Water profile of Guyana
Geography and Population
Guyana is located in the northern part of South America, with a 430 kilometer (km) Atlantic coastline and bounded by Venezuela in the northwest, Brazil in the west and south, and Suriname in the east. Guyana with 214,970 square kilometers (km2), is a sparsely populated country endowed with ample natural resources for agriculture. It is also one of the few countries in the world where population pressure on natural resources is virtually non-existent: 16.5 million hectares (ha) of the country's territory are made up of mostly inaccessible forests and woodlands, about 1.2 million ha are under permanent pasture and only 0.496 million ha are cultivated land. However, despite the abundance of its resources, Guyana is one of the poorest countries on the American continent, with an annual per caput income in 1996 of US$800. For administrative purposes, the country is divided into ten Regions.
The land comprises three main geographical zones:
- The coastal plain which occupies about 5% of the country's area and concentrates 90% of the population. The plain ranges 5 to 6 km wide along the coast.
- The white sand belt that lies south of the coastal zone. This area is 150 to 250 km wide and consists of low sandy hills interspersed with rocky outcroppings with hardwood forest and most of Guyana's mineral deposits. These sands cannot support crops and, if the trees are removed, erosion is rapid and severe.
- The interior highlands, the largest and southernmost of the three geographical zones, consisting of plateaus, flat-topped mountains, and savannas that extend from the white sand belt to the country's southern borders.
Guyana's population rose steadily from 375,000 in 1946 to 700,000 in 1970. Yet, in recent years, the population growth rate is negative (e.g. -0.78% in 1997) and, in addition, the net migration rate is also negative (-16.5 migrants/1000 population in 1997). The difference in birthrates between IndoGuyanese and Afro-Guyanese women, which as present from the 1950s to the 1980s, disappeared in the 1990s.
Guyana's economy is mainly based on exporting bauxite, sugar, rice, and, more recently, gold and forestry products. In 1996, Gross Domestic Product (GDP) was estimated at US$717.1 million. Agriculture ranks as the predominant sector in the economy and accounted for approximately 36% of the GDP in 1996. The sector employed 19% of the labor force in 1997. Agricultural activity is concentrated along the coastal belt where most of the population resides. During the last five years the privatization of the rice industry has resulted in the tripling of production. The privately managed sugar industry has become more efficient, increasing exports from 50,000 tons of sugar in 1985 to 3.5 million tons in 1995. Sugar production continues to be the most important industry in the agriculture sector (20% of GDP in 1995) and employing some 30,000 persons.
Climate and Water Resources
Guyana has a tropical climate with almost uniformly high temperatures and humidity, and much rainfall, modified slightly by trade winds along the coast. Temperatures in Georgetown are quite constant, ranging from 24°C to 32°C. Humidity averages 70% year-round. The interior, away from the moderating influence of the ocean, experiences slightly wider variations in daily temperature. Humidity in the interior is also slightly lower, averaging around 60%. Guyana lies south of the path of Caribbean hurricanes and none are known to have hit the country.
Rainfall is heaviest in the northwest and lightest in the southeast and interior. Annual averages on the coast near the Venezuelan border are near 2,500 millimeters (mm) and 1,500 mm in southern Guyana's Rupununi Savanna. Although rain falls throughout the year, about 50% of it is concentrated in the rainy season that extends from May to the end of July along the coast and from April through September farther inland. Coastal areas have a second rainy season from November through January. Rain generally falls in heavy afternoon showers or thunderstorms.
Guyana is an Amerindian word reputed to mean "Land of the Water". Numerous rivers flow into the Atlantic Ocean, generally in a northward direction. The Essequibo, the country's major river, runs from the Brazilian border in the south to a wide delta west of Georgetown. The rivers of eastern Guyana cut across the coastal zone, making east-west travel difficult, but they also provide limited water access to the interior. Waterfalls generally limit water transport to the lower reaches of each river. Estimates of surface water resources are not available over all of Guyana: there are data available from the main drainage basins (see Table).
|Characteristics of the main river basins in Guyana.|
|Drainage basin||Station||Surface area (km2)||Discharge (km3/y)||Specific discharge (m3/s/km2)|
The groundwater system comprises three aquifers. The "upper" sand is the shallowest of the three aquifers and its depth varies from 30 to 60 m, with thickness ranging from 15 to 120 m. It is not used as a source of water because of its high iron content (>5 milligram per liter (mg/l)) and salinity (up to 1,200 mg/l). Most potable water is obtained from the two deep aquifers. The "A" sand is typically encountered between 200 and 300 m below the surface with thickness ranging from 15 to 60 m. Water from the "A" aquifer requires treatment for the removal of iron. The "B" sand is found at about 300 to 400 m with thickness of between 350 and 800 m. Water from this aquifer has very little iron, a high temperature and a trace of hydrogen sulphide which can be treated with aeration.
