Loading...
LTC 567-2019 King Tide Season SummaryMIAMI BEACH OFFICE OF THE CITY MANAGER NO. LT G # 567-2019 LETIER TO COMMISSION TO : Mayor Dan Gelber and Members o DATE : October 24, 2019 SUBJE CT: King Tide Season Summary Reducin rg f lood risk is of high importance to residents, as demonstrated in the resident survey a1nd an important priority of our strategic plan. I'm pleased to share that we are now ho Miing all-hands on deck after-action reviews for any type of event that may cause types offl ooding as a result of extreme rainfall, high tides, or storms. This is especially importa111t considering Miami Beach's low topography and sea level rise projections. An afte r-·<a ction review is a usefut fact-based analysis to understand and document conditions, what went welt and recommendations for improvement. By understanding the environmental conditions and areas of impact, we can better assess the effectiveness of our resilience efforts ranging from public infrastructure improvements to land use amendments. Staff presented an overview of the May 17, 2019 heavy rainfall event at the Septem b(er 26, 2019 Sustainability and Resiliency Committee (the item had been deferre d! f or a few months). Staff was prepared to discuss the most recent King Tide summa r y f or Item R9 I on the October 16, 2019 City Commission agenda; however the item wa s deferred. Attachment 1 includes the presentation that was prepared for Item R9 I. In sum m ar y: • li cle s were about a foot higher than predicted, reaching 2.18 feet on Oct. 1 and ne aching 1.5 feet or higher the rest of days (Sept. 26-0ct. 3). • Al l stormwater pumps worked effectively. In areas of low elevation (not yet imp roved) temporary pumps were deployed to alleviate flood risk where possib l e. • Th e ar eas that were affected the most by this event were: Indian Creek, North Bay Road, North Beach and Commerce Street . • 18 flood/drainage requests were made to the Public Works control room. • Approximately 200 standing water/flooding events captured by staff through Crisis Track (our emergency management tracking system) on Sept. 30. The city has further categorized flooding types for better analysis, and they include: o 71 standing water (minor puddle or standing water that do not present a risk to pedestrians, property owners or vehicular traffic) o 80 significant standing water (partial roadway blockage that presents inconveniences to pedestrians and vehicles. Reasonable drainage time frame expectedL and o 45 stormwater flooding (causing a complete obstruction of vehicular and pedestrian traffic on one or more low-lying streets in addition to impacting low-lying properties). This is comparable to the NOAA minor or moderate flooding definitions. NOAAINOS/CO..OP S Observed Water Levels at 8723214, Virginia Key, Biscayne Bay FL From 2019/09/26 00:00 LSTILDT to 2019/10/03 23:59 LST/LDT 4.0 .--------------------------------,4.0 3.0 6 2.0 ~ -1.0 ~ ~ 0.0 , .c C) ~ -1.0 -2 .0 00:00 9 /26 -2.0 NOAA NOS Center t oT Operational Ocunogra phlt Products-a.'nd Services 0000 9 /27 00:00 9 128 0000 9 /29 00:00 9 30 -Predictions -Verified -Observed -Forecast Guidance 00:00 10/1 oo·oo 1012 oo·oo 10/3 • Staff is now assessing results for completed and active projects, both visually and through data. In all areas of complete or nearly completed projects, no King Tide flooding was observed. In Sunset Harbour, 31 potential tidal flooding events have been avoided to-date to 2019. Avoided flooding is an assumption made by using data comparing tidal gauge data, the former road elevation, and the raised road elevation. Photos are included in the attachment. • Staff will also begin assessing vulnerable neighborhoods that have not had public infrastructure improvements during King Tide events going forward. • We are not aware of any private property damage . The review was organized by the CRO team, true to the role of convening and supporting operations from all departments to address our shocks and stresses. The review was led by the City Manager, with participation of Assistant City Manager, Public Works Engineering and Operations, Capital Improvement Projects, Emergency Management, the Building Floodplain Manager, Planning, and Communications. Attachment 2 contains the presentation used to facilitate the after-action review. Staff is using the