Why is this project being recommended in Stella?  

After consideration of engineering, economic, environmental, and social factors, the recommended plan for the Rincón Planning Reach is acquisition of approximately 70 parcels along the Rincón shoreline from R11 to R19, or just south of Quebrada Los Ramos to just north of the Condominio Costa Corcega. These properties are the most vulnerable, and modeling predicted that 75% of these structures would be severely impacted by hurricanes and storms and would be condemned for safety reasons within the next 25 years, given the high levels of predicted damage. Additionally, these structures were shown to have an adverse effect on the coastal system from associated erosion damages and are recommended to be acquired. The acquired properties would be reestablished as natural coastline (beach) that would support environmental enhancement, public recreation, and future economic growth and stability. Once acquired, these properties would become part of the maritime terrestrial zone and future development would be prohibited, ensuring the beach area remains natural, open to the public, and undeveloped.  

How was the acquisition footprint developed?  

The proposed alternative and structure acquisition footprint were selected based on numerous factors, the most significant of which are described below. First, the study team considered predicted structure damages from planning models and their physical location in relation to the existing water line. Additionally, the team considered potential impacts to natural coastal processes (at present and into the future) due to coastal armoring or structures that exacerbate erosion. The study team also aimed to avoid adverse impacts to environmental resources (such as nearshore vegetation beds and hardbottom corals and sponges), and to restore sandy beach areas for sea turtle nesting and shoreline bird habitat.  

What is the process for homeowners in the acquisition footprint if this plan is implemented?  

If this plan is implemented, homeowners would negotiate selling prices for their home, based on fair market value and if they qualify, they would be provided relocation assistance to move to new homes. An essential part of this plan is that homeowners are given compensation for their homes at fair market value while homes are in peak condition, prior to catastrophic damages occurring to homes from hurricanes and storms.  Information about the acquisition process can be found in the real estate acquisition brochure located on the study website. 

How do we know what environmental resources are in the area? 

A team of marine scientists conducted in situ identifications of submerged resources and delineated and mapped submerged aquatic vegetation (SAV) and hardbottom habitat, endangered species act (ESA) listed corals, and other important marine resources occurring within the Rincón study area. The benthic resource surveys were conducted during three separate field efforts occurring from 17 July to 9 October 2022. Inventories identified extensive coral reef and SAV resources in Rincón. Mantee and sea turtles were both observed feeding in the area. The benthic assessment and shoreline structure survey also identified and delineated resources as essential fish habitat (EFH) within the project area. The Final Environmental Survey Report was received on 31 January 2023.  The survey report was valuable to refining assumptions for the study analysis and is posted on the study webpage. Based upon the results of benthic habitat and species mapping and characterization surveys, the Rincón area provides diverse aquatic habitats.  This survey report is available to the public for use and is posted on the study website. 

What are the environmental resources in the area?  

The existing nearshore supports an ever shifting, diverse physical and biological nearshore aquatic grassland and coral reef system; however, the shoreline has been modified in the past. ESA-listed coral species were located and identified, being found on the Shelf Edge Reef well offshore. The natural sand source and aggradation of beach is ephemeral over time. Natural conditions for nesting sea turtles would be ephemeral, which is the nature of the beach. Leatherback sea turtles were recorded in the past nesting when a wide enough beach would form. In general, conditions for nesting sea turtles, native birds, and native vegetation have been removed or are limited by human disturbance via residential, commercial, and recreational activities on/near the beach, including encroachment, clearing, lighting, and noise. The Corps survey and USFWS information indicate that the species and relative abundance of native sponges present provide a source of food for adult sea turtles. There are also extensive seagrass beds that were found to be providing a food source for the Antillean Manatee. 

What other alternatives were considered?  

