3301 Rickenbacker Causeway, Miami, FL 33149

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1 Virginia Key and Miami Beach 2016 King Tide Report and Projections (to 2045) using: 3301 Rickenbacker Causeway, Miami, FL *THIS REPORT IS PROVIDED SUBJECT TO THE COASTAL RISK CONSULTING, LLC, PRINTED DISCLAIMERS AND TERMS WHICH ARE ATTACHED TO THIS STUDY AND WHICH ARE POSTED AT THIS ANALYSIS IS FURNISHED AS IS FOR THE PERSONAL USE OF THE CONSUMER AS OF THE DATE PROVIDED, IS APPLICABLE ONLY FOR THE ADDRESS OR ADDRESSES PROVIDED BY THE CONSUMER AND IS NOT TRANSFERABLE OR ASSIGNABLE TO ANY OTHER PERSON OR ENTITY.

2 Sea Level Solutions Day, which occurred on Sunday, October 16, 2016, was hosted by the Florida International University (FIU) Sea Level Solutions Center (SLSC) in Miami, FL. This event was designed to allow members of the community to participate in flood reporting and broaden their knowledge on climate change and sea level rise. FIU partnered with Vizcaya Museum and Gardens and the Climate Leadership Engagement Opportunities (CLEO) Institute for this event. The team provided citizen science kits to record maximum flood height during peak King Tide. Two representatives from Coastal Risk Consulting, LLC attended this event and participated in the group activities. One member, Renato Stella, was assigned to Miami Beach, while the other member, Alannah Irwin, was assigned to Virginia Key. Citizen scientists were checked in and appointed to different groups. The mission of this project was to increase public awareness of sea level rise and allowed citizens to see first hand the extent of King Tide at their designated location. Each group was given a kit consisting of a yard stick, a tape measurer, and a refractometer used to measure salinity. The groups were taught how to use the tools and then dispersed into their designated areas. Renato led a group of citizen scientists assigned to Michigan Ave and 11 th Street in Miami Beach. Between 9:30 AM EDT and 11:00 AM EDT, the group collected and analyzed multiple water samples, looking at water height and salinity content every 15 minutes. Major impacts of King Tide were not experienced at Michigan Ave and 11 th Street during the observation period. Based on historical records of flooding in this particular area, the observations did not seem correct. How was this possible? Looking for a reason behind this occurrence, Renato s group wandered a block north from their starting point at Michigan Ave and 11 th Street. They found 2.5 inches (0.21 ft) of standing water with salinity measures at 1 parts per thousand (ppt). A few blocks away at the next reference point, the water level was about the same, but the salinity was much higher at 20.5 ppt. These results are still surprising, but there is an explanation. Before answering these questions, it is important to analyze the other part of Sea Level Solutions Day., Alannah, the other CRC representative, was assigned to the Virginia Key group. Her group was given a few reference points, but given the limited time frame, they were only able to take measurements at the Marine Stadium and surrounding areas, with post-peak measurements at Hobie Island. The highest point of the King Tide occurred at 9:47 AM EDT and these data were captured at the marina between the Marine Stadium and the Atlantica Seafood Restaurant and Market on the Rickenbacker Causeway. Before the peak of King Tide (9:20 AM EDT), water measurements were found to be 19 inches (1.58 ft). This was demonstrated as flooding along the marina. The image on the next page, taken by Alannah, shows the flooding along the northern side of the marina adjacent to Atlantica Seafood Restaurant and Market. A marina patron approached her group and discussed the severity of the flooding. He explained that normally, the white poles (located at the bottom of the picture) are never submerged. He further explained that patrons will usually walk beyond the poles to remove or place their boats in the water. This narrative illustrated the degree of the flooding and the seriousness of adaptation. At the peak of King Tide, at 9:47 AM EDT, the flooding at the poles was measured to be 20 inches (1.67 ft). The distance from the poles to the edge of the boat ramp measured to be 36.5 feet. albertslap@coastalriskconsulting.com 7951 Southwest 6th Street, Suite 112, Plantation, FL Coastal Risk Consulting LLC 2

