas, Kaliski, and Galbraith said that planners need tools to quickly screen for places where it might be beneficial to co-locate transmission lines along transportation ROWs. Such tools require basic information about where ROWs are located and where they might be suitable for accommodating transmission infrastructure. Collaborating early in the process can help both sides identify use cases where co-location could be feasible and mutually beneficial.

Economic considerations are important to all stakeholders. Kaliski said that it is key to articulate the business case for co-location from a grid perspective and also for economic development. Galbraith emphasized the importance of timing; since the economic benefits of transmission infrastructure come from generation of cost savings, delaying transmission development is inefficient and ultimately costly for the utility. However, Thomas posited that the lack of a strong business case for DOTs to accommodate utilities creates a challenge for aligning incentives without an expanded mission and mandate on the part of DOTs.

Chris Fletcher (National Governor’s Association) highlighted the role of state governors in garnering public support and cross-sector collaboration to facilitate transmission development. Although governors have no formal role in transmission development, infrastructure is vital for advancing the priorities of many governors, and expanding transmission capacity can be seen as a means to attract businesses and support economic development, protect energy affordability, and support disaster resilience. As highly visible public figures and the executives of their state government, governors have a unique ability to bring people and organizations together and advocate for grid infrastructure improvements. In addition, they can facilitate regional coordination; for example, a Governors Working Group on Permitting Energy Infrastructure is being formed to advance best practices on permitting, such as creating centralized authority. Fletcher said that considering the use of transportation ROWs for electric transmission infrastructure can create greater flexibility and speed implementation.

Given that state DOT workforces are already constrained in terms of personnel, time, and resources, several speakers underscored the importance of ensuring agencies have the resources they need to collaborate with utilities around co-location opportunities. They also emphasized the critical importance of finding common ground, communicating effectively, and forging relationships across silos. “Key to all of this is collaboration, […] relationships, and building trust,” Galbraith said. “In addition to removing the barrier, which sort of resets everything, you need positive direction to make this happen, and the way you will make it happen is through partnerships.” He added that in addition to working effectively across sectors and agencies, this collaborative approach should include open, ethical, and equitable engagement with affected communities.

IMPLEMENTATION ISSUES AND OPPORTUNITIES

To identify opportunities to facilitate transmission infrastructure co-location along transportation ROWs, workshop participants joined breakout discussions examining key issues from highway, railway, and electric transmission perspectives. Speakers also discussed geospatial and siting considerations and shared tools that can aid with co-location efforts.

Highway Issues

Kenny Franklin (Parsons Corporation) summarized the discussion of issues highway agencies face in considering transmission co-location within the highway ROW. He stressed that even before tackling the engineering, policy, and logistical issues, it is important to recognize the deeply-rooted experiences DOTs have in collaborating with utilities for ROW use. For DOTs, a lack of coordination from utilities is seen as a major contributor to delays in roadway construction, which is a pain point for DOTs that goes beyond increased project cost. Delays can cause frustration among DOT stakeholders like landowners and business owners affected when construction drags on too long. To recognize and begin to address the reluctance

engendered by the prospect of even more collaboration and accommodation of utilities, he said it will be vital to focus on understanding of different perspectives and priorities on both sides, developing relationships to work across silos, and perseverance to work through tough issues. Another barrier relates to resources: many state DOTs are already struggling to manage permitting and often have only enough capacity to do the bare minimum in supervising implementation. Against these headwinds, he said that the burden is on the utilities to convince DOTs that it is worth collaborating on co-location projects. “There’s a massive mindset difference between a multibillion dollar revenue-generating world and the public service that the DOTs provide—those worlds drive your thinking,” Franklin said. To justify pursuing co-location projects in light of the potential risks involved, he said that DOTs will be looking to utilities to “help us solve the existing problems as we help solve your newer concerns.” Even so, he noted that DOTs understand the value of collaboration as a potential solution to growing needs and are willing to seek greater understanding and identify the terms and conditions that can make co-location a viable option.

Participants also discussed the importance of attending to access, safety, ROW acquisition, and the potential for multi-use conduits for underground infrastructure, along with opportunities to enhance collaboration by linking transmission corridors with major new highway projects to allow for co-planning. From a policy perspective, they identified a need for advance planning regarding how the ROW asset will be managed and dovetailing that with utility accommodation policies. They also raised the option of separating high-voltage transmission from distribution infrastructure in these policies.

Rail Issues

Stamy summarized the discussions of key issues from the perspective of the rail sector. To overcome internal and external barriers, participants highlighted the importance of communication and focusing on finding common ground. Stamy noted that the rail and electric power industries share a focus on safety, reliability, and efficiency, as well as a cultural proclivity to focus on their own sector. Each has different planning processes, which have historically not heavily emphasized the consideration of rail ROWs for transmission infrastructure, and participants suggested that it might help to expand planning guidelines to embed this option more explicitly into the process for both sides.

