Mon | Feb 24, 2020

Overgrowth of algae behind discolouration of St Mary river - NEPA

Published:Monday | August 19, 2019 | 3:57 PM
Contributed photo.

The National Environment and Planning Agency (NEPA) is confirming that the “reddish-pink” discolouration of the Outram River, that runs through Port Maria in St Mary, is due to the overgrowth of algae resulting in the phenomenon known as Red Tide.  

Red tide is made up of numerous microscopic plant algae also known as phytoplankton.

NEPA says laboratory analysis of samples collected at the revealed a high concentration of phytoplankton, which is an indication of a high nutrient level in aquatic systems and hence the algal growth.

The agency says the overgrowth of algae is attributed to changes in environmental conditions, specifically a significant increase in the levels of nutrients in the water.

The build-up of algae is also attributed to the blockage at the mouth of the Outram River and the low flows of the river, as a result of the drought conditions being experienced.

Anthony McKenzie, Director, Environmental Management and Conservation recommends that “the blockage of the sand berm at the mouth of the river is to be gradually removed in order to ameliorate the situation.”

He emphasised, “channels should be created through the blockage to manage the flow, rather than the total removal of the material. This approach prevents issues including a fish kill, associated with the occurrence of an algal bloom in the coastal environment.”

NEPA says it has been in dialogue with the St Mary Municipal Corporation which has indicated that, over the coming days, the berm at the mouth of the river will be partially opened to allow for the controlled release of water from the area and the flushing of the river.

Noting that the water is not safe for consumption or household use, NEPA is urging the public to stay away from the river until the corrective actions have been taken.

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