Surge, Wave, and Tide Hydrologic (SWaTH) Network in Maryland, Delaware, and the District of Columbia

Science Center Objects

Many U.S. Geological Survey Water Science Centers have responsibilities for coastal regions within their mission areas. The integrated Surge, Wave, and Tide Hydrologic (SWaTH) Network has been developed in the wake of Hurricane Sandy to support model development and verification for coastal regions, detection of hydrologic trends, and early warning of hydrologic hazards in the northeast from Virginia to Maine.

The integrated Surge, Wave, and Tide Hydrodynamics (SWaTH) network has been developed in the wake of Hurricane Sandy to support model development and verification for coastal regions, detection of hydrologic trends, and early warning of hydrologic hazards in the northeast from North Carolina to Maine, and will be used as a template for the remainder of the United States. 

Background

Many U.S. Geological Survey (USGS) Water Science Centers (WSCs) have responsibilities for coastal regions within their mission areas. The integrated Surge, Wave, and Tide Hydrodynamics (SWaTH) network has been developed in the wake of Hurricane Sandy to support model development and verification for coastal regions, detection of hydrologic trends, and early warning of hydrologic hazards in the northeast from North Carolina to Maine, and will be used as a template for the remainder of the United States. 

This mobile network consists of water-level and barometric-pressure monitoring devices that are deployed in the days and hours just prior to a potential widespread storm-surge event, and then retrieved shortly after event occurrence. The network also includes a smaller number of Rapid Deployment Gages (RDGs), which are temporary water-stage sensors with autonomous data-transmission capacity. RDG’s are set up in advance of an event to provide short-term water-level and meteorological data during the event for areas that are particularly vulnerable to the effects of storm surge.

Objectives

The deployment and data-collection goal of the SWaTH Network is to:

(1) maximize the deployment of temporary storm surge and wave sensors within a network of pre-established locations,

(2) establish wave-monitoring sensors along pre-selected transects that extend inland through various physical features from shore to built-up environments,

(3) increase capability to deploy real-time monitoring gages at locations critical to emergency managers, and

(4) provide as much hydrologic data as possible to accurately define the scope and timing of storm tide, surge, waves, and inland flooding associated with hurricanes, intense Nor’easters, and any other areally-distributed surge-producing weather phenomena. By providing a standardized set of equipment and procedures, it is hoped that increased efficiency, accuracy, and equipment survivability will be realized while producing spatially-distributed data for immediate and long-term uses.

Approach

The installation of fixed brackets and reference points (RPs) for storm-based housing deployment at pre-selected locations in the SWaTH Network is needed to improve the USGS’s capability to deploy and recover sensors before and after storm events. Fixed bracket and RP deployment activities will include:

(1) proper site selection of existing and proposed sensors and gages, 

(2) securing any necessary site permissions or property-access agreements, 

(3) properly documenting sites with photos, sketches, and location information,

(4) installation of brackets and/or RPs at each location,

(5) determination of required sensor-housing lengths (as needed) for storm-based sensor deployment,

(6) surveying of vertical control at each location, and

(7) populating data into the Short-Term Network (STN) Mapper Application.

The SWaTH network in the Maryland-Delaware-District of Columbia Water Science Center (MD-DE-DC WSC) currently includes 52 sensor locations in Maryland, 31 sensor locations in Delaware, and 3 sensor locations in the District of Columbia, along with 5 RDG locations distributed across the region.

Data from previous sensor deployments for selected coastal storms from calendar years 2005 through 2012 are available online through the USGS Office of Surface Water Hurricane Storm Tide Sensor Map at: http://waterwatch.usgs.gov/hsss/index.php