North Sound pollution

In April, a series of photos
circulated via email by environmental activist Kerry Horek caused a stir in
Grand Cayman. They pictured some mysterious green blobs floating in the waters
of the North Sound.

But rather than being raw sewage
from Water Authority sewage treatment plant, the blobs were revealed to be
algae blooms. The incident gave the Water Authority and the Department of Environment
a chance, via a joint press release, to discuss some of the major problems
affecting water quality in the North Sound.

They revealed that data collected
from their joint North Sound water quality monitoring programme which kicked
off in 2003 based on water samples taken from 13 North Sound locations.  The data are being used to build a long-term
database that will allow researchers to track trends and signs of pollution.

The data available in April showed
that the quality of the North Sound in areas away from the shoreline was
excellent. However, water quality in areas closer to land, especially in the
western part of the Sound and around  the
mouths of canals, showed signs of pollution as indicated by elevated levels of
bacteria, nutrients and chlorophyll-a.

These three pollution indicators
tell scientists a lot.

Bacteria in the water is a sign
wastewater, otherwise known as sewage, is present. While the Seven Mile Beach
corridor is hooked up to the sewage system, much of West Bay, George Town and
Bodden Town depend on septic systems to handle wastewater. Many of these aging
systems may be leaking their contents into the ground. DoE Deputy Director Tim
Austin has commented that due to Cayman’s water table, whatever goes into the
ground eventually makes its way into the marine environment.

Nutrients like phosphates and
nitrates signal pollution from fertilizers used in landscaping. And when
scientists talk about measuring chlorophyll-a in the water, they are measuring
the green pigment that is found in algae.

Nutrients and algae are connected,
as high nutrient levels in the water foster algae growth. While algae may seem
like a good thing to have in the water, too much of it causes major problems
for marine ecosystems. It blocks sunlight from travelling to the plants and
marine creatures that live on the seabed, and when algae dies and sinks to the
bottom, its decaying process starves the water of oxygen, disrupting the
ecosystem.

Development has its drawbacks

The Water Authority and the DoE say
that rather than placing the blame on a single source, the North Sound’s water
quality problems relate to the way Grand Cayman has grown and developed over
the past 50 years.

They note pollution leaching from
the George Town landfill, the way the Island handles its sewage, poorly planned
canal developments, fertiliser-enriched run-off from golf courses and other
landscaping, and the effects of recreational use all contribute to the North
Sound’s pollution.

In their joint statement, the DoE
and Water Authority also pointed to large-scale removal of mangrove wetlands
and seagrass on the western side of the North Sound to accommodate development.
Removing these natural filters, they said, has hurt the natural ability of the
local environment to lessen the impact of pollutants. 

 

A battle that can still be won

However, the study data also
revealed that things aren’t that bad – yet. Study data found that even in the
worst affected areas, the levels of bacteria seldom exceed the international
standards for bathing water.

Scott Slaybaugh, the Department of
Environment’s deputy director for operations and enforcement says the DoE now
has pages and pages of additional raw data from those monitoring sites.
However, to identify any more recent trends it needs to be analysed and transformed
into report documents, which will still take several weeks.

With no conservation law in place,
and to date no change in the status of the George Town landfill, the North
Sound is in no better shape than it was in April.

However, one change may be around
the corner, as the Cayman Islands Government has decided to sell the Water
Authority’s public sewage system. The double objective is to generate
government revenues, and to kick-start much-needed improvements to Cayman’s
sewage management systems.

The undertaking will include
expanding and improving the wastewater collection system and construction of a
new biological wastewater treatment plant.

As for the other pieces of the
puzzle?

Slaybaugh says the April statement
continues to be relevant.

“Modification to the natural
systems that protect the health of North Sound such as the removal of coastal
mangrove, removal of seagrass for channels, excessively deep canals, and
sedimentation from excavating channels will all contribute to the further
decline of water quality.”

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