Connecticut Sea Level Rise and Storm Surge Viewer Dataset

Brief Description:

This dataset shows different flood maps of storm surge return periods of 10, 30, 100, and 500 year flood events with sea-level rise projections (1 foot and 20 inches), above the North American Vertical Datum of 1988 (NAVD88) along the Connecticut coastline and the adjacent inland. CIRCA research recommends that planning anticipates sea level will be 20 inches higher than the national tidal datum in Long Island Sound by 2050.

Dataset Content:

The dataset contains two different datasets:

The Mean Higher High Water (MHWW) and 1 foot and 20 inches sea level rise layers
The modeled storm surge water levels using coupled coastal circulation and wave model (FVCOM-SWAVE) for The return period of the storm events is presented as 10, 30, 100, and 500 year flood events or 10%, 3.33%, 1%, and 0.2% annual exceedance probability storms, with and without the anticipated 20 inches of sea level rise.

Temporal Coverage:

The temporal coverage for the modeled dataset used 44 highest storms between 1950-2018 with 10%, 3.33%, 1%, and 0.2% annual exceedance probability storms.

Spatial Coverage:

The model domain covers the CT shoreline and is given as a polygon.

Update Schedule:

• Recently updated on June 2021
• Next update:

Usage Restrictions:

None

Detailed Description:

Two different sets of data are presented in the viewer. The Mean Higher High Water (MHWW) and 1 foot and 20 inches sea level rise layers are the modeled tidal water surface that has been created using VDatum (NOAA) and 2016 LiDAR topographic data. High probability areas of inundation are color shaded blue as well as low-lying areas, which are all shaded yellow. These low-lying areas need further evaluation due to the hydrologic complexity created by flood control structures, bridges, and culverts.

The second set of data, is the modeled storm surge water levels using coupled coastal circulation and wave model (FVCOM-SWAVE, finite-volume coastal ocean model with the version of the Simulating Wave Nearshore) to hindcast the 44 highest storms between 1950-2018. This model is calibrated for Long Island Sound to capture the complexity of Connecticut’s geology and landscapes and improve accuracy for effective flood risk design. The floodwater elevation for the different return periods is calculated empirically using a Poisson-GPD fit. The return period of the storm events is presented as 10, 30, 100, and 500 year flood events or 10%, 3.33%, 1%, and 0.2% annual exceedance probability storms, respectively. The anticipated sea level of 20 inches by 2050 is also added to these different flood events using the same data described in the paragraph above (2016 LiDAR topographic data). The vertical datum for all the datasets is NAVD88.

It is important to note that the 100 year flood event layer in this tool is different from FEMA’s 100 year flood map boundary for a few reasons:

The modeled data is calibrated for Long Island Sound to capture the complexity of Connecticut’s geology and landscapes and improve accuracy for effective flood risk design.
The FVCOM model has higher accuracy in predicting storm surge levels.
The FVCOM modeled data only displays storm surge while FEMA maps incorporate both surge and waves.

Wave-related splash over along the Connecticut shoreline requires smaller-scale resolution modeling. CIRCA continues to work on developing total water level flood maps that include wave data for the Connecticut coast and will update tools as new information becomes available.

Documentation:

Please reach the viewer from here.

Related File Naming & Structure Information:

Dataset Format and Size:

ArcGIS REST URL

Download:

To pull the data into your ArcPro account and explore it more on your own, do the following:

Open ArcPro and Start a “New Project”.
Under the “Map”tab, click the arrow next to the “Add Data” icon.
Choose the option “Data from Path”.
Insert the links below and click “Add” and the data and symbology will import into your map.

Note: Because the file is so large, it might take a couple of minutes for all the data to load into your map.

MHHW: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/MHHW/FeatureServer

MHHW and 20 inches of sea level rise: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/MHHW_20in/FeatureServer

MHHW and 1 foot of sea level rise: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/MHHW_1ft/FeatureServer

10 year return period of storm: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/slr10yr_doublecheck_union/FeatureServer

10 year return period of storm and 20 inches of sea level rise: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/100yr_connected_doublecheck_union/FeatureServer

30 year return period of storm: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/30yr_doublecheck_union/FeatureServer

30 year return period of storm and 20 inches of sea level rise: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/30yr_20inc_doublecheck_union/FeatureServer

100 year return period of storm: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/100yr_connected_doublecheck_union/FeatureServer

100 year return period of storm and 20 inches of sea level rise: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/100yr_20inc_conneceted_doublecheck_union/FeatureServer

500 year return period of storm: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/500yr_doublecheck_union/FeatureServer

500 year return period of storm and 20 inches of sea level rise: https://services1.arcgis.com/6ItOFXGFmdtfeOZb/arcgis/rest/services/500yr_20inch_doublecheck_union/FeatureServer

Citation:

For dataset source, please cite: Massidda, C., Liu, C., Jia, Y., Onat, Y., and O’Donnell, J. (2021) Connecticut Sea Level Rise and Storm Surge Viewer, (v.1), [Dataset], University of Connecticut, Connecticut Institute for Resilience and Climate Adaptation, Retrieved from https://resilientconnecticut.uconn.edu/resources/datasets/connecticut-sea-level-rise-viewer/ ‎Date Accessed:XX-XX-XXXX

Please note: If you acquire any data products from CIRCA, we ask that you acknowledge us in your use of the data. This may be done by including text such as “The data is provided by the UConn CIRCA, Connecticut, USA OR By citing the dataset in any documents or publications using these data.
We would also appreciate receiving a copy of the relevant publications. This will help us to justify keeping the data set freely available online in the future. Thank you!

Contact:

circa@uconn.edu

Data Disclaimer:

This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user. Attempts have been made to ensure that this data or documentation is accurate and reliable; The University of Connecticut, nor the Department of Marine Sciences, does not assume liability for any damages caused by inaccuracies in this data or documentation, or as a result of the failure of the data or software to function in a particular manner. The University of Connecticut, nor the CIRCA, makes no warranty, expressed or implied, as to the accuracy, completeness, or utility of this information, nor does the fact of distribution constitute a warranty.