Managed Retreat Toolkit


Asset Relocation and Realignment

Introduction to Asset Relocation and Realignment

Beyond protecting or redesigning assets in-place, agencies can consider relocating (or “realigning”) as another alternative to formal disinvestment. Relocating or realigning roads, or high-risk segments of roads, to less vulnerable locations may offer a longer-term solution than design modifications or protective measures. This approach has been utilized in some coastal states to ensure longer-term safety of roads threatened by erosion, frequent inundation, or washout from storms and to reduce future maintenance needs of roads.

State DOTs in particular may be encouraged to consider options for realignment when dealing with coastal highways that are vulnerable to extreme events. Under Federal Highway Administration regulations, state DOTs are required to conduct periodic evaluations to determine if reasonable alternatives exist to roads, highways, or bridges that have repeatedly required repair and reconstruction activities due to emergency events such as natural disasters.See footnote 1

Erosion affecting State Route 1 in Sonoma County, CA, where Caltrans is pursuing a realignment project. Source: Caltrans. Erosion affecting SR 1 in Sonoma County, CA, where Caltrans is pursuing realignment. Source: Caltrans.

The intent is to encourage more cost-effective transportation planning and investment. The results of these evaluations are to be incorporated when state DOTs develop projects and are encouraged to be considered in long-range planning.See footnote 2 While these requirements do not apply at the municipal level, nor do they require analysis of repeated damage from non-emergency events such as high tide flooding, they may help encourage infrastructure agencies to plan proactively and build analyses and justifications for relocating infrastructure in high-risk coastal areas.See footnote 3



Asset Relocation and Realignment in a Managed Retreat Context

In the context of a coastal area considering the need for managed retreat in the future, a road relocation or realignment strategy is likely a temporary solution, albeit an often longer-term solution than design modifications or protective features. Where additional near-term managed retreat tools are being pursued, this strategy may not be necessary or appropriate as use of the road would be expected to dwindle as retreat tools are implemented, leading in the extreme to a scenario where a resilient road does not serve any community. Transportation agencies might consider developing a proactive phased approach to public infrastructure disinvestment as part of a managed retreat strategy, which may include road realignment as a strategy to bridge the gap (as with design modifications and protective features) to permanent disinvestment. However, this strategy comes with significant administrative and financial burdens, and accordingly agencies will likely reserve this option for the most critical or heavily used routes.

Policy Tradeoffs of Asset Relocation and Realignment


  • Road relocation and realignment is likely to require new right-of-way or other land acquisition, which can be administratively and financially challenging.
  • These projects therefore may have to undergo environmental review pursuant to the National Environmental Policy Act (NEPA)See footnote 4 and/or any state environmental review requirements (as applicable),See footnote 5 in addition to ensuring compliance with other environmental statutes. The level of administrative burden caused by environmental compliance will depend on the proposed location for the realigned road, including land ownership, land use(s), communities served or affected, and surroundings (e.g., environmentally sensitive land such as wetlands).


  • Relocating a road or section of road involves substantial costs, including to complete feasibility and other studies, secure permits, acquire needed land or right-of-way, and construct the new road. Accordingly, agencies may wish to reserve this option for corridors that are heavily used, are evacuation routes, or provide an important or sole means of access to communities, critical services, or other parts of the transportation network.
  • Environmental reviews and analyses and other permitting processes may require substantial upfront costs and time to complete.
  • However, the benefits of road realignment may outweigh the administrative and construction costs where the strategy is expected to significantly minimize or eliminate the need for any repairs beyond routine maintenance of pavement, for example, over the lifetime of the road.


  • Road relocation can provide environmental benefits by allowing the previous right-of-way to revert to natural conditions and provide a coastal buffer and opportunities for ecosystem migration.
  • However, this strategy involves building a road where one previously did not exist, and accordingly may also have negative environmental impacts, especially if sensitive ecosystems are disrupted. These impacts should be evaluated through environmental review and mitigated to the maximum extent possible.


