When visiting a beach in the Dominican Republic you may wonder why the water is so incredibly clear and beautiful. Some describe the water as blue, azure, cerulean, or just blue/green. Regardless, most people would agree that it’s absolutely breathtaking. After years of wondering, I decided to find out for myself why the waters of the Dominican Republic are so beautifully clear and blue.

The Dominican Republic’s sea is so clear and blue because it has little presence of plankton – or other substances – and it’s relatively shallow so most of the light is reflected. As a result, we see beautiful clear blue water. Water gets its color from the interaction of sunlight with water and the substances in the water.

Wait, What?

The light that is absorbed is pulled in by the water and transformed into heat energy. Deeper waters absorb more.

  • Scattered light bounces off the surface into different directions than where it came from. Blue wavelengths of light are scattered at different angles resulting in varying shades of blue.
  • Reflected light bounces off the surface into a single direction from where it came from. Much of the ocean’s blue color is a reflection of the sky above. Red, orange, yellow and green wavelengths of light are primarily absorbed (vs. scattered or reflected) and blue wavelengths reflected, which is the main reason the ocean is primarily blue.

Substances In The Water Affect its Color

The substances beneath the water are primarily free-floating plankton but can be any number of other suspended particles. These substances increase the scattering of light so less light is reflected.

Plankton uses a green element called chlorophyll in order to produce carbon via photosynthesis. Since plankton prefers to absorb red and blue portions of the light spectrum it then reflects green light vs blue. In other words:

  • High amounts of plankton result in a greener appearance
  • Low amounts of plankton result in a bluer appearance.

The Absence of Plankton Gives us Beautiful Clear Blue Waters, But What About Sea Life?

I wanted to circle back to the topic of plankton since it’s such a major factor in why Dominican waters are so clear and blue.

Plankton is essential for sea life survival. According to the Oceanic Research Group, “Plankton is the base of the food web in all oceans”.

This would lead you to think that while you’re enjoying a beautiful Dominican beach due to the absence of plankton, sealife must be struggling to survive without it! Well, not really. Over many years sea creatures in this region have had to adapt and evolve in order to survive.

According to the Oceanic Research Group “The most successful solution to the problem [absence of plankton] is the coral reef community. The reef is a living structure made by coral animals. The reef itself is adapted to survive and grow in the tropical seas. As it grows, it provides a safe haven for fish and invertebrates to hide and make nests. This draws all kinds of life to the reef. The smaller fish draw larger fish and sharks. So the reef forms the basis of a complete ecosystem.” Which is good news for you snorkelers out there. Clear, blue, and teeming with beautiful life, Dominican beaches have it all.