| || || Taloiburi, Exsley Jemuel.|
| || || An evaluation of the effects of wastewater treatment initiative on water quality in coastal waters along the Coral Coast, southwest Viti Levu, Fiji Islands|
Author:Taloiburi, Exsley Jemuel.
Institution: University of the South Pacific.
Call No.: pac In Process
Copyright:10-20% of this thesis may be copied without the authors written permission
Abstract: Most tourist hotels and villages on the Coral Coast of Fiji are situated along the coastline resulting in higher observed coastal wastewater pollution. This study was aimed at evaluating the effects of wastewater treatment initiatives on water quality in coastal waters along the Coral Coast, Fiji. Monitoring was undertaken on a planted gravel bed constructed wetland at Tagaqe Village, Crusoe‘s Resort wastewater treatment system, Coral Coast nearshore sites, Votua Village Creek, and an ex-situ greywater treatment drum experiment. Results for the wetland showed removal efficiency range of 94.7-99.3% for faecal coliform, E/coli, total suspended solids (TSS) and biological oxygen demand (BOD). Nitrogen elimination ranged between 50% for nitrite and 82.6% for ammonia. Total Kjeldahl Nitrogen (TKN) declined by 75.5%, Total Phosphorus by 69.1% and phosphate by 75.5%. The system at Crusoe‘s Resort indicated removal range of 63.6-94.7% for faecal coliform, E/coli, TSS and BOD. Nitrite was reduced by 50.9%; nitrate by 68.5%; ammonia by 72.7%; and TKN by 50.1%. Total phosphorus was reduced by 60.5% and phosphate by 70.7%. For the Coral Coast nearshore water quality, results showed a mean salinity of 32ppt; temperature of 29.4ºC; dissolved oxygen level of 6.10mg/L; conductivity 49.92mS/cm; nitrate 4.16µM; ammonia 2.09µM; nitrite 0.35µM and 0.43µM for phosphate with a N:P ratio of 17. Votua Creek data showed that the lower housing, bridge and creek mouth experience polluted wastewater discharges relative to upper housing and the dam. The village and Mike‘s Diver tap water were observed to be of unsafe drinking water quality standards, without further treatment, but the housing tap water was safe. The greywater treatment drum experiment showed general removal efficiencies for all parameters in both mesocosms but varied considerably between different loading regimes, sampling intervals and individual water quality parameters.