Abstract:
Groundwater quality become an important issue due to increasing of anthropogenic activities.
Development of an area that followed by population growth impacting not only quantity but also
the quality of groundwater. Coastal area of northern Bengkalis Island also facing the water
problem. The excessive used of water resources causing the depletion of groundwater quality.
Seawater intrusion is a common hassle that can be found along the coastal area of Bengkalis
Island. Higher coastal erosion rate lead to shoreline retreat that affecting the subsurface
freshwater-seawater interface. Geological condition of study area that dominated by peat soil layer
also bring an impact to groundwater quality. Groundwater monitoring had been conduct to map
the water quality zone. Existing dug wells had been measured to obtain several in-situ parameters.
The field data then being assess to acquire the important information of recent groundwater
condition of the study area by comparing to water quality standards such as Indonesian Ministry of
Health Drinking Water Standard 2010 and WHO Drinking Water Standard 2017. Brackish water
had been detected in several wells and river section in the northern part of study area. The
brackish water shows higher TDS value compared to freshwater. In the southern part, the brownish
water had been found in the several wells that lied on the peat land. In general, groundwater
quality in study area has several problems that needs to be resolved. Advance study need to be
carried out to ensure the impact of recent groundwater quality and to find the appropriate
remediation program.