This study assessed feasible long-term coastal storm risk management solutions (over a 50-year period) that included but were not limited to coastal armoring, nearshore and shoreline sand impoundment structures (e.g., breakwaters and groins), various sand nourishment designs (with and without structures as mentioned above), and non-structural management measures (acquisition). Artificial reefs and enhancement of natural reef structures were considered and are generally more successful when paired with beach nourishment.  The artificial reefs/natural reefs can help to alleviate wave energy, allowing sand from beach nourishment to stay on the beach more effectively.  This option was investigated early in the study – however, artificial reefs on their own will not ensure that sand will return or effectively stay in place. Coastal armoring is a measure that may exacerbate erosion around the study area, resulting in unwanted adverse impacts to adjacent shorelines. Additionally, when previously proposed, this was not supported by the local community or by DNER. Beach nourishment was thoroughly investigated as part of this study. The Rincón area has a very large, historical sand deficit, meaning a large quantity of sand would be required for initial construction (or paired with sand impoundment structures) and the project would require continuous maintenance. Modeling results showed that sand replenishment would be required approximately every 5 years, creating continuous direct and indirect impacts to the emergent, nearshore and offshore habitats over the 50-year project life.  

Why isn’t beach nourishment recommended?  

All feasible costal storm risk reduction measures were considered during this study. Beach nourishment in particular was thoroughly investigated as an alternative. Beach nourishment in Rincón is highly expensive and not an environmentally acceptable or sustainable solution. The Rincón project area has a very large, historical sand deficit meaning a large quantity of sand would be required for initial construction (or paired with sand impoundment structures) and the project would essentially require continual maintenance.   Groins, shoreline perpendicular rock structures, paired with beach nourishment were investigated and modeling results showed that together they would hold sand in place for approximately 5 years before needing another periodic nourishment.  The continuous dredging operations needed to maintain the beach would adversely impact the emergent, nearshore and offshore habitats over the 50-year project life. The long-term, environmentally damaging effects of getting the sand from the offshore sand source paired with the high cost makes this plan not preferred, and therefore not recommended.  

What borrow sources were considered for the beach nourishment alternative? 

Numerous potential borrow areas (upland and offshore) were thoroughly investigated; however, none were found to have sufficient sand volume required for the project. As an example, Bajo Blanco was determined to not be a suitable borrow source due to the low volume of sand and since dredging may adversely impact local coastal hydrodynamics and the adjacent coastal resources such as the submerged resources and habitat within the marine preserve. The only suitable borrow area found is located approximately 30 miles south of the project area (Cabo Rojo), which is in close proximity to offshore marine resources and would be very expensive to dredge, transport and place the material along the beach. Nearshore and shore-connected coastal structures would also likely cause adverse issues to downdrift beaches by cutting off any sand supply that may currently exist in the area.  

What were the tradeoffs considered with other alternatives?  

All feasible coastal storm risk reduction measures were evaluated during this study for a 50-year period of analysis. After initial screening of alternatives, this study included a detailed evaluation of the following alternatives: 1. No action, 2. Rock armoring (revetment), 3. Beach nourishment (with and without coastal structures such as groins) and 4. Acquisition of coastal structures. The planning level cost estimate (during the plan comparison phase) for acquisition was estimated to be $110M, which was close to the cost of rock revetment (~$110M) and less than a beach nourishment and groin plan (~$194M). Since that time, the cost of acquisition has been refined, and is currently ~$140M. This is still less costly than a beach nourishment/groin project, and while the beach nourishment project would involve impacts to the nearshore and offshore habitats and potentially species, the proposed acquisition plan would generally increase critical upland habitat with little to no nearshore or offshore impacts. From a benefit-to-cost ratio (BCR) perspective, the recommended plan has a 0.20 BCR (including recreation benefits), which means the federal government is paying $.80 to every dollar spent, in order to provide homeowners a means to get money back on their investments now before it is too late, and to begin the process of sustainable coastal management along this section of the Puerto Rico coastline. All other plans had a BCR well below this amount and did not provide the comprehensive benefits that this plan provides.  

What would be the expected impacts on Rincón's community and economy without the recommended plan?  

In the absence of a plan, homes along the coastline in the identified areas are expected to be completely lost to the ocean and/or condemned due to safety reasons as a result of erosion, likely resulting in significant loss to associated homeowners. Under such devastating circumstances, property owners will likely experience significant financial losses and may be required to relocate due to structural instability of homes. Once homes are damaged to the point of being condemned, homeowners may not be able to receive compensation for their homes, or assistance to relocate.   Further, large portions of the beach will be inaccessible due to the resulting safety issues with the remnants of the destroyed structures, further impacting the limited environmental resources and recreational areas.  Structures would become derelict if not removed, which would further exacerbate wave energy, resulting in increased erosion to the surrounding shorelines.  

