Oficina Regional de la FAO para América Latina y el Caribe |

Exact quantities of water withdrawal are unknown since irrigation applications are rarely ever calculated, as total metering is only now being implemented for all abstractions and connections to the potable supply. Annual water withdrawal in the agriculture sector in 1996 was estimated at 19.01 million m3 (not including golf course irrigation at 0.9 million m3) whereas the domestic, municipal and industrial sector accounted for 25.85 million m3. Unaccounted water was about 35 million m3.
Almost all of the island's potable water is pumped from 21 groundwater wells in the karstic coraline area of the island, and small quantities obtained from two springs in the Scotland District. Water is treated with chlorine to meet WHO and US EPA guidelines and standards, prior to distribution. In the east of the island, there are a few relatively small rivers fed by spring sources, and ephemeral streams that flow during rain events. During the dry season (January to June) there can be water shortages in the potable supply to some areas. The use of water for other non-essential purposes is then prohibited island-wide. There is a sewerage system in place servicing the Bridgetown area.
Irrigation and drainage development
Irrigation potential was estimated in 1998 at 3 587 ha. In estimating this figure, consideration was given to land capability and maintaining safe yields from the groundwater supplies. The 1989 agricultural census indicated an irrigated area of about 1 000 ha. The island's potable water supply is used extensively by small farmers as their irrigation water supply. There are about 120 private hand-dug wells which are mainly used for irrigation. In the past many of the shallower wells were equipped with windmills but today the electric submersible pump is the norm. There is some relatively limited use of dams, springs, streams, roof catchments and road-catchments.
There is extensive use of conventional sprinkler systems and drip micro-irrigation systems for vegetable, fruit and horticultural crops. Drip irrigation has been widely used especially in the past ten years both by farmers and for landscaping. There is no surface irrigation (basin, furrow, flood recession) in the conventional sense, but the term is used to include the use of garden-hose flooding and hand-watering. The Government offers rebate incentives for the use of sprinkler and drip irrigation systems.
There are two Government-financed and operated irrigation schemes providing a piped, on-demand, pressurized water supply. In the north of the island, there is the Spring Hall Land Lease Project (land settlement project) with 22 farmer/family leased plots of land averaging about 10 ha each. The second scheme is the Rural Development Programme in the south, made up of nine individual irrigation systems servicing over 250 farmer-owned plots averaging under one hectare each. The systems are now quite dependable and small farmers rely upon them heavily during the dry season. Water charges are respectively US$ 16 cents and 22 cents per cubic metre of water used (compared to US $1.06 commercial rate for the potable supply). Regularly produced crops include tomatoes, cucumbers, hot peppers, sweet peppers, onion, carrot and beet. Other irrigated crops include citrus, bananas, plantains and cut-flowers. Irrigated vegetable farmers can get three crops in a season.
There is relatively little wastewater reuse at present for irrigation. A few hotels treat their wastewater and re-use it for irrigating lawns and gardens. Also a number of private homes run part of their wastewater to fruit trees or small banana patches in the backyard.
There is little drainage work carried out by private farmers. In some areas, beds are raised in the wet season to facilitate better drainage in the root zone. Generally, none of the drainage work is traditionally linked to surface irrigation or a high watertable. The Soil Conservation Unit of the Ministry of Agriculture has carried out substantial land stabilization works in the Scotland District. The drainage of surface and subsurface flows is essential for this land stabilisation. The flows are channeled safely via gabion structures to storage reservoirs or to stream courses which flow into the sea. Little of this water is now used for irrigation, and little quantification is made of the stream flow and irrigation potential in the area. Plans are being put in place to utilize some of this water for irrigation .