Lakes and Dams
A small amount of the copious supplies of surface water which run off is trapped by a long low earth embankment to form large shallow dams locally known as "conservancies". The conservancies are located in the "backland" or upper stream catchment areas and comprise water-retaining embankments and structures.
These reservoirs are located on the Essequibo Coast Tapakuma Conservancy (Region 2), Boerasirie (West Demerara, in Region 3), East Demerara (Region 4), and the MMA (Region 5). The Tapakuma conservancy has been designed to provide irrigation to about 12,000 ha, Boerasirie supports 36,000 ha, East Demerara 34,500 ha, and MMA 17,500 ha. Boerasirie, Demerara, and Abary conservancies are entirely covered by weeds. While in most years water supply is ensured throughout the year, if droughts occur during the secondary November-January wet season, these conservancies may have water shortages. Water shortages may also occur in the Tapakuma conservancy, which is partly supplied by pumping from the Pomeroon river.
The gross theoretical hydropower potential of Guyana is 7,607 gigawatt-hours/year (GWh/year), of which 7,000 GWh/year was estimated to be technically feasible. Despite the country's large potential, there is only one hydropower plant in operation for 500 MW at Moca Moca in Region 9.
No official information has been found on water withdrawal, but estimated values by the World Resources Institute are shown in Figure 1. Irrigation has a very large demand for water. The highest density of population, roughly 90%, is within the coastal area and thus all residents of the coastal area depend wholly on groundwater supply to meet their domestic needs. One exception is the Georgetown area, which utilizes about 30% of surface water from the East-Demerara conservancy. Nationwide, water supply facilities include about 178 groundwater wells and eight surface water sources.
While the access to potable water through house connections and public standpipes is quite widespread, the water, and sanitation sector suffers from grave deficiencies due to the low quality of these services. There are three major water treatment facilities to produce drinking water, in Georgetown, New Amsterdam, and Guymine.
Irrigation and Drainage Development
The vast majority of agricultural activities takes place in the coastal plains. For more than 8 km inland the land is below sea level at high tide. Therefore, drainage and water control are major problems, and agricultural development has always been tied to the defence against water intrusion from the sea and from rainwater runoff.
Drainage throughout most of Guyana is poor and river flow sluggish because the average gradient of the main rivers is only 0.20. Drainage by gravity is possible only when the tide is low, and this form of drainage is affected by the ever-changing levels of the foreshore outside the sea defences. On account of this it has been necessary in many areas to resort to the expensive method of drainage by pumps. Land requires extensive drainage networks before it is suitable for agricultural use. Drainage canals occupy nearly one-eighth of the area of the average sugar cane field. The total length of the irrigation canals in Guyana is 485 km of main canals and 1,100 km of the secondary canals. Similarly, the main drainage infrastructure is about 500 km in length while the length of the secondary drainage system is 1,500 km.
Irrigated areas are concentrated between the mouth of the Pomeroon river and the Corentyne river. They are located in five out of the country's ten administrative divisions. All areas with fully developed drainage and irrigation facilities are classified as Declared Drainage and Irrigation Areas (DDIA). In addition, the sugar estates also have irrigation and drainage infrastructure. Figure 2 shows the irrigated areas per region in Guyana.
The water supply for the DDIAs and sugar estates is derived from water conservancies in Region 2, 3, 4, and 5, and from the rivers through pumping in Region 6. Very few control structures exist along the main canals and distributor canals. Flows in the secondary canals are controlled by headgates, and farmers derive water from secondary canals normally by gravity. Minor drains are interspersed with secondary canals that drain directly to the sea through sluice gates (some are associated with pumping stations) or to a facade drain, which drains to the sea at regular intervals. Sluice gates are open twice a day at low tides. Irrigation canals within sugar estates have no slope and are often used for cane transportation.
All irrigation schemes in Guyana have the same delivery arrangements. An irrigation schedule gives the date and duration of the openings of head regulators on secondary canals. During the alloted period, the farmers can divert water on demand. There are no metered structures, and the entire system is operated through the concept of nearly constant water level. The volume released at any point throughout the systems is unknown.
Most irrigation infrastruture needs extensive rehabilitation, with the exception of some sugar estates and some infrastructure that is being maintained by large-scale farmers. The systems' state of disrepair contributes significantly to lowering Guyana's water use efficiency. Another important cause of poor water efficiency is inadequate water management, a result of conflicting needs of farmers who have different cropping calendars. While there are no recent studies measuring water use efficiency, efficiency levels are unlikely to exceed 25%.
Crop and livestock production (except for sugar cane) are characterized by the predominance of small farms. According to the last farm household survey, farms of less than 6 ha accounted for about 75% of the country's 24,000 farms. It is estimated that about 70%-80% of these small farms are geared to rice production. Many of these small farms combine their crop production with some milk production. There are, however, several larger agricultural operations that include private rice growers, some medium- and large-sized forest and fishing operations, and large public-sector enterprises.
