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LTC 394-2017 Flooding ReportMIAMI BEACH OFFICE OF THE CITY MANAGER NO. LTC # 394-2017 LETTER TO COMMISSION TO: Mayor Philip Levine and Members of the City Commission FROM: DATE: August 3, 2017 SUBJECT: Flooding Report The following information is a summary of Tuesday's flooding events, immediate response activities, after actions to date and mitigation efforts going forward. This L TC also provides answers to questions we have received from Commissioners, residents, businesses and/or the media. EVENT SUMMARY Miami Beach experienced heavy flooding Tuesday afternoon. Advisories from the National Weather Service (NWS) at 2: 14 PM indicated heavy rains and forecasted minor flooding in Miami Beach with up to two inches of rain already fallen. By 3:45 PM NWS advised that between three to five inches of rain had fallen. Our records reflect a rate of more than nine inches per hour and an accumulation of 6.5 inches from 2:00 PM to 5:00 PM. (Attached please find rain totals for Miami Beach and other local jurisdictions from the NWS). While we mobilized flood teams throughout the city, we experienced a great amount of rainfall in a very short period of time, with no advance notice. This amount of rainfall is twice the City's, and most cities', design criteria for storm water infrastructure. Unfortunately, we also experienced power outages in the city; the FPL website indicated more than 7000 outages county wide on Tuesday. These power outages caused some pump station electrical systems to be temporarily down. The city deployed emergency generators as needed. This storm highlighted the importance of our comprehensive program of raising roads and protecting our public infrastructure. We witnessed main arterial roads that were impassable; evacuation routes were flooded and public safety was impacted. We must continue our commitment to invest in and adapt our infrastructure for today and a resilient tomorrow. DAMAGE ASSESSMENT PHASE Yesterday seven Building Department inspectors assessed 59 properties. The inspections were carried out based on reports that came in from 73 locations, but it became apparent that some of the reports were duplicates or were simply for street flooding and not for property damage. Two Code Compliance Officers did assessments at 21 locations with reports of mostly minor damage. Staff is still compiling the information gathered. Preliminary assessments from our departments show more than 20 roof-damaged properties and several elevator pits damaged as well. An early estimate of more than $450,000 of damage at the Convention Center has been reported as well. STORMWATER DESIGN CRITERIA On the issue of the design criteria and capacity of the system, please know that cities do not design for the most extreme events. That would be very costly, rather unattractive due to the size of the necessary infrastructure and, as a seven square mile built-out island, the required infrastructure would adversely impact open public space. Yesterday was an extreme event with a rainfall rate of more than nine inches an hour and a total of six and one half inches from 2:00 PM to 5:00 PM. Our system can and does handle three inches an hour, hour after hour. A design for a five-year storm means it can handle seven inches in 24 hours, and the expectation and plan is that within 24 hours conditions are dry. Miami Beach actually designs for the high end of the five year storm. But at no point does the design guarantee that no flooding or ponding will occur during significant rain events. Rather, the commitment is to drain the streets as quickly as possible thereafter. The pump at 34th Street and Chase Avenue is a limited capacity old generation pump for injection wells that was retrofit with an outfall connection to bring relief during king tides last year. We are planning to bring significant improvements to the area South of 34th Street in the new Central Bayshore South project. We are evaluating whether to interconnect with 34th Street as part of that project or significantly reduce the area that this pump needs to service. Either way we spent much time at this location during the event and believe it was overwhelmed for a long time because it is trying to serve much too large a drainage basin. GENERATORS Many comments have been directed to the loss of power at certain pump stations. Of the 15 pump stations that have been built and installed under the current robust stormwater