Abstract:
Saltwater intrusion is a natural process that occurs in virtually all coastal
water bodies. It causes various effects resulting high breeding of fish, prawns, water
hyacinths and drinking water problems due to contamination of fresh water with
saline water. Present study, focuses on the intrusion of saltwater along Bolgoda
estuary. Objectives of this research are to determine the evidence of saltwater intrusion
along the Bolgoda estuary and identify the social and ecological problems related
thereto, such as the effects on riparian plants and aquatic life and the adoption of
mitigatory measures. Investigation was carried out by measuring water quality
parameters (Conductivity, pH, Dissolved-Oxygen, Temperature and Oxidation-
Reduction Potential) along the estuary water in vertical profiles as well as water in
nearby monitoring wells. Observations were made on different tidal periods to study
the rate and extent of saltwater intrusion along the river. These vertical profiles of
water quality parameters were taken along the river approximately around 50m
intervals, starting from Panadura estuary towards the North direction of the estuary
up to about 12 km. Results shows salt water intrusion is a prominent feature during
the neap tide period than the spring tide period. Therefore, tidal variation does not
control salt water intrusion for our sampling periods. However, salt water intrusion is
lower in the periods with higher rainfall period. Therefore rainfall and possibly
evaporation is the main controlling factor of the salt water intrusion at Bolgoda
Estuary. Salt water intrusion in this estuary is an advantage to the surrounding
community since salt water removes water hyacinth, and promotes prone farming.
Citation:
Jayamali, K.V.S.D., Wijayawardhana, H.M.J.T., Rajakaruna, R.M.C.M., Indika, J.P.R., Rambukwella, U.D.P., & Ratnayake, N.P. (2008). Investigation of salt water intrusion along the Bolgoda estuary. In S. Karunaratne (Ed.), Proceedings of the 3rd Annual Conference on Mining for Sustainable Development – A Multidisciplinary Approach (pp. 25-28). Department of Earth Resources Engineering, University of Moratuwa.