  • Agencies considering road relocation and realignment should engage with communities that might be affected by the new siting and by any closures anticipated during construction, to gather public input and to provide information regarding any construction-related or permanent travel delays or other community impacts from detours or new route siting.
  • As roads typically provide the primary or only means of accessing the coast, decisionmakers may need to evaluate trade-offs of relocating roads inland and the effects on public access to the coast, and identify potential strategies to mitigate the effects on access. 


Practice Tips

When considering the need for relocating/realigning public infrastructure such as roads and bridges, as compared to alternative strategies (redesign in place, disinvestment), decisionmakers may wish to consider the following practice tips to balance policy tradeoffs:

  • Engage the public and communities likely to be affected by a road relocation or realignment strategy: This includes users who may be affected by any closures anticipated during construction or by the new siting of the route. Governments should solicit input through public meetings and active community outreach early in the planning process to identify community concerns and aim to address or mitigate them during siting, design, and construction.  For example, a realignment strategy may elicit concerns of loss of public access to the coast, travel delays, impacts to communities located near or around the original alignment and the proposed realignment, and more. In particular, residents and communities located in the areas proposed for a new road alignment should be engaged in the decisionmaking process at all stages in order to ensure that there will not be any adverse impacts to community cohesion or economies. Past practices relating to siting of the Interstate Highway System, for example, provide stark examples of how government decisions relating to infrastructure siting can destroy or isolate vibrant neighborhoods. Decisionmakers should learn from these mistakes of the past and view public and community engagement as a critical and ongoing component of the decisionmaking process in this context.
  • Develop robust analysis and projections of future conditions to inform a realignment strategy: Given the significant administrative and construction costs of this strategy, decisionmakers will want to ensure the relocated road will last under future conditions for the full desired lifetime of the asset. Therefore it is important to have robust science and data regarding coastal impacts that the existing road is experiencing, like tidal flooding and erosion, and to understand how those impacts may continue, change, or accelerate in the future to determine siting options that will ensure long-term safety of the road.
  • Integrate relocation and realignment strategies for high-risk coastal assets into transportation planning efforts and consider appropriate timing within asset management and investment cycles: As discussed above, state DOTs are required to develop risk-based asset management plans and to conduct periodic evaluations of alternatives to roads, highways, and bridges that have required repeated repairs due to emergency events. The information generated through periodic evaluations can inform both asset management and long-range planning and help transportation agencies evaluate timing of and potential funding to implement relocation and realignment strategies for repeatedly damaged roads.See footnote 6 For example, FHWA has clarified that both Federal-aid highway fundingSee footnote 7 and Emergency Relief (ER) fundingSee footnote 8 following disaster events can be used for resilience purposes, which may include design or protective measures and relocation strategies. In the case of ER funding, “betterments” that replace an asset with resilience improvements compared to the pre-disaster design or siting can be justified and federally reimbursed if the resilience improvement are required by newer standards in place at the time of disaster (e.g., state highway siting and design criteria) or if economically justified.See footnote 9  Agencies eligible to receive federal disaster recovery funding for transportation can therefore plan ahead by identifying opportunities to rebuild more resiliently in following the next storm event and by adjusting siting and design criteria, codes, and standards in advance of the next storm event.
  • Adopt an adaptive management approach: Policymakers can adopt approaches that “[track] hazards, impacts, costs, and effectiveness of adaptations and post-disaster response”See footnote 10 to inform future adaptation, realignment, or disinvestment policies and approaches. An adaptive management approach should consider the thresholds at which a protect-in-place strategy might give way to a realignment strategy, or at which a realignment strategy might give way to disinvestment as a more viable permanent solution. Thresholds might include environmental conditions such as the number of times inundated in a year, or policy triggers such as the implementation of other managed retreat tools that results in shifting public needs and priorities. Adaptive management should involve monitoring conditions proactively in order to leave time for planning and engagement around disinvestment strategies as threshold or “trigger” conditions are approaching.

