Beware of turquoise-blue waters! They are great for seascapes photography
, but you will not find any live corals in there. Turquoise color is a reflection of the skies above water covered with white sands; sands that bleach and kill the corals. Many communities, to "protect" their eroded sandy beaches, bring in more sands to shore up their waterfront. These sands get swept away by high surf and currents covering and killing the corals; the cycles are repeated. As more sands are "withdrawn" from the beaches, water levels are lowered resulting in warmer temperature at shallow depth
; another factor in bleaching and killing the corals.
According to physics principles, shallow depths at beaches acquire fierce levels of waves due to abrupt stopping of incoming wave momentum; causing beach erosion. Adding more sands exacerbate the situation; ditto effect for erecting walls, as is New Orleans
and throughout the length of the Mississippi
The best snorkeling/diving sites are located in deep waters with cooler temperature (below 65F) and with a noticeable current
(1-2 knots, that brings plankton); deep navy
blue waters are best for diving