3 Salinity of 20.5 ppt at the pump station Observed flooding along the white poles at the norther section of the Rickenbacker Marina on Virginia Key, adjacent to the Marine Stadium. Picture was taken by the CRC Representative, Alannah Irwin, standing at the shoreline 36.5 feet away from the pole. 3

4 Separately, CRC had another employee, Mark Rochelo, recording independent observations of peak King Tide along Miami Beach. Mark was located on Highway A1A (Indian Creek Drive) at the Alden Hotel, between 29th Street and 30th Street. Peak King Tide heights were forecast to be 1-2 inches higher than normal. On average, a peak high tide on Miami Beach will be between 2.8 feet and 3.5 feet. The picture on the left shows the forecast effects of King Tide flooding in 2016, 2030, and The risk of tidal flooding with increased sea level rise is important to note, especially in a high risk area such as Miami Beach. This portion of Miami Beach near the Alden Hotel is located in the AE flood zone, meaning that it is a higher risk area within the 100-year floodplain. The picture on the right, taken by Mark, shows the actual flooding from King Tide There was no tidal flooding during this event. The property, which is located along Indian Creek, would normally experience tidal flooding, especially with the 1-2 foot anticipated increase during peak King Tide at 9:30 AM EDT on Sunday, October 16, Some water on the steps was present due to the rain event that had occurred prior to peak King Tide. albertslap@coastalriskconsulting.com 7951 Southwest 6th Street, Suite 112, Plantation, FL Coastal Risk Consulting LLC 4

5 The results found by Renato and Mark are almost identical. This is because, prior to the King Tide, Miami Beach implemented a series of portable water pumps to prepare for the flooding event. Renato discovered one of these pumps at Meridian Ave and 11 th Street and in this location, there was no significant flooding present. Mark found the exact same thing on A1A along the leading edge of Indian Creek (see page 13 for locations). These adaptive measures are what prevented a potentially costly disaster from manifesting in Miami Beach. These pumps not only kept water out of the streets, but it saved hundreds of thousands of dollars in property damage that could have resulted from the onset of peak King Tide flooding. Measures like this are what can help coastal communities become resilient and sustainable in a future with higher sea levels. albertslap@coastalriskconsulting.com 7951 Southwest 6th Street, Suite 112, Plantation, FL Coastal Risk Consulting LLC 5

6 To demonstrate the severity of the flooding that could have been at Miami Beach, the results at the Rickenbacker Marina will be used as a proxy. The flooding at this location is representative of the flooding that can occur at Miami Beach if proper adaptive measures are not taken. The marina is located on the southwest side of the island and was the closest of the two Virginia Key reference points to Miami Beach. The environment of the marina is similar to the interior coastline of Miami Beach, which allows for favorable representation. At King Tide 2016, the maximum height was measured to be 1.67 feet above normal. In a future climate with higher sea levels, this extent can go above and beyond the elevation of the terrain in this area. Using the U.S. Army Corps of Engineers (USACE) sea level projections, future King Tides will be modeled in this report to express the impact of future event flooding. In 2020, when taking into consideration the USACE projected sea level rise, the highest extent of the King Tide will be 1.93 feet. In 2035, this number will be 2.29 feet. In 2045, this will be 2.73 feet. This further expresses the need to take the proper adaptive measures to prepare for future flooding events. A sample FIRST Score has been attached to this document to display the risk of non-storm flooding in the Rickenbacker Marina. This will be used to support the risk of future sea level rise in Miami Beach. albertslap@coastalriskconsulting.com 7951 Southwest 6th Street, Suite 112, Plantation, FL Coastal Risk Consulting LLC 6