In the 1980s, sugar and rice were the primary agricultural products, as they had been since the nineteenth century. Sugar was produced primarily for export whereas most rice was consumed domestically. Other crops included bananas, coconuts, coffee, cocoa, and citrus fruits. Small amounts of vegetables and tobacco were also produced. During the late 1980s, some farmers succeeded in diversifying into specialty products such as heart-of-palm and asparagus for export to Europe. The extent of Guyana's economic decline in the 1980s was clearly reflected in the performance of the sugar sector. Production levels were almost halved, from 324,000 tons in 1978 to 168,000 tons in 1988. Sugar production for 1994 was 252,615 tons and was the major export commodity, contributing 28% to total exports. The rice industry has been leading growth (1993-96) with production and export earnings rising steadily. In 1995, rice production reached 350,000 tons.
The present administrative organization of Guyana's water resources has been in place for over a century. There are some fifteen agencies administering the legislation relating to water and their functions often overlap either directly or indirectly. The functions of the more important of these agencies are as follows:
- (a) Drinking water supply and sanitation
The Guyana Water Authority (GUYWA), under the policy direction of the Ministry of Public Works, Communications and Regional Development, provides water supply services for the whole country with the exception of Georgetown, New Amsterdam, and Linden, where the systems are run by municipalities. Since 1984, responsibility for provision of water services belongs to the Regional Democratic Councils. The Ministry of Health monitors water quality and has the responsibility for sewerage and sanitation activities. The municipalities are responsible for the construction, operation, and maintenance of urban drainage systems.
- (b) Irrigation and drainage
Overall responsibility for drainage and irrigation in Guyana is vested in the National Drainage and Irrigation Board (NDIB). The NDIB is mandated to provide drainage and irrigation services in Declared Drainage and Irrigation Areas (DDIAs). All DDIAs are administered by the Regional Democratic Boards, except the Mahaica-Mahaicony-Abary system that is managed by an independent water authority. Regional Democratic Boards are responsible for maintenance of the conservancies, water allocation from the conservancies, operation of the reservoirs, and maintenance of the dams and head regulators. The Regional Democratic Boards do not themselves collect the water users' share of costs, this is the responsibility of the local authorities. Local authorities are required by the Drainage and Irrigation Act to assess the level of the drainage and irrigation rates on DDIAs and levy charges on landowners.
- (c) Other water uses
- The Ministry of Public Works, Communications and Regional Development has responsibility for establishing water sector policy.
- The Hydrometeorology Department of the Ministry of Agriculture has the responsibility for the monitoring and assessment of surface and groundwater resources and for providing basic meteorological information.
- The Guyana Electricity Corporation (GEC) is responsible for the generation, transmission, and distribution of electricity.
Trends in Water Resources Management
The challenges the Government faces in its task to support the development of agriculture are enormous. The sector's potential relies heavily on extensive rehabilitation of the country's deteriorated infrastructure and on technological improvements. This task will require not only extensive public sector efforts, but increased involvement and participation of the private sector in areas such as maintenance of drainage and irrigation systems.
The principal options Guyana plans to pursue for further development of the agricultural sector and achievement of improved water management are likely to include:
- (i) increase in productivity through better seeds and agricultural practices
- (ii) development and rehabilitation of the irrigation and sea defense infrastructure: evidence from pilot projects on the coast shows farmers are willing to pay rent or user fees to get better operation and maintenance services to the drainage and irrigation systems which serve them
- (iii) promotion of privatization through a program of complementarity between the Government and the private sector
- (iv) improved land tenure
- (v) crop diversification: new trends in the expansion of non-traditional crops are expected to enhance the food security and nutritional needs of the country
In terms of external trade, the 1990s have seen an improvement of competitiveness: non-traditional exports such as fruits and vegetables are being exported in increasing quantities to the neighboring countries. Close to 500,000 metric tons of rice are exported to nearby Caribbean countries annually and increased demand is expected for the medium term since the commodity is a staple of the diet. However, Guyana's food exports depend precariously on rice and depend heavily on the policies of the European Union in terms of rice imports.
- Water profile of Guyana, Food and Agriculture Organization.
- World Factbook: Guyana, Central Intelligence Agency.
- World Bank.1992. Guyana Agricultural Sector Review. Report number 10410-GUA. Washington D.C., 32 p.
- FAO-Investment Centre-Caribbean Development Bank.1997. Guyana: Poor Rural Communities Support Services Project: Drainage and Irrigation Component. Report number 97/064 CDB-GUY, three volumes. Roma.
- World Bank.1993. Guyana: Public Sector Review. Report number 11753-GUA, Caribbean Division, two volumes. Washingtonm D.C.
- Naraine, R. 1999. Water for Food: Guyana's Vision. National Drainage and Irrigation Board, Ministry of Agriculture, Government of Guyana. Presentation at America's Regional Roundtable Consultation on Water for Food, Montreal, Canada.
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