CNC Launches Community Flood Information System ahead of Hurricane Delta
October 6, 2020
As Hurricane Delta barrels towards the Gulf Coast, CNC Catastrophe and National Claims will deploy a Community Flood Information System (CFIS) to track the extent of flooding in coastal locations. Delta has blown up into a category-4 hurricane today with maximum sustained winds of 140 mph, as of the National Hurricane Center 200PM advisory. It is forecast to slam into the Yucatan Peninsula Wednesday morning, then move into the Gulf of Mexico as a major hurricane.
The CFIS project follows a successful project launch for Tropical Storm Beta in Texas last month. During Beta, CNC deployed four flood meters at flood-prone homes in Galveston and Sea Isle, Texas. The meters measured flood depth above ground and also above the North American Vertical Datum of 1988 (NAVD88), the scale used for most elevation certificates.
Converting all flood levels to a common datum, or vertical reference, enables for quick and accurate flood impact assessment. For example, residents who evacuated could compare local flood levels to the first floor elevation on their elevation certificate to find out if their home likely flooded. In coastal communities, where many vacation homes and rental properties exist, this system also provided valuable insight for people wanting to check the flood risk of their property from a distance.
The CFIS for Tropical Storm Beta relied upon citizen scientists reporting flood observations every three hours from flood meters installed at their homes. Beta did not threaten the project area with high winds, so many people in elevated buildings stayed home and provided regular updates. One couple, who were celebrating their 47th wedding anniversary, faithfully submitted flood photos every three hours- even at 3:00AM!
These real-time observations enabled CNC to create flood inundation maps that estimated the water depth above ground level in the community. These maps helped people assess the likeliness of flooding inside buildings in the project area.
As we deploy flood meters in coastal communities for Hurricane Delta, we are interested to find citizen scientists who would partner with us to help collect community flood data. Participants need to have an elevation certificate that was professionally surveyed so we can calibrate the flood meters.
As personal safety is top priority, we are partnering with observers who live in lower wind/ flood impact areas or who have already determined to stay through the storm for personal reasons outside of our project. We will also install one streaming flood meter that sends time lapse photos of flood levels from a GoPro device through the cellular network, making it possible to collect real-time flood data without an observer present.
This technology may provide the world with the first snapshot of Delta’s peak surge level if deployed in the location of highest storm surge.
We are most interested to collect data from locations that do not have a NOAA tide gauge, to help fill in the data gap. The locations listed below are of highest priority….if you live in one of these areas and would like to be involved, please reply to this post or email Hurricane Hal at firstname.lastname@example.org.
Vermillon Bay/ Cypremort Point, Louisiana
Houma/ Cocodrie, Louisiana
Mandeville/ Slidell (North Shore), Louisiana
Gulfport/ Biloxi, Mississippi
This project was made possible through a grant provided to CNC Catastrophe and National Claims from the Northern Gulf of Mexico Sentinel Site Cooperative, in partnership with Dauphin Island Sea Lab. These entities funded a project titled, Improving Flood Resiliency in Biloxi’s Economic Development Corridor, which constructed the first comprehensive flood history for Biloxi, while creating elevation data for more than 900 buildings in the city.
The project identified monitoring flood levels as a challenge because Biloxi does not have a NOAA tide gauge. The new CFIS project helps Biloxi and other cities in the region monitor flooding because the flood meters are mobile and easily installed anywhere along the Gulf Coast.