7 3301 Rickenbacker Causeway, Miami, FL

8 3301 Rickenbacker Causeway, Miami, FL Government Risk Categories Assessment THIS PROPERTY IS WITHIN THE FOLLOWING GOVERNMENT- DESIGNATED RISK ZONES: Flood Zone: AE Evacuation Zone: A ZONE X500 ZONE AE ZONE D ZONE C ZONE B ZONE X ZONE VE ZONE E ZONE A This property is located inside of the 100-year FEMA floodplain Predicted flood water elevations have been established Special Flood Hazard Area (SFHA): YES The entire property is located in a SFHA. National Flood Insurance Program s (NFIP s) floodplain management regulations must be enforced This property is located in evacuation zone A and is at risk of significant hurricane storm surge flooding in the event of a Category 1 hurricane or higher. Max Hurricane Storm Surge Heights 2016 and 2030 Hurricane Wind Speed (mph) 2016 (ft.) 2030 (ft.) Category Category Category The Property s Base Flood Elevation (BFE) 9 Feet above NAVD88 *These property-specific risk categories are further explained on pages

9 Flood Inundation Risk Score and Table (FIRST SCORE ) The FIRST Score is the TOTAL number of tidal flood days over a 30-year period as projected using modeling based on the US Army Corps of Engineers (USACE) high sea level rise projection (footnote) and other local factors. This property has a maximum total of 2289 tidal flood days over 30 years 3301 Rickenbacker Causeway, Key Biscayne, FL FIRST Score 2289 Date Range # Tidal Flood Days Risk Meter CUMULATIVE FIRST SCORE = 2289 The FIRST Score is broken down into six 5-year increments. Each increment indicates the number of tidal flood days the property will experience during that time period. For example, over the years 2036 to 2040 there will be 566 days of tidal flooding. The risk meter begins at orange, indicating a moderate to high risk of non-storm flooding from present to With the effects of rising sea levels, the flood risk gradually rises to a severe risk of flooding between 2026 and By 2045, the property will experience up to 246 days of tidal flooding. This will also increase the impacts of the King Tide flooding events yearly, with the maximum extent of the flooding height measuring at 2.7 feet in The USACE high projection for sea level rise is lower than high projections from National Oceanic and Atmospheric Administration (NOAA), the US Third National Climate Assessment, Intergovernmental Panel on Climate Change (IPCC), and other projections in the peer reviewed literature. See references on p. 10 for local sea level rise rates out to

10 Risk Meter Key # Tidal Flood Days Recommendation 151 and up Major adaptation* adjustments are recommended Take adaptation* actions Plan preventative measures to minimize flooding impact 0-15 little or no adaptation* *Adaptation Planning and preparation for future time horizons to prevent or reduce the impacts of flooding due to higher sea levels. Adaptation actions may include: Accommodation - Strategies which prevent flood damage through measures such as vertical elevation (raising) of structures or stormwater system improvements. Protection - Strategies including hard and soft structurally defensive measures such as beach nourishment, planting mangroves, and building seawalls. # OF TIDAL FLOODING DAYS PER YEAR Number of Tidal Flooding Days per Year: *Non-storm flooding* The number of days of tidal flooding remains the same each year, as shown in the graph. 10