In addition, participants recognized that a lack of information on rail ROW locations and how much it might cost to install transmission infrastructure along them has been a hindrance. However, Stamy said that the discussions at the workshop have made it clear that these are questions worth asking and it is possible to get answers by knowing who to call. She noted that organizations such as AASHTO and the American Short Line and Railroad Association can act as conveners to facilitate collaboration—and added that a Rail-Grid Collaborative is being launched, which could play a role in coordinating around transmission infrastructure in rail ROWs. “From a railroad standpoint, there is revenue to be gained by leveraging your assets where you can, and for transmission providers it is probably cheaper and faster to locate in an existing right of way,” she noted. “I see lots of win-wins here, but we have to get everyone talking to each other.”

Transmission Issues

Donna Brutkoski (NextGen Highways) said the transmission-focused discussion examined regulatory and policy barriers, safety issues, maintenance and relocation, cost allocation and financial risk, legal ambiguities and institutional resistance, and public and stakeholder engagement considerations. Participants noted the misalignment in timelines for planning transportation versus transmission infrastructure. Early visioning and pre-planning engagement can help stakeholders establish trust and learn to communicate across sectors and silos; however, it is important to recognize that in the context of transmission, the earlier you start the less you know about what infrastructure is needed. Collaboration can be improved by understanding the pressure points for both the transmission developer and DOTs to guide go/no-go decisions. Participants also identified important data gaps and potential areas of misalignment in goals and processes when looking at the big picture versus a more granular level, and when examining the local scale versus regional or interregional spatial scales. There can also be variation in culture and business models among different RTOs, further complicating collaboration. Overall, participants said that transmission planners would

like to see clearer criteria from regulators regarding what determines whether a project gets approved.

Geospatial and Siting Considerations and Tools

Throughout the workshop, participants noted the critical role of data in determining which ROWs may be suitable for collocating transmission infrastructure. Joe Simon and Stan Young (NREL) joined Allie Kelly (The Ray) for a discussion of what types of data are most useful, barriers to obtaining needed data, and opportunities to overcome those barriers. In the discussion, Young and Kelly, along with members of the audience, identified regulatory considerations as a key driver of suitability and a barrier to implementation in some cases. Young suggested that having direct access to utility accommodations policies across all 50 states would be a useful resource for screening freeways and state highways for colocation suitability. Other key factors in determining suitability include costs, environmental and safety considerations, and technical and design considerations. Geospatial characteristics underlie all of these factors, including subsurface characteristics, soil conditions, existing underground structures, and environmental constraints.

Kelly explained how The Ray has sought to address this data gap and facilitate projects through a partnership with ESRI to develop ROW suitability mapping tools for both overhead and underground transmission lines. These tools incorporate available data on topography, vegetation, existing infrastructure, future transportation project development plans, and many other factors to generate optimal paths which planners can then refine and use to generate a rough estimate of build cost. By providing a basis for virtually planning real colocation projects, she emphasized that the tool can help stakeholders build trust and work together more effectively than they may have done in the past. “This is the table that gathers the stakeholders around what people can believe in, which is the data,” Kelly said.

SUGGESTED ACTIONS

A second breakout session identified suggested actions for highway and electric transmission leaders to resolve challenges and facilitate co-location. Edgar Kraus (Texas A&M Transportation Institute) summarized the suggestions focused on the highway perspective, Jennifer Yoshimura (PNNL) summarized the suggestions focused on the transmission perspective, and workshop co-chairs Sturgill and Lucas facilitated an interactive activity to solicit feedback from attendees on the feasibility and impact of the suggestions that were identified. Participants in both the highway and transmission groups emphasized communication and trust, which Yoshimura noted could be aided by pre-planning engagements, regular check-ins, and ultimately MOUs. Yoshimura added that quasi-government entities and state consortiums could be helpful for supporting knowledge sharing, bringing all relevant stakeholders to the table, and creating incentive mechanisms for effective collaboration. Both groups also emphasized the value of standardization of policies and procedures, including within states, where commissioners are often left to use their own discretion in determining which projects move forward, and across states, to enable regional projects. Kraus added that DOTs would benefit from establishing a point person, perhaps someone with dual functions across agencies, for coordinating utility accommodation partnerships; however, given the constraints DOTs already face, an appropriate allocation of resources would be needed to support this type of work.