program, five of the pumps lost power for some period of time on Tuesday. This explains the flooding at Lower North Bay Road, 14th street and 17th street. The pump stations in Sunset Harbor lost power for about 45 minutes. Interestingly, the streets remained flood free despite that outage, but some businesses which are below the base flood level were impacted. Once the pumps regained power, the streets in Sunset Harbor were one of the first that were flood free. In those neighborhoods where the pumps did not lose power (e.g. Crespi Boulevard, West Avenue), there was minimal impact from flooding. In those areas where the city has yet to do any work (e.g. Flamingo Park neighborhood, Lower Bayshore), flooding was significant. Earlier this year, the City Commission authorized the purchase of two generators for Sunset Harbor only each generator costs approximately $500,000 and the dimensions are approximately 5' x 12' x 6' elevated to 2' above base flood elevation which is about 5' above the street. Staff has been negotiating specifications and price over the last few months with the selected vendor, but there still remained a difference in price of more than $200,000. In light of the experience on Tuesday, we will expedite the purchase now in August and expect a 90 day delivery and installation timeframe. At the September 13, 2017 Commission meeting, staff will present a plan for back-up generators citywide to include costs, size and neighborhood aesthetics and space considerations. This presentation will also include costs to purchase a full SCADA system for remote monitoring and control of our infrastructure to modernize the management of our new infrastructure investments. The City has deployed portable generators to some of the pumps stations, and more are being deployed to be on-site for faster startups in the event of further power outages. The smallest of these generators are about the size of a small truck (see figure 1) and are located very close to the pump stations' control center. l . . DOOSAN • • I SUNSET HARBOR Sunset Harbor's neighborhood stormwater mitigation improvements are almost complete, and performed very well. During the power outage prior to the portable generators being delivered, unfortunately, flooding was experienced by some of the businesses that are located below the streets. In at least some of these cases the flooding was exacerbated due to the private property roof drains emptying into the lower levels of the sidewalks (see figure 2). The City's engineers and operation staff are working to identify ways to further improve system performance. AVAILABLE FEDERAL/STATE ASSISTANCE On Monday July 31, 2017, Florida Governor Rick Scott issued a Tropical Storm Emily State of Emergency for 31 counties, with Miami Dade County included. The City is working with Miami-Dade County to collect and document any impacts to homes and businesses within their jurisdiction that experienced damage due to flooding caused by Tropical Storm Emily. The business community can report damages (insured and uninsured) in the State Business Damage Assessment Survey at: http://flvbeoc.org/index.php?action=bda . Businesses should select Tropical Storm Emily under the "Event/Incident". Miami-Dade could qualify for a Small Business Administration Disaster Declaration if we meet the threshold, which is 25 homes and/or businesses damaged or destroyed with uninsured losses of 40% or more. If we qualify for the threshold of a SBA Disaster Declaration, small businesses will be able to apply for financial assistance such as an Emergency Bridge Loan that provides short-term, interest-free working capital to businesses that have been physically or economically impacted by the storm. Additionally, and as a first action, any damage should be reported to their flood insurance agent. SUMMARY & CONCLUSION In summary the stormwater pumps effectively dried the roads faster than the existing older gravity system. And the pumps worked quickly after regaining power. Our system works at its design capacity and for our forecasted sea level-rise. Our system will not protect immediately during extreme and intense quick events like Tuesday's rain, storm surge or dangerous hurricanes. Because we are a low lying coastal community, from time to time and in extreme cases the water will take longer to subside and other protective measures are available to shelter in place or evacuate for our safety. An important message we have been sharing with