Paper Title
Preliminary Water Quality Evaluation of The Vaisigano River, Samoa

This study analysed water samples collected from Vaisigano River on Upolu Island, Samoa to evaluate the degree of pollution by nutrients, heavy metals and microorganisms. Samples were collected monthly from December 2016 to April 2017 at 3 sites along the river and analysed for dissolved oxygen (DO), biochemical oxygen demand (BOD),total phosphorous (TP), nitrate (NO3 -), faecal coliform (FC), Enteroccoci (Ent) and the two heavy metals Cu and Pb. The results were used to calculate a water quality index (WQI) for each station with (WQIw) and without bacteria (WQIwt) to estimate the contribution of microbes to water contamination and to determine the overall health of each site. The WQIw values for the three stations ranged from (37.48 – 41.05)± 1.91 while WQIwt ranged from (41.14– 59.03)± 9.14. All values were below 100 which is the critical value for surface water safety for use for human activities, aquatic life and wildlife survival. Based on the WQI values, water quality at the three sites was generally poor. Keywords - Water quality index, pollution, microbial contamination, nutrients, Samoa