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GLIN==> BEWARE OF CURRENTS AT GREAT LAKES BEACHES



NEWS RELEASE
For Release:   IMMEDIATELY
August 31, 1999


For More Information:
Jim Lubner, Marine Safety Specialist, (414) 227-3291
Philip Keillor, Coastal Engineering Specialist, (608) 263-5133


DON'T GET CARRIED AWAY ON LABOR DAY
Beware of Currents at Great Lakes Beaches


MADISON, Wis. (8/31/99) -  Several recent drownings at Lake Michigan beaches
highlight the importance of understanding currents and how to escape from
them, according to Jim Lubner, Water Safety Specialist at the University of
Wisconsin Sea Grant Institute.

The two most important currents to know about are longshore and rip
currents, Lubner said.   Longshore currents flow along the shoreline, and
rip currents flow roughly perpendicular to the shoreline on the surface of
the water.

"You always want to swim perpendicular to the currents," Lubner said.  "In
the case of longshore currents, that's perfectly natural.  The current will
carry you along, parallel to the shore, and you should just swim toward
shore."

Rip currents are a little trickier, Lubner said.

"With rip currents, you get pulled out away from shore, and your natural
instinct may be to swim directly towards shore, against the current.  But
it's best to swim at right angles to the current, which in this case is
parallel to shore.  That way, you get out of the current the fastest.  Then
you can swim towards shore much easier," he said.

"These currents are usually pretty narrow, so you can get out of them in a
short distance," said Philip Keillor, a UW Sea Grant Coastal Engineering
Specialist.

"Currents are the result of powerful forces at work," Keillor said. "When
strong winds blow towards shore, they build up high waves and push water
towards the beach.  Between the shoreline and the breaking waves, the water
piles up higher than the lake level.  Gravity then pulls this elevated water
back into the lake, and this creates the currents."

A third kind of current is called an undertow, Keillor said.  "Swimmers at
the surface won't be affected much by the undertow, because they'll be above
it.  If you're near shore, it could knock you down, but you can just stand
up there."

Of course, the safest strategy is to avoid the currents altogether.  Knowing
when and where they usually form will help.

Longshore currents are most likely when the wind and waves come onshore at
an angle other than perpendicular to the shore, Keillor said.  The current
will then flow downwind along the shore.  For example, if you're standing on
shore facing the lake and the waves and wind are approaching from the right,
the longshore current will probably flow to the left.

Rip currents form when a longshore current turns away from the shore toward
the open lake.  They can also flow alongside large solid structures
extending off shore.  Swimmers, waders, wind surfers, divers, and fishers
should stay away from the water alongside harbor breakwaters and jetties,
long solid piers or groins, and large shoreline rock outcrops when the water
is rough.

Rip currents may also flow along underwater structures such as nearshore
reefs and troughs in the nearshore lakebed. 

One sign of rip currents is a stretch of breaking waves whose heights are
lower than the waves to either side.  Other signs of rip currents are
patches or lines of foam and debris, and discolored water moving away from
shore.  

 "Remember that the dangers of currents multiply when the water is cold,"
Lubner said.  "Cold water drains heat from the body very fast and interferes
with muscle operation and coordination.  You can't swim as far or as fast in
cold water."

Created in 1966, Sea Grant is a national network of 29 university-based
programs of research, outreach, and education dedicated to the protection
and sustainable use of the United States' coastal, ocean, and Great Lakes
resources.  The National Sea Grant Network is a partnership of participating
coastal states, private industry, and the National Sea Grant College
Program, National Oceanic & Atmospheric Administration, U.S. Department of
Commerce.

http://www.seagrant.wisc.edu





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