Related Resources

Piedras Blancas Highway 1 Realignment - Caltrans/San Luis Obispo

The California Department of Transportation (Caltrans) realigned a 2.8 mile section of iconic Highway 1 to address current and anticipated impacts from coastal erosion and storm surge.  This section of Highway 1, which is north of the Piedras Blancas Lighthouse in San Luis Obispo County, was already experiencing increased storm damage from flooding and erosion, with these impacts projected to increase with rising sea levels and higher storm surge caused by climate change.  Realigning the highway away from the coast reduces its vulnerability to current damage as well as to future climate impacts and is anticipated to protect the highway from bluff retreat beyond the year 2100. The realigned section of the highway opened in 2017, allowing for the repurposing of the original alignment to add new sections of the California Coastal Trail, and for the restoration of land between the original and new alignments to provide coastal prairie and wetland habitats.

SPUR Ocean Beach Master Plan for San Francisco – Strategies for Great Highway

The Ocean Beach Master Plan (OBMP) provides a long-term strategy for responding to current and future sea-level rise impacts along the 3.5-mile stretch of San Francisco’s Ocean Beach, and provides recommendations for adapting the Great Highway, which runs adjacent to the beach. The strategy focuses on the protection and relocation of transportation infrastructure, including: (1) rerouting the southern portion of the Great Highway; (2) protecting and restoring the shoreline and beach; (3) reducing the width of the Great Highway; (4) repairing seaside dunes; (5) facilitating faster travel between Golden Gate Park and Ocean Beach; and (6) improving bicycle paths and sidewalks near Ocean Beach. The OBMP was developed by the San Francisco Planning and Urban Research Association (SPUR), a member-supported nonprofit organization that provides planning assistance to the San Francisco Bay Area, with financial support from the state coastal management program through the State Coastal Conservancy. In addition, some of the broad visions for addressing sea level rise and coastal erosion developed through the OBMP planning process were transformed into a set of land use policies that have been incorporated into the City and County of San Francisco’s Local Coastal Program, which was approved by the California Coastal Commission in 2018. SPUR continues to serve as coordinator and advocate for implementation of the OBMP, while city agencies are moving plan recommendations into implementation.

Surfer's Point Managed Shoreline Retreat Project

The City of Ventura, California, has had ongoing erosion at Surfer's Point, a popular surfing spot adjacent to the mouth of the Ventura River. A California State Park bike path along the shoreline and an adjacent County Fairground parking lot have also experienced frequent damage from erosion. State and local stakeholders collectively approved a plan to move the parking lot, pedestrian path, and bike path away from the tideline, instead of building a seawall or to adding other armoring, which was projected to permanently damage the beach and surf break. Phase I of construction was completed in 2011. Since then, Surfrider Foundation volunteers have been planting and maintaining sand dunes and bioswales with native vegetation, which protect the beach and water from stormwater runoff, and protect the bike path and parking lot from the waves.

Gleason Beach, California (Highway 1) Road Realignment Project

Transportation (Caltrans) is proposing to realign a section of Highway 1 near Gleason Beach in Sonoma County to provide long-term protection from coastal bluff erosion threatening the highway and surrounding area. The highway provides the only access between Bodega Bay and Jenner communities and is the sole vehicular route north to south for coastal Sonoma County. Multiple efforts since the late 1990s have sought to stabilize the roadway in place via various measures to shore up the bluff, but these protective measures cannot offer a reliable long-term solution. The proposed realignment is designed to provide a viable route beyond the year 2100 and includes provisions for restoring the lower beach from years of debris build up from failing structures. The project will also involve building a new bridge span in place of the current box culvert over a creek, wetlands, and archeological resources. Other project elements include significant public access benefits by securing public beach access and connecting segments of the California Coastal Trail. Additional benefits of the project are restoring aspects of the affected creek to promote salmonid use and allowing natural erosion processes to unfold over time.

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