Water can be contaminated due to natural phenomena

by Dulmin Samarasinghe

There is a rich diversity of ecosystems in Sri Lanka, which includes wetlands, natural forests, marine and coastal ecosystems. Sri Lanka is considered as one of the world's twenty five 'Biodiversity Hotspots'. Overall, there are three Biosphere reserves, one World Heritage site, and 41 wetland sites included in the Asian Wetland Directory. Coastal ecosystems are diverse, but their fragmentation, is extremely high, these sources said.

Sixteen of Sri Lanka's coastal lagoons are classified as threatened and constitute nearly half of the country's threatened wetlands. Environmental degradation of the coastal zone is a major hazard faced by Sri Lanka. During the recent past, following the end of war, there has been increasing pressure for development in the coastal zone, particularly for tourism and recreational purposes, near shore fisheries, fish farming, industrial development and housing. Communities have exploited the use of natural resources, such as water, sand and coral, on a commercial basis.

Development has led to the reclamation of estuarial, lagoon and marshy lands. The disposal of sewage, has led to major, especially water pollution problems. The main threat to natural ecosystems is population growth and migration which reduces the space for ecosystems, including safe drinking water.

Water is essential for life. The purity and accessibility of drinking water are major concerns in the world. The amount of fresh water is limited and its quality is under constant threat due to human activities and natural environmental factors, according to the International Water Management Irrigation Institute (IWMMI). Preserving the quality of fresh water is important for drinking and food production. Health risks arise from the consumption of water contaminated with germs, toxic chemicals, and radiological hazards.

Access to safe drinking water improves the health of the people. Water is a vital natural resource for the public. Understanding where it is and how it moves under the ground is necessary to protect this resource. Experts predict wars in future for water, more than for oil. Water can be made available but providing clean water is a major task, according to sources of the IWMII.

It is of no use if clean drinking water cannot be afforded by a majority and if it cannot be used for agriculture due to contamination, then it is a sad state of affairs. Sri Lanka is blessed with natural water resources which could become a problem as multinational companies are keeping a close watch on these resources, expecting a water scarcity in the future, these sources said..

Soil from Gampaha to Matara which is iron rich is the cause of acidity in the water, said the Vice Chancellor of the Peradeniya University and Professor of Geology, Athula Senarathne. When such soil is close to a wetland, the pH value could decrease to 3 which is a low value, he said. There is no ideal pH value as it depends on pollutant factors in the environment. He said that acidity was not an indicator of pollution.

Referring to the recent water pollution in Thunnane, Hanwella, he said that the reduction of acidity in the water here was a natural phenomenon and the contention that the water is polluted is not exactly true. The soil in this area is mixed with Laterite (Kabook) which has natural iron. Laterite retains the wetness of soil. These conditions have contributed to the low acidity in the area. Professor Senarathne said that Laterite absorbs metallic contaminants. He said that iron gives a good taste to the water although too much of iron in the water is not good for health. Scientific proof is very important in case of contaminations and people should not come to conclusions without such evidence and create chaos in the country, Professor Senarathne said.

Industries and businesses are needed to develop the country. If there are allegations of environmental pollution due to industrial activity, those should be investigated using scientific methods. He said that people should not be frightened and instigated to commit violence as industries are crucial for economic development of the country. The Geology Department of the Peredeniya University has researched into natural phenomena and environmental issues over the years and in a position to help the country.

Sri Lankans have used groundwater resources extensively since ancient times for domestic purposes using shallow open wells in almost all parts of the country. Sri Lanka's largest ground water body extends over 200 km in the northwestern and northern coastal areas. The quality of groundwater is generally good and constant throughout the year. In northern and northwestern coastal areas excessive concentrations of iron and nitrates have been reported due to agrochemicals and fertilizers. Furthermore, due to uncontrolled abstraction of groundwater for domestic and agricultural uses, salt water intrusion has occurred in the coastal areas.

Water bodies which are mainly man- made, cover about four percent of the land. The land of the island is mostly made up of coastal plains, with mountains only in the south central part. Sri Lanka has more than 100 water basins. The climate of Sri Lanka is tropical and heavily influenced by monsoons that bring rain throughout the year.

The rainfall range is from under 1,000 mm to over 5,000 mm. Sri Lanka's groundwater resources are considered minor compared to its surface water resources.

The groundwater in Sri Lanka is used for domestic purposes, small scale irrigation, and for industries. However, in recent years, due to increased irrigation and population growth, both shallow and deep water deposits have been subjected to over extraction.