Grafham Water is an artificial lake or reservoir at Perry near Huntingdon,
Cambridgeshire (Great Britain). The
club rules state "the name of the Club shall be the Grafham Water Sailing Club
and the burgee of the club shall be green over blue, divided by a wavy white
band."
The sailing club maintains a neat flag system to control use of the water by
members and visitors. (...) Flags are flown from the main jetty and occasionally
from other shore side flag poles as stated on this page: http://www.grafham.org/?page_id=32.
A direct link to clickable table, presenting the various signals (captions
edited, merged with comments from previous page):
http://www.davas.co.uk/gwsc/wp-content/uploads/flags2.JPG.
Yellow: restricted sailing area 1 only (restricted area
bounded by yellow buoys used routinely on weekdays to ensure you are within
sight of the duty coxswain).
Blue saltire on green: algae present wear suitable
protection and wash after sailing.
Broad blue diagonal stripes,
descending, on white: experienced windsurfers only water closed to
dinghies, catamarans and keelboats. This flag will be flown at the coxswain's
discretion in strong wind conditions to indicate that only experienced
windsurfers may launch. These are conditions not windy enough to justify
closing the lake but too windy for most craft other than windsurfers to cope.
Black: compulsory wearing of wet/dry suits (from 1st Nov to 31st March or
when water temperature is below 5 degrees C).
The above
signals are an interesting variation on the better known
beach signal flags. Jan Mertens, 20 May 2011