Grenada’s humid tropical climate shows a distinct dry season and wet season and the intensity and distribution of rainfall each year can directly influence how much freshwater is available from various sources.
Facts and Figures
75% of Grenada’s total rainfall each year occurs during the rainy season.
98% of Grenada’s population has access to piped water supply.
91% of households in Carriacou and Petite Martinique own cisterns as their main water storage.
The average person in Grenada currently consumes 34 gallons of water each day.
During dry season, daily water demand exceeds daily yield by ~5000 gallons.
The water sector’s vulnerability to climate change is assessed as medium-high.
Grenada receives on average about 1,150 mm of rain per year while in the neighbouring islands Carriacou and Petite Martinique experience a drier climate. Mainland Grenada primarily relies on 29 water supply facilities (23 surface water, 6 groundwater) delivered solely in potable form by the National Water and Sewerage Authority (NAWASA). Drinking water comes mainly from water harvested in dams in the mountain ranges of the northern region and is distributed to households through gravity systems. Groundwater contribution to domestic water supply is small and is used mainly during the dry season. Grenada’s current risk of water shortages is visible by the gap between demand and yield during the dry season (22,800 cubic metres per day or 5,015 gallons per day).
Current Daily Water Yield and Demand from NAWASA’s Water Supply Sources
|Rainy Season||Dry Season|
|Water Yield (cubic meters per day)||54,600||31,800|
|Water Demand (cubic meters per day)||45,500||54,600|
All public drinking water supplies are treated to meet WHO standards and there is a protocol for monitoring water quality. Read more
With limited groundwater and no permanent stream flows, the sister isles of Carriacou and Petite Martinique depend almost exclusively on rainwater harvesting for residential (namely through underground and above ground concrete cisterns) and agricultural uses. Desalination is also currently utilized by two major private sector entities to supplement the harvested rainwater domestic supply.
Water for agriculture comes predominantly from rainfall as well. For larger operations it is classically pumped downstream of rivers, while for small backyard-type gardening and livestock production, water comes from the public supply.
Water for nature includes lakes (Grand Etang, Lake Antione and Levera Pond) and waterfalls (Concord, Seven Sisters, Annandale, Tufton Hall and Mt. Carmel) along with their adjoining rivers and streams. These inland water sources in nature offer habitats for a variety of indigenous fauna. They also provide cultural services inclusive of recreation (sightseeing, swimming, fishing and river tubing). Some estuaries have developed into unique wetland systems providing not only recreational but educational services.
Grenada’s high exposure and high sensitivity to hurricanes, droughts and heavy rainfall, yet lower exposure to sea-level rise, is projected to be exacerbated because of climate change in the coming decades. Therefore, the GCREWS Vulnerability Assessment evaluated Grenada’s water sector as medium with a trend towards high.