The actions suggested by individual participants in the breakout session were grouped into 10 main ideas, which attendees ranked in descending order of priority as follows:

1. Collaborative planning and data exchange for siting and design; consider corridors and standard ROW valuation
2. Standardization of process, requirements, and procedures for accommodations, with MOUs
3. Joint task force/consortium at state levels for regular meetings and exchanges
4. Educational resources/guide to understand each others’ procedures and requirements
5. Liaison/coordinator across groups, perhaps dual funded
6. Alignment and process timelines and deliverables
7. Develop non-discretionary criteria for siting and transmission alternative selections

8. Transmission provided resource/fees to facilitate DOT accommodations
9. Consider transmission as a transportation system
10. Establish a state level agency with the authority for DOT and transmission siting priorities

Approximately 50 in-person attendees used an interactive voting system to rate each priority in terms of effort and impact; the results are presented in Figure 1.

REFLECTIONS

In closing reflections, members of the workshop organizing committee underscored the value of focusing on shared goals and identifying avenues for collaboration. The workshop discussions demonstrated that people from many stakeholder groups are willing to engage with each other and explore where and when co-location might be a viable option that will ultimately benefit the public, who are both the taxpayers who support the nation’s highways and the ratepayers who purchase electricity. There was a great deal of overlap in the ideas presented by those from the transportation and transmission sectors, with a shared emphasis on building trust, sharing information, having personnel in a position to facilitate collaboration, and establishing productive processes. “I think that this conference equipped us with the resources to ask the right people targeted questions to move the needle forward,” said Aisha Moultrie (Georgia DOT).

Catherine Reed (National Association of State Energy Officials) added that the workshop also demonstrated that planners are not starting from scratch, but have tools, models, and case studies to build from, such as the experiences in Wisconsin, Minnesota, and Colorado and insights from The Ray and PNNL. Although there will inevitably be trade-offs stemming from the different roles and goals of the nation’s electric grid and transportation systems, both ultimately share the goal of supporting a thriving economy for states and the nation. To bring the ideas generated at the workshop to fruition, Sturgill noted that grand, holistic plans may be the ideal but there are things every stakeholder can do now to move the ball forward within their own organization, stating: “It can be a very small task that could have a very big impact.”

DISCLAIMER This Proceedings of a Workshop—in Brief was prepared by Anne Frances Johnson, Alex Temple, and Elizabeth Zeitler as a factual summary of what occurred at the workshop. The statements made are those of the rapporteurs or individual workshop participants and do not necessarily represent the views of all workshop participants; the planning committee; or the National Academies of Sciences, Engineering, and Medicine.

PLANNING COMMITTEE Jacob E. Lucas (Co-Chair), Eversource; Roy E. Sturgill (Co-Chair), Iowa State University; James W. Kirk, II, Texas Department of Transportation; M. Granger Morgan, Carnegie Mellon University; Aisha Moultrie, Georgia Department of Transportation; Catherine Reed, National Association of State Energy Officials; Karin Stamy, North Carolina Railroad. The National Academies’ planning committees are solely responsible for organizing the workshop, identifying topics, and choosing speakers. Responsibility for the final content rests entirely with the rapporteurs and the National Academies.

REVIEWERS To ensure that it meets institutional standards for quality and objectivity, this Proceedings of a Workshop—in Brief was reviewed by Jeffery Dagle, Pacific Northwest National Laboratory; Jessica Oh, Minnesota Department of Transportation; and Matthew Prorok, Great Plains Institute. Marilyn Baker, National Academies of Sciences, Engineering, and Medicine, served as the review coordinator.

SPONSORS This activity was supported by contracts between the National Academy of Sciences and the Arthur M. Blank Family Foundation, the U.S. Department of Energy Joint Office of Energy, and Transportation and Grid Deployment Office. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

STAFF Alex Temple, Program Officer, PGA; Chris McKenney, Senior Program Officer, TRB; Elizabeth Zeitler, Board Director (acting), DEPS; and Marshall Bradshaw, Senior Program Officer, PGA.

SUGGESTED CITATION National Academies of Sciences, Engineering, and Medicine. 2025. Reinventing the Right of Way: Policy, Technical, and Economic Implications of Siting Transmission Lines Along Transportation Corridors: Proceedings of a Workshop—in Brief. Washington, DC: National Academies Press. https://doi.org/10.17226/29178.

For additional information regarding the workshop, visit https://www.nationalacademies.org/our-work/reinventing-the-right-of-way-policy-technical-and-economic-implications-of-siting-transmission-lines-along-federal-aid-highways-a-workshop.

Division on Engineering and Physical Sciences Policy and Global Affairs Transportation Research Board Copyright 2025 by the National Academy of Sciences. All rights reserved.