businesses and residents is that we are all in this together. The City is an island and 93% of buildings in Miami Beach are located in a FEMA special flood hazard area. The City is diligently working to raise roads, install pumps and replace aging infrastructure to improve drainage. This alone will not eliminate risk. We urge residents and businesses to also do their part to protect themselves and their property. For businesses that are below base flood level and in low-lying and flood prone areas, this includes using protective measures, flood panels or even sand bags when heavy rainfall is expected. We also urge residents to not walk through or drive through flood waters for their own safety and that of their personal property. It is our goal that all of Miami Beach, whether public roads or private homes, is in the best position possible before, during and after potential flooding. The attached Flood Awareness Fact Sheet has been prepared and previously shared for the purpose of preparing residents and businesses before and during a flood, and how to handle after the event. Please feel free to share before the next event. Visit www.mbrisingabove.com and click on flood awareness for more information. Finally, after any rain event we remind residents and businesses to drain and cover to avoid water ponding and mosquito breeding. We will provide additional information as available. Attachments JLM/SMT F:lcmgr\$ALLISUSY\L TC's\Flooding Report\Flood L TC.doc MIAiVil-SOUTH FLORIDA National Weather Service Forecast Office http://www.weather.gov/miami National Weather Service Preliminary Report August l, 2017 Miami and Miami Beach Flood Event Synopsis: an elongated area of low pressure (trough) extended across South Florida on August ist. This along with daytime heating triggered a band of heavy showers and thunderstorms just off the coast of Miami-Dade County early in the afternoon. This band then redeveloped to the west over Miami Beach, Key Biscayne and Downtown Miami just after 2 PM and became nearly stationary, then redeveloped farther to the west and southwest across The Redland, Kendall, Palmetto Bay and Pinecrest. Rainfall totals of 4-6 inches were widespread in these areas, with isolated amounts of 7-8 inches. Virtually all of this rain fell in a three-hour period during the mid and late afternoon ending around 6 PM. Rainfall rates of 2-4" per hour were common, with these rates generally lasting for 2-3 hours. This in combination with high tide between 5-6 PM led to significant flooding in the Miami Beach and Brickell areas. Impacts (information gathered from a combination of sources including TV and print media, social media and survey by NWS meteorologists): Miami Beach: numerous reports of flood waters entering businesses, homes, apartment lobbies and parking garages. Water was 1 to 2 feet deep on streets in many areas of South Beach, including Purdy Avenue, West Avenue, Alton Road, Pennsylvania Avenue, Meridian Avenue, Collins Avenue, Washington Avenue and Indian Creek Drive. Numerous vehicles stalled in these streets and others across the city. -City of Miami: more than 10 businesses, stores and buildings in the vicinity of Mary Brickell Village had at least 1 to 4 inches of water inside their structures, based on water marks and accounts from store employees. This includes stores and businesses on SW 10th Street between S. Miami Avenue and SW 1st Avenue. SW 10th street was also closed for half a block due to deep water. -Rest of Miami-Dade County: no major impacts noted other than flooded neighborhood streets. (note: this weather event was not directly associated with Tropical Storm Emily, but as part of the trough which extended across South Florida. This is the same trough that spawned Emily early Monday morning July 31st in the northeastern Gulf of Mexico, which moved south to across South Florida by Tuesday, August 1st.) Select 24-hour Rainfall Totals ending at 8 AM Wednesday, August 2nd (data below considered unofficial except Miami Beach Golf Club) The Redland/Krome Ave & SW 200 Street (CoCoRaHS) 7.46" Miami Beach/Alton Road & 56th Street (CWOP) 7.19" Miami Beach Golf Club (NWS COOP) 6.50" Virginia Key (Miami-Dade DTPW) 5.25" Virginia Key/NOAA-AOML (CoCoRaHS) 5.18" Florida's Turnpike & SW 173rd Street (CWOP) 4.72" Palmetto Bay (CoCoRaHS) 4.44" Pinecrest/The Falls 4.03" Kendall/SW 136th Street & 127th Ave (Wunderground) 3.84" Virginia Key: Univ. of Miami RSMAS 3.74" Brickell Key (Miami-Dade DTPW) 3.68 