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    • NOAA Water Levels for Coastal, Estuaries and Great Lakes regions

    Metadata Updated: September 30, 2025

    For over 200 years, NOAA's Center for Operational Oceanographic Products and Services (CO-OPS) and its predecessors have been managing a comprehensive system for observing, communicating, and assessing water levels nationwide, including on the Great Lakes, and in certain U.S. territories. The standard data collected from our water level stations are reported in 6-minute intervals, and support the National Water Level Observation Network (NWLON), short-term Vertical Datum (VDatum) Projects, the National Tsunami Warning System, the Physical Oceanographic Real-Time System, or PORTS Program, and other partnerships. These data are quality controlled and used to support safe and efficient maritime commerce, sound coastal management, recreation, and studies in sea level and climate changes. The secondary datasets derived from these observations are highs and lows (except for Great Lakes), hourly heights, daily means (Great Lakes only), and monthly means, from which all other CO-OPS datasets are derived for datums, tidal predictions, and sea level applications. Hourly heights in particular are utilized to calculate historic high tide flooding statistics, and to compute monthly mean sea level values, which are incorporated into tidal datums for nautical charting and harmonic constituents for generating tidal predictions. Note: both products of high tide flooding statistics and tidal predictions are calculated on the fly and are not stored, nor considered as data.

    Access & Use Information

    License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

    Downloads & Resources

    Dates

    Metadata Date September 24, 2025
    Metadata Created Date October 31, 2024
    Metadata Updated Date September 30, 2025
    Reference Date(s) 1835 (creation), (publication)
    Frequency Of Update biennially

    Metadata Source

    Harvested from NOS CO-OPS

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date September 24, 2025
    Metadata Created Date October 31, 2024
    Metadata Updated Date September 30, 2025
    Reference Date(s) 1835 (creation), (publication)
    Responsible Party (Point of Contact, Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:64567
    Access Constraints Cite As: Center for Operational Oceanographic Products and Services, [Date of Access]: NOAA Water Levels for Coastal, Estuaries and Great Lakes regions [Data Date Range], https://www.fisheries.noaa.gov/inport/item/64567., Access Constraints: None, Use Constraints: Preliminary (raw) data have not been subjected to the National Ocean Service's quality control or quality assurance procedures and do not meet the criteria and standards of official National Ocean Service data. They are released for limited public use as preliminary data to be used only with appropriate caution. Historical data are only good for observations and may not reflect present day conditions. These data are only representative of the geographic location of the observation., Distribution Liability: Raw data have not been subjected to the National Ocean Service's quality control or quality assurance procedures and do not meet the criteria and standards of official National Ocean Service data. They are released for limited public use as preliminary data to be used only with appropriate caution.
    Bbox East Long 180
    Bbox North Lat 71.4
    Bbox South Lat -54.8
    Bbox West Long -180
    Coupled Resource
    Frequency Of Update biennially
    Harvest Object Id 67223479-42e1-4ff4-bc0b-0e44ff9f7066
    Harvest Source Id 217272a2-c20f-4b9e-a0e1-e42a6d539971
    Harvest Source Title NOS CO-OPS
    Licence NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
    Lineage Data are recorded and transmitted; then go through a quality control procedure and are loaded into a database.
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-180.0, -54.8], [180.0, -54.8], [180.0, 71.4], [-180.0, 71.4], [-180.0, -54.8]]]}
    Progress onGoing
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1835

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