What would be the expected impacts on Rincón's Community and Economy with the recommended plan? 

This plan will afford homeowners with structures most at risk to erosion, the time and incentive to relocate in a coordinated effort before structural failure of homes occurs in a piecemeal fashion. The newly established, publicly accessible shoreline will function as a natural buffer, allowing time and physical space for Puerto Rico government entities to sustainably manage the shoreline and increase coastal resiliency into the future. The sandy shoreline would support the tourism-based regional economy into the future by maintaining $3,372,000 each year (over a 50-year period of analysis) worth of local tourism spending. The plan does not require mitigation but would instead accrue 4.14 average annual habitat units for shoreline species (such as nesting sea turtles, shoreline birds, native dune plants, insects and other small animals) within the acquisition footprint (creating 17 acres of beach habitat). This plan improves several social factors, including health and safety, social vulnerability and resilience, community cohesion and cultural identity by allowing the community of Stella to thrive with the renewal of a beach and removal of unsafe and unsightly structures, stopping and reversing the spread of decline in the community. This plan allows the southern part of Rincón to remain connected culturally and economically to the northern part of Rincón.  

How will the shoreline be managed after the recommended plan is implemented? 

The responsibility of future action to manage the shoreline will be with DNER.  The future erosion rate is dependent on many variables.  For example, the erosional trends in Rincón could continue as they historically have with seasonal and short-term shifts in the shoreline change rate as well as potential future impacts associated with sea level change. The removal of existing coastal structures and armoring could also reduce the historical erosion rate and allow the coastal system to naturally recover following erosional events.  The study used coastal modeling results to predict timelines and thresholds for DNER to manage the shoreline.  It is strongly recommended that DNER with the support of the local Rincón municipality monitor the shoreline erosion using the guidelines as recommended in the study and enforce no construction in the newly established coastal zone, to allow coastal processes to occur naturally and provide resilience to the community. 

Is this plan in line with the administration’s priorities for coastal resilience?  

This plan is consistent with Executive Orders and Administration priorities of coastal resilience. This plan is also in line with the coastal resiliency initiative as outlined in the Governor of Puerto Rico’s Administrative Bulletin Number OE-2023-009 (11 April 2023).  

Did the study consider local canal contributions to erosion?  

This study analyzed all existing coastal modeling, coastal engineering, and other reports as a part of the background data collection procedure. Federal coastal storm risk management feasibility studies are scoped to include cross-shore change modeling and economic modeling as detailed in Appendix A (Engineering) and Appendix D (Economics). Large river outflows that impact the study area were considered as a part of the existing documentation review and potential erosion/accretion concerns. Quebrada Los Ramos is the canal that drains the area’s upland watershed and was assessed during this study. Other aspects that relate to existing condition problems and potential future with-project performance, such as smaller local drainage outfalls or canals, were also considered during the feasibility process. Of note, there is no current data that supports or indicates that the Quebrada Los Ramos canal or any other canals are the main cause of beach erosion within the study area. 

Why weren't the areas with homes already affected by erosion (further south) included in the recommended plan? 

This plan will be most effective if a large swath of land is achieved to be used as a beach/buffer for natural coastal processes.  Farther south, there are some isolated structures that would not contribute to the continuity of this project. There were condominiums that were excluded due to the large cost of buying out all residents and the relatively small shoreline segments. Further, those condominium units appear to have large-scale seawalls installed that would provide increased protection to the upland properties. The plan assumes those coastal protection measures and properties would continue to be managed by the condominium owners and/or associations. 

What happens next? 

As of this time, the feasibility study is expected to be completed in June 2024 with a Chiefs Report.    Following the completion of the feasibility study in June 2024, if funding is appropriated by Congress, the proposed project could potentially move forward to the next phase which is pre-construction, engineering and design (PED). During the PED phase, which is prior to construction, the team would conduct shoreline surveys, collect additional data, and work with the community to help to refine the footprint for the project to the minimum extent practicable.  In order for the project to move forward into construction, the project would need to be both authorized in a Water Resources and Development Act (WRDA) and have funds appropriated by Congress.