Ninety-five percent of the country’s total supply of potable water comes from ground water. The ground water resources of Suriname are used for public supply and to lesser extent industry. Suriname contains two hydrologically distinct provinces, the Interior Precambrian Shield of crystalline rocks, comprising 80 percent of the country, and the coastal plain basin, comprising the remaining 20 percent. There is an abundance of good quality groundwater which is contained in the coastal basin. Groundwater in the young coastal plain is not renewable, groundwater in the old coastal plain and savannah belt area are renewable.
The aquifers of Suriname are in the coastal basin, which are built up of unconsolidated sediments consisting of a sequence of clay, sands, sandy clay, clayey sands, gravel, with more or less kaolin content, and thin bed organic compound. These aquifers which have been classified based on the geological ages are the:
The most important freshwater aquifers from where water is withdrawn are the:
Ground water conditions in the northern Interior Precambrian Shield are generally unfavorable, because the geological formations in this province have little or no primary permeability. The south which is an active system is recharged directly from rainfall and coincides with the savanna and old coastal plain. Generally the salinity increases towards the coast. The water in the Zanderij aquifer is fresh throughout the old coastal plain, and brackish in the young coastal plain, particularly adjacent to the rivers. The change is abrupt. In the Coesewijne aquifers freshwater continues farthest north. Higher salinity extends farthest inland along concealed lines in the A-Sand.
The salinity of groundwater is commonly expressed in total dissolved solids (TDS) in mg/l and chloride concentrations in mg/l or mmol/l. The table below shows a common classification.
Salinity class |
TDS in mg/l |
Cloride in mg/l |
Fresh |
– |
<50 |
Fresh |
1-1,000 |
0-250 |
Moderate brackish |
1,000-12,000 |
250-7,000 |
Brackish |
12,000-24,000 |
7,000-14,000 |
Saline |
24,000-34,000 |
14,000-20,000 |
Hypersaline |
>34,000 |
>20,000 |
The Surinamese Water Supply Company (SWM) has currently 15 productions stations. The number of groundwater wells is about 78. Characteristics of these stations are shown in the tables below. The annual water production is about 38.106 m³ water.