Cool water and weak currents are predicted for the 600 swimmers expected to push off from Sandy Point tomorrow in the 4.4-mile Great Chesapeake Bay Swim.
Forecasters from the National Oceanic and Atmospheric Administration, a squadron of small boats and 557 volunteers will be on hand to ensure that everyone makes it safely across the bay to Kent Island, organizers say.
Baltimore port officials have agreed to close the shipping channels so swimmers have nothing but the Bay Bridge and each other to watch out for.
Swim organizer Chuck Nabit expects pledges and cash sponsorships to raise $30,000 for the Central Maryland chapter of the March of Dimes and its Campaign for Healthier Babies.
What began in 1982 as a solitary charity stunt by swimmer Brian Earley has grown into a national event, Nabit said. This year 600 people, the maximum allowed, from 25 states will swim.
The race course threads between the twin spans of the Bay Bridge, at the narrowest portion of the bay. The swimmers will leave Sandy Point Park about 8: 30 a.m. and swim for Hemingway's Restaurant on Kent Island.
The trip should take the winners about 90 minutes. Average swimmers will need 2 1/2 hours.
The swim is never easy, but there have been especially difficult years.
In 1991, strong winds and tidal currents exhausted most swimmers and turned the event into a vast rescue operation. It happened again in 1992, when 283 of the 331 people who began the race had to be pulled from the water.
In 1993, scientists at NOAA's Chesapeake Bay Office and National Weather Service forecasters began helping to time the swim so that most of it occurs during slack tide, when currents are weakest. Since then, 94 percent to 97 percent of the starters have finished.
At 6: 30 a.m. yesterday, NOAA personnel using an Acoustic Doppler Current Profiler borrowed from the University of Maryland made eight passes across the bay. The instrument bounced sound waves off particles suspended in the water at varying depths, yielding a profile of currents. Readings were compared with published predictions.
"It appears that the current speed is running a little faster than predicted," about 1.2 knots to the north, said Todd Stiles, a NOAA environmental technology officer. He attributed that to "sustained southerly winds."
By race time tomorrow, the outgoing tide at the bridge is expected to have slowed to less than 0.5 knots, reaching slack tide at 9: 58 a.m. Swimmers will get more up-to-date current and weather forecasts just before the race.
Stiles said water near the bridge was nettle-free yesterday and about 68 degrees -- cooler than the 73- and 75-degree temperatures of the past two years.
Swimmers will be shepherded by the Chesapeake Paddlers Club, a kayaking organization. The Chesapeake Bay Powerboat Association will have 50 to 55 boats nearby to assist with rescues, if needed.
The Coast Guard and its auxiliary will have 15 vessels in the area.
Pub Date: 6/08/96