best data available-ranging from the city's tidal gauges to complaints from the control room, to monitoring inspections conducted by staff, with a spatially based analysis supported by GIS. The team is combining multiple automated data systems in a utilizing a Power Bl dashboard funded with seed money from Bloomberg Philanthropies competition. This analysis will allow us to better understand and respond to events-to connect the dots. Ultimately, the documentation and coordination will help provide the Commission information needed to make policy-level decisions. I am very pleased with the collaboration among departments and the collection of actionable and practical data to inform future decision making. If you have any questions, please contact Susanne Torriente, Assistant City Manager/Chief Resilience Officer, or Amy Knowles, Deputy Resilience Officer. Attachment 1-King Tide Photo Presentation Attachment 2-King Tide After Action Presentation JLM/SMT/AK PUBLIC WORKS DEPARTMENTPUBLIC WORKS DEPARTMENT PUBLIC WORKS DEPT Before & After Elevation and Drainage Improvements Side-by-Side Comparisons October 16, 2019 PUBLIC WORKS DEPARTMENT << 2 >>Flood Mitigation Results Purdy Ave and Dade Blvd AFTERBEFORETides: 1.27 ft NAVD | 10/11/11 Tides: 1.88 ft NAVD | 10/15/19 PUBLIC WORKS DEPARTMENT << 3 >>Flood Mitigation Results Purdy Ave and 20th Street BEFORE Tides: 1.27 ft NAVD | 10/11/11 Tides: 1.88 ft NAVD | 10/15/19AFTER PUBLIC WORKS DEPARTMENT << 4 >>Flood Mitigation Results Purdy Ave and Dade Blvd BEFORE Tides: 1.27 ft NAVD | 10/11/11 Tides: 1.88 ft NAVD | 10/15/19AFTER PUBLIC WORKS DEPARTMENT << 5 >>Flood Mitigation Results Purdy Ave -North of Dade Blvd BEFORE Tides: 1.88 ft NAVD | 10/29/12 Tides: 1.88 ft NAVD | 10/15/19AFTER PUBLIC WORKS DEPARTMENT << 6 >>Flood Mitigation Results Purdy Ave -South of 18th Street BEFORE Tides: 1.27 ft NAVD | 10/11/11 Tides: 1.88 ft NAVD | 10/15/19AFTER PUBLIC WORKS DEPARTMENT << 7 >>Flood Mitigation Results 18th Street and Bay Road AFTERBEFORETides: 1.27 ft NAVD | 10/11/11 Tides: 1.88 ft NAVD | 10/15/19 PUBLIC WORKS DEPARTMENT << 8 >>Flood Mitigation Results Palm Island 316 South Coconut Ln BEFORE AFTERTides: 1.4 ft NAVD | 10/17/12 Tides: 1.88 ft NAVD | 10/15/19 PUBLIC WORKS DEPARTMENT << 9 >>Flood Mitigation Results Palm Island 303 North Coconut Ln BEFORE AFTERTides: 1.4 ft NAVD | 10/17/12 Tides: 1.88 ft NAVD | 10/15/19 PUBLIC WORKS DEPARTMENT << 10 >>Flood Mitigation Results West Ave and 6th Street BEFORE AFTERTides: 1.4 ft NAVD | 10/17/12 Tides: 1.88 ft NAVD | 10/15/19 PUBLIC WORKS DEPARTMENT << 11 >>NOAA Water Elevations Virginia Key, Biscayne Bay AFTER 10/15/19 PUBLIC WORKS DEPARTMENT << 12 >>Avoided 60 Tidal Flooding Incidents Due to Road Raising January 2017 -Present July 2017 Jan 2018 July 2018 Jan 2019 Jul 2019 Wa t e r L e v e r i n F e e t King Tides Review Sept. 26-Oct. 3 Oct. 17 2019 Public Works Department City Manager’s Office-Resilience Summary 1. The City of Miami Beach experienced King Tides from Sept. 26 to Oct. 3. 2. The stormwater system functioned as expected during this event, but higher than normal high tides caused minor flooding or standing water in some areas. 3. The areas that were affected the most by this event are: Indian Creek, North Bay Road, North Beach and Commerce Street. 2 Observed Water Levels -NOAA Oct 1. -levels reached 2. 18 feet (NAVD) •All days reached NOAA’s threshold of minor flooding. •Some days reached moderate flooding. 3 Observed Water Levels –Miami Beach Tidal Gauges •Miami Beach tidal gauges indicate a maximum tidal level of 2.25 feet NAVD on Oct. 1. •This graph shows that we avoided eight tidal flooding events due to road raising in Sunset Harbour during Sept. 26-Oct. 3. •2017: 17 events avoided •2018: 11 events avoided •2019: 32 events avoided 4 Flood Extent & Impact 1. Tides were about 1 foot higher than predicted, reaching 2.18 feet on Oct. 1 and reaching 1.5 feet or higher the rest of days (Sept. 26-Oct. 3). 2. Approximately 200 standing water/minor flooding events captured by staff through Crisis Track on Sept. 30. 3. 18 flood/drainage requests captured through control room and CityWorks. 