Discolored water is an area of seawater having a color distinctly different from the surrounding water

Original warning text

1. DISCOLORED WATER IS AN AREA OF SEAWATER HAVING A
   COLOR DISTINCTLY DIFFERENT FROM THE SURROUNDING
   WATER. THESE OBSERVATIONS WILL NORMALLY BE OF
   SEAWATER HAVING A COLOR OTHER THAN THE BLUES AND
   GREENS TYPICALLY SEEN. VARIATIONS OF THE COLORS,
   INCLUDING RED, YELLOW, GREEN AND BROWN, AS WELL
   AS BLACK AND WHITE HAVE BEEN REPORTED. THIS MAY
   BE DUE TO DUMPING (POLLUTION), THE EXISTENCE OF
   SHOALS, OR UNDERWATER FEATURES SUCH AS SUBMERGED
   VOLCANOES. IN NEAR-SHORE AREAS, DISCOLORATION
   OFTEN RESULTS FROM DISTURBANCE OF SEDIMENT, E.G.,
   DISTURBANCES BY PROPELLER WASH. DISCOLORATIONS
   MAY APPEAR IN PATCHES, STREAKS, OR LARGE AREAS
   AND MAY BE CAUSED BY CONCENTRATIONS OF INORGANIC
   OR ORGANIC PARTICLES OR PLANKTON.
2. IN NORMALLY DEEP WATERS, DISCOLORED WATER CAN BE
   A STRONG INDICATION OF UNDERSEA GROWTH OF CORAL
   REEFS, SUBMERGED VOLCANOES, SEAMOUNTS, PINNACLES
   AND THE LIKE. AS THESE FEATURES GROW IN SIZE AND
   DIMENSION, THEIR ONLY INDICATION MAY BE IN THE
   FORM OF DISCOLORED WATER ON THE SURFACE OF THE
   SEA. MARINERS MUST BE PRUDENT IN SUCH WATERS,
   AS THEY WILL NORMALLY BE IN AREAS THAT ARE NOT
   WELL SURVEYED AND OUTSIDE OF ESTABLISHED ROUTES
   FOR OCEANGOING VESSELS.
3. NGA DOES NOT MAINTAIN A DATABASE OF SUCH OCCURRENCES
   WORLDWIDE. IN AREAS OF ACTIVE SUBMERGED VOLCANOES,
   DISCOLORED WATER IS A COMMON OCCURRENCE AND ALL
   SUCH REPORTS ARE CHARTED OR INCLUDED IN A NOTICE
   TO MARINERS CORRECTION. MARINERS ARE URGED TO
   SUBMIT NEW REPORTS OF DISCOLORED WATER TO THE
   NEAREST NAVAREA COORDINATOR VIA COAST RADIO STATIONS
   (FOR NAVAREA IV AND NAVAREA XII, BY E-MAIL TO
   [email protected]). REPORTS CAN ALSO BE SUBMITTED
   VIA THE NGA MARITIME SAFETY INFORMATION WEB SITE
   HTTP:POLLUX.NSS.NGA.MIL/SUGG/SUGG_FORM.HTML).