Inundation Mapping Tidal Surface - Mean Higher High Water

These data are a derived product of the NOAA VDatum tool and they extend the tool's Mean Higher High Water (MHHW) tidal datum conversion inland beyond its original extent. VDatum was designed to vertically transform geospatial data among a variety of tidal, orthometric and ellipsoidal vertical datums - allowing users to convert their data from different horizontal/vertical references into a common system and enabling the fusion of diverse geospatial data in desired reference levels ( However, VDatum's conversion extent does not completely cover tidally-influenced areas along the coast. For more information on why VDatum does not provide tidal datums inland, see Because of the extent limitation and since most inundation mapping activities use a tidal datum as the reference zero (i.e., 1 meter of sea level rise on top of Mean Higher High Water), the NOAA Office for Coastal Management created this dataset for the purpose of extending the MHHW tidal datum beyond the areas covered by VDatum. The data do not replace VDatum, nor do they supersede the valid datum transformations VDatum provides. However, the data are based on VDatum's underlying transformation data and do provide an approximation of MHHW where VDatum does not provide one. In addition, the data are in a GIS-friendly format and represent MHHW in NAVD88, which is the vertical datum by which most topographic data are referenced. Data are in the UTM NAD83 projection. Horizontal resolution varies by VDatum region, but is either 50m or 100m. Data are vertically referenced to NAVD88 meters.

Data and Resources

Additional Info

Field Value
Last Updated November 2, 2017, 21:53
Created June 19, 2017, 21:55
access_constraints ["Use Constraints: The dataset is provided as is, without warranty to its performance, merchantable state, or fitness for any particular purpose. The entire risk associated with the results and performance of this dataset is assumed by the user. This dataset should be used strictly as a planning reference and not for navigation, permitting, or other legal purposes.", "Access Constraints: None"]
bbox-east-long -64.510
bbox-north-lat 49.005
bbox-south-lat 17.619
bbox-west-long -124.851
coupled-resource []
dataset-reference-date [{"type": "publication", "value": "2017-01-01"}]
frequency-of-update asNeeded
licence ["Any conclusions drawn from the analysis of this information are not the responsibility of the Office for Coastal Management or its partners."]
metadata-date 2017-10-31
progress completed
resource-type dataset
responsible-party [{"name": "NOAA Office for Coastal Management", "roles": ["pointOfContact"]}]
spatial {"type": "Polygon", "coordinates": [[[-124.851, 17.619], [-64.51, 17.619], [-64.51, 49.005], [-124.851, 49.005], [-124.851, 17.619]]]}
spatial_harvester true
temporal-extent-begin 2007-10-01
temporal-extent-end 2017-09-07