Water Pollution in Selected Coastal Areas in Western Province, Sri Lanka: A Baseline Survey

Abstract

The coastal area of the Western Province is faced with an acute environmental problem due to undesirable pollution of its waters from various wastes. The overall objective of this research was to determine the present status of water quality along the coastal line in the Western Province. In addition, an attempt was made to suggest recommendations to mitigate the pollution levels. The study was carried out from November 2011 to April 2012 and sampling was done on a monthly basis from Bentota to Negombo in selected coastal area. Dissolved oxygen (DO), water temperature, pH, turbidity, conductivity, total dissolved solids (TDS) and salinity were determined in situ and water samples were subjected to laboratory analysis using standard methods. Coastal water quality results revealed that, the average ammonia concentration (0.22 ± 0.16) mg/L and water temperature (30.0 ± 3.8) 0 C were below the maximum permissible limits of the proposed ambient water quality standards for Sri Lankan coastal waters. Average pH (7.91 ± 0.34) was within the ideal pH range for above standards whereas the mean concentration of DO was below the saturation level. An average value determined for Biochemical Oxygen Demand (12.08 ± 4.47) mg/l was much higher than the permissible threshold limit (>5 mg/l) which indicates the gross organic and inorganic pollution in all selected sampling locations in western coast. Proposed ambient coastal water quality standards should be modified using coastal water quality monitoring data and expert views and comments. Further studies needed to determine heavy metal concentration and bacteriological parameters to obtain clear picture of the pollution status.

Challenges in Biodiversity Conservation in a Highly Modified Tropical River Basin in Sri Lanka

“…Consequently, mid reaches are likely to experience the greatest eroded sedimentation flux. Moreover, nearly 8280 mt of nitrogen and phosphate fertilizers are applied annually to tea and rubber plantations and rice fields of the basin [35,60]. Ammonia concentration in coastal reaches averages around 0.22 mg L −1 , which is closer to maximum permissible (0.2 mg L −1 ) levels [60].…”

“…Although the focal environmental regulator of Sri Lanka, the Central Environmental Authority, identified these pollution sources decades ago, neither legal nor remedial actions have been taken thus far [31]. The contents of these industrial discharges include thermal effluvia, oils, petroleum impurities, heavy metals, and synthetic organic compounds such as polychlorinated biphenyls [27,[60][61][62]. Some of these contaminants are carcinogens (4-methylimidazole) or endocrine disrupters (Butyltin) [60,63].…”

“…The contents of these industrial discharges include thermal effluvia, oils, petroleum impurities, heavy metals, and synthetic organic compounds such as polychlorinated biphenyls [27,[60][61][62]. Some of these contaminants are carcinogens (4-methylimidazole) or endocrine disrupters (Butyltin) [60,63]. Chlorinated organic compounds have bioaccumulated in the tissues of fish and invertebrate inhabiting the lower reaches of the Kelani; these can induce chronic immunodeficiency and histological malformations [63].…”

“…Moreover, nearly 8280 mt of nitrogen and phosphate fertilizers are applied annually to tea and rubber plantations and rice fields of the basin [35,60]. Ammonia concentration in coastal reaches averages around 0.22 mg L −1 , which is closer to maximum permissible (0.2 mg L −1 ) levels [60]. Elevated phosphate and nitrate concentrations in the river from agricultural runoff have led to eutrophication and algal blooms in sluggish parts of the river, particularly during low-flow seasons [27,35,61].…”

Distribusi Spasial dan Faktor Kontaminasi Logam Berat di Pesisir Kota Makassar

“…Pembangunan yang massif di wilayah pesisir semakin mengeskalasi tekanan lingkungan yang berasal jauh dari pesisir (Yan et al, 2018). Pesisir merupakan daerah dengan topografi landai sehingga menjadi muara dari berbagai material yang berpotensi menjadi bahan pencemar (Hettige et al, 2014;Noor, 2019).…”