Jet Ski Provides Platform for Collecting Water Quality Data in Bay Studies
Jag Ski Deployed to Measure Hydrocarbons, Investigate Coastal Dynamics in Mobile Bay
By Steve Werblow Freelance Journalist Ashland, Oregon and Bret Webb Assistant Professor University of South Alabama Mobile, Alabama
et skis are no longer just for fun; they can also be platforms of opportunity for coastal research. The Jag Ski, a red-and-
white Kawasaki Ultra LX personal watercraft (PWC) designed by the University of South Alabama's Bret Webb, isn't built just for thrill-seeking, but for bathymetric surveying, multiparameter water quality sampling and water-velocity studies in the shal- low estuarine environment of Alabama's Mobile Bay. Mobile Bay, roughly 48 kilometers by 19 kilometers wide,
is a drowned river mouth estuary that receives an average fresh- water discharge of 1,800 cubic meters per second from several rivers, including the Mobile and Tensaw. The bay's average
depth is 3 to 4 meters, sliced through by a 12-meter-deep ship- ping channel. When the Deepwater Horizon oil platform exploded and
sank about 161,000 meters off the mouth of Mobile Bay in April 2010, the Jag Ski was used to study the movement of oil from the spill. The findings revealed the dynamics of the Mo- bile Bay estuary and the performance of structures designed to repair the barrier island at the mouth of the bay.
Jag Ski Equipment The Jag Ski was initially designed to study scour holes near
bridge foundations and study nearshore currents, as its size and maneuverability allow it to access study sites unreachable by most boats. It was then equipped to carry out bathymetric sur- veys in shallow areas and the surf zone. The PWC uses a River Surveyor M9, an acoustic Doppler
profiler (ADP) manufactured by SonTek (San Diego, California). The RiverSurveyor M9, designed to deliver velocity and direc- tion measurements from 6 centimeters to 40 meters depth, is also equipped with real-time kinematic GPS.
Lightweight, portable and with minimal draft, the Jag Ski collects high- resolution data, georeferenced with real-time, kinematic GPS, across the deep shipping channel and the broad shallows of Mobile Bay.
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