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12 3301 Rickenbacker Causeway, Miami, FL Conclusions This region will experience increases in King Tide flooding with future sea level rise. The 2016 King Tide height extended to 1.67 feet above normal. The visual representation can be found on page 3 in the bottom center image. The picture was taken during the flood event at ground level by CRC representative Alannah Irwin. Using the 2016 value of the King Tide height at Rickenbacker Marina, future heights were modeled using sea level rise projections. In 2025, the King Tide height is expected to reach 1.93 feet, while it is expected to reach 2.29 feet and 2.73 feet in 2035 and 2045, respectively. By 2045, King Tide is expected to inundate the majority of the marina and adjacent low-lying areas, negatively impacting all regions of Biscayne Bay. The average elevation of the property at the marina is 2.9 feet above the North American Vertical Datum of 1988 (NAVD88, The range of land elevation within the property boundary varies from 0 to 6.4 feet NAVD88. The elevation data was based off of Florida Department of Emergency Management LiDAR data from Miami Beach has begun taking the proper adaptation measures to prepare for King Tide flooding. For this event, the city implemented portable pumps to keep water levels from reaching the heights found at Virginia Key. King Tide water heights from Meridian Ave and 11 th Street were measured to be 0.21 feet (page 3) due to the use of pumps in the area. The map on page 13 shows the location of the pumps along Indian Creek where the most significant flooding could have occurred. After this, Miami Beach is working to implement a permanent pump system which will greatly improve their ability to adapt and prepare for future sea level rise. The FIRST Score is a snapshot of flood risk. For a more detailed study, see the Coastal Risk Rapid Assessment. This comprehensive report provides an assessment of tidal/sea level rise, hurricane storm surge and heavy rainfall flooding with high-resolution maps indicating where, how deep, and when the flooding will occur. For further information, please contact us at (844) SEA-RISE ( ) or by at customerservice@coastalriskconsulting.com. 12

13 Location of Indian Creek Pumps during King Tide

14 REFERENCES The figure below illustrates a range of future local projections for sea-level rise (SLR), going to 2100 based on U.S. Army Corps of Engineers (USACE) estimates. These local rates apply the nearest tide gauge to the property which is considered for USACE relative SLR projections, located at Miami Beach, FL. The table on the right reflects the correlating SLR ranges in feet, from intermediate to high out to ( Year Sea-level Rise in ft ft ft ft ft ft The future rates of sea level rise may be higher than the USACE model predicts, and, therefore, the number of days of tidal flooding could be greater. CRC reserves the right to make adjustments to the flood likelihood estimates from time to time as it deems scientifically appropriate. 14

15 DEFINITIONS Evacuation Zone: Hurricane evacuation zones are areas of the city that may be inundated by storm surge or isolated by storm surge waters. Special Flood Hazard Area (SFHA): The land area covered by the floodwaters of the base flood is the Special Flood Hazard Area (SFHA) on NFIP maps. The SFHA is the area where the National Flood Insurance Program's (NFIP's) floodplain management regulations must be enforced and the area where the mandatory purchase of flood insurance applies. Storm Surge Zones: Hurricane storm surge zones are determined by the National Hurricane Center using ground elevation and the area s vulnerability to storm surge from a hurricane. Evacuation zones are based on hurricane storm surge zones. Flood Zone: AE PROPERTY SPECIFIC DEFINITIONS Zone AE is subject to flooding due to nearby bodies of water (lakes, rivers, canals etc.). Properties in this zone have a 1% chance of annual flooding therefore are part of the 100-year floodplain. Properties in zone AE are considered to be at high risk of flooding under the National Flood Insurance Program, therefore, flood insurance is required for all properties in this zone that have federally-backed mortgages. Areas in Zone AE have predicted water elevations above land for a 100-year storm event, known as the Base Flood Elevation (BFE). Construction in these areas must meet local floodplain zoning ordinance requirements, including evidence that the structures are above the BFE. Flood insurance rates in high-risk areas (Zone AE) are calculated based on a variety of factors, including elevation and building construction. Policies can be purchased for contents only, building only, or both contents and building coverage. Talk to a licensed insurance agent to determine the premium for your specific property. For more information on flood insurance policies visit this page. Evacuation Zone: A Please visit this page for further reference on evacuation zones. Special Flood Hazard Area (SFHA): YES, this property is in a SFHA What is a Special Flood Hazard Area (SFHA)? Land areas that are at high risk for flooding are called Special Flood Hazard Areas (SFHAs), or floodplains. These areas are indicated on Flood Insurance Rate Maps (FIRMs). In high-risk areas, there is at least a 1 in 4 chance of flooding during a 30-year mortgage. Please visit this page for more detailed information on SFHAs. 15