Vizcaya Area (WeatherBug) 3.41" Miami/SW 25th Street & 27th Avenue (Wunderground) 3.33" Surfside (CWOP) 3.31" Pinecrest/SW 102nd Street and USl (Wunderground) 3.19" Marlins Park (WeatherBug) 2.61" Note on graphics below: radar estimates can be significantly far off from actual measurements. Rain gauges are considered "ground truth" and are typically more accurate than radar estimates. The graphics below are storm total rainfall estimates from the Key West WSR 88-D radar. The Miami WSR 88-D radar graphic is not included as it did not have a good handle on the rainfall totals for most areas and was biased too low. The graphics of radar totals help us to graphically see the general areas where the heaviest rains occurred. For estimating rainfall totals, we use the rain gauge data, and then fill in the gaps with the radar data to provide estimates of rainfall totals. 24-hour rain graphic from NWS Key West WSR 88-0 Radar with select rain gauge measurements included 24-Hr Quantitative PrecipUation Acwrnul:atto.n (inches.) Valid: Wed Aug 2, 2017 2:00 PM EDT 24-hour rain total graphic from NWS Weather and Hazards Data Viewer Acknowledgments: Andrew Hagen of NWS Miami contributed greatly to this report by compiling the rainfall data and creating the graphicsJ as well as conducting an informal flood survey in the Brickell area yesterday evening. 10 STEPSTo FLOOD AWARENESS 1. COASTAL CITIES FACE FLOOD RISK. 93% of properties on Miomi Beach ore located in a Special Flood Hozord Area, as mapped by FEMA. Miami Beach is reducing risk through elevating roods, a new stormwoter system, and new construction regulations to build higher. El 93% de las prapiedades de Miami Beach se encuentra en un Area Especial de Riesgo de lnundacianes, ta/ y coma lo indican las mapas de la Agencia Federal para el Mane;o de Emergencias (FEMA, par sus siglas en ingles). Miami Beach est6 reducienda el riesgo tomando medidas coma la elevaci6n de carreteras, un nueva sistema de recagida de aguas pluviales y nuevas narmotivos para edificar mos alto. 1 O. MIAMI BEACH IS HERE TO HELP. The Building Deportment offers free technical assistance to identify ways to reduce flood hazards. Coll 305.673.7610 to learn more. El Departamento de Construcci6n ofrece asistencia tecnica gratuita para identificor las maneras de reducir las riesgos de inundaci6n. Llame al 305.673.7610 para obtener mos informaci6n. 2. PROTECT YOUR PROPERTY WITH FLOOD INSURANCE. It's required by federally bocked mortgages. The City saves you 20%, or $6 million dollars annually, in flood insurance premiums through top tier performance in the Community Roting System (CRS). For more informotion, check Floodsmort.gov Esta requerida por hipotecas Financiadas con fondos federales. A troves def desempeno de nivel superior en el Sistema de Calificaci6n de la Comunidad (CRS), la Ciudad le ahorra un 20%, o $ 6 mil/ones de d6/ares anuales en primas de seguro contra inundaciones. Para obtener ---... m6s informoci6n, visite Floodsmart.gov 9. FINANCIAL ASSISTANCE 3. BE SMART IF YOU SEE FLOOD WATERS! Avoid driving through or coming in contact with flood waters. Make sure you ore tuned into Miami Beach social media ond local weather alerts. No circule con su vehiculo ni vaya caminando par areas donde haya inundaciones. Mantengase informado a troves de las redes socio/es y las alertas meteoro/6gicas locales de Miami Beach. MIAMI BEACH RISING ABOVE Relief is ovoiloble for properties that hove experienced damage. Learn more by contacting the Grants Office at 305.673.7510. 8. KEEP IT CLEAN! Alivio para las propiedades que hon sufrido donas. Puede obtener mos informaci6n poniendose en contacto con la Oficina de Subvenciones en el telefono 305.673.7510. Don't litter! Keep storm drains clear of litter and debris to prevent flooding and keep Biscayne Boy clean. Report issues to the free Miami Beach e-Gov opp or coll 305.604.CITY. No tire basura. Mantenga las desagiies limpios de basura y escombros para evitar inundaciones y no bole basura a Biscayne Bay. Reporte sabre los problemas a troves de la opp gratuita Miami Beach e-Gov o /lame al telefono 305.604.CITY. 4. KEEP YOUR HOME AND BELONGINGS DRY. Consider elevating important appliances, like washers and dryers. Chose materials, such as tile flooring as opposed to wood, that ore resistant to water damage. Ponga en alto los electrodomesticos importantes coma la lavadora y la secadora. Para los suelos o pisos eli;a baldosas en lugar de madera, ya que se trata de un material