5 18 Flood/standing water related complaints from Cityworks (includes EGov and phone calls to the Public Works Control Room) 6 Crisis Track Standing Water/Flood Events Reported (Sept. 30) •71 Standing water •80 Significant standing water •45 Stormwater flooding 7 4580 N. Bay Road, Miami Beach FL 33140, Sept. 27 at 9:27am 8 Indian Creek, Sept. 28 9 Collins Ave, Indian Creek and Jefferson Ave., Sept. 28 and 30, morning Flooding in Sardinia during peak hour. 10 Royal Palm Ave, Alton Rd. and N Bay Rd, Sept. 30, morning and noon Flooding in Sardinia during peak hour. 11 3250 Chase Ave., Sept. 30 12 Indian Creek., Oct. 1 13 Rue Notre Dame, 45th Street and N. Bay Rd, Oct. 1-2, afternoon 14 Mid-Beach and North Beach Oct. 1-2, early afternoon 15 34th Street and Garden Ave, Oct. 2 16 Sunset Harbour, Oct. 2 17 Sunset Harbour, Oct. 2 18 Sunset Islands, Oct. 15 19 Impact From King Tides Event Traffic congestion in the following areas: 1. Indian Creek Drive 2. Collins Avenue No business closures or road closures. No damage to fleet. Private properties and roads experienced standing water, significant standing water and stormwater flooding. 20 Standing Water/Flooding in Completed or Active Projects Sardinia at 1:17 pm – water cleared on the outside area. 1.Sunset Harbour 2.Sunset 3 and 4 3.Venetian Islands 4.Palm and Hibiscus 5.Indian Creek, 25TH –32ND St 6.Lower North Bay Rd. Did these neighborhoods experience standing water/ flooding? 21 Action: Will monitor according to SOP , going forward Standing Water/Flooding in Neighborhoods Requiring Monitoring Sardinia at 1:17 pm – water cleared on the outside area. Did these neighborhoods experience standing water/ flooding? Discussion Action: Will monitor according to SOP , going forward 22 1.North Beach 2.Central Lower North Bay Rd 3.Central Bayshore 4.Central Bayshore South 5.Lakeview 6.Orchard Park 7.Palmview Response to King Tides Event From Staff Public Works: 1. Used temporary pumps to alleviate flooding 2. Checked pumps 3. Responded to complaints 4. Communicated with businesses and residents 5. Documented flooding/standing water CIP: 1. Documented construction projects 2. Checked construction sites 3. Checked that pumps were operational Emergency Management: 1. Communicated tidal levels internally 2. Checked weather updates to monitor NWS advisories 3. Worked with Public Works to create Crisis Track event Communications: 1. Sent social media and email updates about event 2. Advised the public to report flooding/standing water to control room 3. Documented standing water/flooding 23 Develop an approach to documenting conditions and how improvements are working. Flood Documentation Procedure (DRAFT) discussion 24 Residents/ Employees Employees Neighborhood Infrastructure Projects Future Neighborhoods (low-lying) Social Media Private Property Damage Estimated Resources & Costs 25 Public Works Operations (Yard): •Total of 15 people worked during event •Equipment used: vactor trucks, temporary bypass pumps, pick-up trucks, fuel trucks •Estimated value of temporary bypass pumps: $36,560 •Estimated value of fuel for temporary bypass pumps: $3,656 •Estimated value of labor & equipment such as vehicles and vactor trucks: $15,000 Recommendations 26 Create a GIS map of planned, completed and in-progress stormwater projects. (pending) Discuss changes to City Code that may require higher elevation and/or an commercial property owner (Nov SRC). Utilize employees already in the community (PWD, Code, Police) to take photos. (in draft SOP) Coordinated approach in using systems to avoid repetition of data and efforts.(in draft SOP) Develop plan for tracking and monitoring after-action recommendation. (complete) Update the Flood Response Preparedness & Communication Standard Operating Procedure (in draft SOP) Conduct routine after-action meetings to understand what went well and what needs improvement. (underway) Train staff on using control room as a central point for communicating and addressing flood complaints. (complete) Event Review What went well during event? discussion What are potential opportunities for improvement? discussion 27 Sources 28 •Crisis Track photos, drone imagery and flood events data. •CityWorks requests and work orders related to standing water/flooding. •Photos from Public Works Operations and Communications. •Narratives and input from Public Works, Communications, CIP and Emergency Management. •Data can be found in the M drive: M:\$CMB\Resiliency_Strategy_Team under “Miami Beach 2019 Rain and King Tides.” Thank you 29