PERFORMANCE OF RESIDENTIAL AND LOW-RISE BUILDINGS
Protective wall failure due to lack of tie-back rods to prevent seaward slumping of wall due to erosion
Beach erosion in Luquillo exposing sheet pile (red arrow) protecting road.
Current FIRM Unshaded Zone X
Current FIRM AE Zone, BFE 2.4 m
Advisory Data Shaded Zone X
Advisory Data AE Zone, BFE 2.4 m
Parking area behind house in Luquillo undermined by erosion Current FIRM VE Zone, BFE 4 m Advisory Data VE Zone, BFE 3 m
*Zones AE and VE are in the SFHA. Zone X is outside of the SFHA and represents an area of minimal flood hazard.
In addition to storm-induced erosion, Rincón has been experiencing long-term erosion and shoreline retreat (Thieler, Rodriguez and Himmelstoss 2007). The area also experienced significant erosion from hurricane Matthew in 2016 even though the storm tracked far to the south and west of Puerto Rico (Aponte-Bermúdez, et al. 2017). Figure 3-15 shows several aerial photographs taken over time. In the 1930s, there was a wide natural sandy beach and no development in the area. Since the 1930s, the area was developed and homes built. However, without consideration of the longterm erosion impacts, the buildings were built at an elevation and a distance from the water that were thought safe. Over time, that beach has eroded, leaving the homes at a greater risk to damage from coastal storms. Before the 2017 hurricanes, the beach in front of this building had already been eroded away, leaving the building vulnerable to undermining by storm surge and waves. As part of the Puerto Rico Advisory Data effort, long-term erosion rates were estimated, and 30-year and 60-year future shoreline positions were estimated (Figure 3-16). These Advisory products show areas, such as in Rincón, which are potentially subject to long-term and storm-induced erosion risks to guide smarter siting and design decisions.
HURRICANES IRMA AND MARIA IN PUERTO RICO
MITIGATION ASSESSMENT TEAM REPORT
3-19