mos resistente a los donas causados por el agua. 7. HAVE A PLAN! SOUTH FLORIDA CAN EXPERIENCE FLOODING FROM HURRICANES AND KING TIDES Know your evacuation routes, and how to protect yourself and your loved ones. Canozca las rutas de evacuaci6n y fa manera de protegerse a usted mismo ya sus seres queridos. S. BUILD RESILIENTLY. Follow the Florida Building Code to reduce flood risk. An elevation certificate provides your property's elevations, and con potentially lower your insurance premiums. The City may hove these for properties built ofter 1995. Coll 305.673.7610 to learn more. Siga las normas def C6digo de Construcci6n de Florida para reducir el riesgo de inundaciones. Un certificado de elevaci6n do la altura exacta de su propiedad, y puede potencialmente reducir el costo de/ seguro contra inundaciones. Es posible que la Ciudad tenga estos certificados disponibles para propiedades construidas despues de 1995. Llame al 305.673.7610 para obtener mas informaci6n. 6. OUR NATURAL SYSTEMS PROTECT US AGAINST FLOODS. Beach sand dunes and vegetation, coral reefs, and green open areas ore natural flood barriers. Las dunas de arena y la vegetaci6n de las pfayas, los arrecifes de coral y las zonas verdes son barreras naturales contra las inundaciones. 07.26.17 WHAT TO DO BEFORE, DURING, AND AFTE A F OD. Miami Beach is a beautiful coastal community. Our sun kissed island is surrounded by the waters of the Atlantic Ocean and Biscayne Bay. Miami Beach is leading the way locally and nationally to reduce flood risk and we want you to be aware of flood risk from major rain events and storm surge. It is our goal that all of Miami Beach -whether public roads or private homes -is the best position possible before, during, and after potential flooding. BEFORE A FLOOD tc+l m ® @ D · 930/o of buildings in Miami Beach are located in a FEMA Special Flood Hazard Area. Understand your flood risk, know your flood zone, and consider obtaining an elevation certificate to evaluate your property flood risk. ·Make sure you are tuned into Miami Beach social media and local weather alerts. Report any flooding to the city via thee-Gov app or by calling 305.604.CITY. ·Locate your flood insurance policy to be ready in the case you may need to file a claim for damage. ·Protect your non-residential building with flood barriers. ·Elevate mechanical equipment and appliances, as able, if you anticipate that waters may enter areas such as your garage. ·Avoid parking your vehicle in low lying areas-move it to higher ground, such as a parking garage. ·Don't litter. Keep public storm drains clear. Report issues to the Miami Beach e-gov app or call 305.604.CITY. · Have a hurricane and flood preparation plan. Know your evacuation route. ·Contact the Building Department 305.673.761 O and Public Works Department 305.673.7080 for technical advice on how to reduce flood hazard. Turn this page over for more Information. e DURING A FLOOD ·Be smart if you see flood waters! Stay safe -avoid driving through or coming in contact with flood waters. Six inches of fast flowing water can knock you off your feet and less than a meter of water can float car. ·Flood water can be contaminated with sewage or other pollutants. There could also be hazards below the surface, like debris, that you cannot see. AFTER A FLOOD • ........ )i{·.o (r~ FEMA · Report any flood damage to your insurance agent. · Clean and disinfect everything that got wet. ·Wash your car, including the undercarriage, if it came in contact with flood waters. · Rinse landscaping if it came into contact with flood waters. ·Don't enter a flooded building until it's been cleared by local authorities. ·Take pictures of the damage. Document both the building and contents ·Mitigate while you repair-make changes to prevent the risk of water damage in the event of any future flood events. ·Stay Alert-Continue monitoring the status of a flood or high tide via social media, television or radio., report flooding to the City via thee-Gov app or by calling 305.604 CITY ·If your house is in a flood zone and is damaged and/or improved to an amount greater than 50% of its building market value, the lowest floor will have to be raised to meet the current elevation requirement. Call the Building Department at 305.673.761 Oto learn more. · FEMA financial assistance is available for repetitive loss and substantial damage properties. Call the Grants office at 305.673.7510 to learn more. MIAMI BEACH RISING ABOVE www.mbrisingabove.com