Bay Swimmers: Data Can Help Make Your Swim Safe and Speedy

Submitted by admin on 05/27/2014

As summer approaches and water temperatures warm, many area residents and visitors take to the water. While some relax in the water in a quick cooling dip, others test themselves in one of the area’s many competitive open-water swimming events or triathlons slated for the summer months. 

One of the larger open-water swims is the annual Great Chesapeake Bay Swim, during which participants swim 4.4 miles from Kent Island on Maryland’s Eastern Shore to Sandy Point State Park on the Western Shore. Because this course crosses the deep main channel up the Bay, it is often characterized by strong currents. To help event organizers maximize safety, NOAA provides information on tides and currents to help planners set the optimum starting time for the swim. 

Current forecasts developed by computer models are available thanks to CBIBS partner MARACOOS.

  • Simply visit assets.maracoos.org and zoom in to the area you’d like to see.
  • In the lefthand column, in the “Models” box, select only the “Chesapeake currents” option. The map will populate a computer-generated forecast of currents. You can move forward and backward in time using the “Change map date & time” arrows under the map. 
  • Another option is to click on a location on the map, creating a red “X” for the spot where you’d like a graph of computer modeled information. That graph—for 48 hours of current speed and direction—will appear in the “Time-Series Query Results” area.

NOAA weather forecasts and data on water temperature and other water conditions (including wave height) are also helpful as swimmers gear up for their big adventure. CBIBS buoys at the mouths of the Patapsco (SN) and Severn (AN) Rivers give swimmers and organizers a good look at what conditions on the course by the Bay Bridge are like, and participants can also create graphs to see what recent trends indicate. 

Many open-water swims and triathlons set a water temperature threshold above which wetsuits are not allowed, so tracking water temperatures via CBIBS buoys can be handy. Wetsuits are used in cooler water temperatures to keep swimmers warm. But wearing a wetsuit increases a swimmer’s buoyancy—and because the higher a swimmer is in the water, the less water resistance they encounter, resulting in a faster swim. The Great Chesapeake Bay Swim allows swimmers to wear wetsuits no matter what the water temperature is.

Keeping tabs on conditions and knowing the weather and current forecasts can help make your swim a safe and enjoyable experience. The NOAA CBIBS team wishes you all a great swim!