COASTAL AND ESTUARY RESERVOIR: CASE STUDIES FOR JOHOR RIVER BASIN

Abstract

This paper presents an alternative water storage concept at lower sea-river interface vis-à-vis the conventional dam/reservoir storage scheme in the upper headwater region of a river basin. Two (2) estuary or coastal reservoir schemes are proposed to meet the future water demand of Johor Bahru and its vicinity. The low flow yields of a 98% reliability (or design 1:50-year return period) for both river schemes are also presented. A hydrological assessment is carried out to correlate the hydrometric variables, i.e. rainfall and streamflow. A long term 54-year streamflow record is adopted as input to the yield calculation. The reliable yields of 98% reliability criteria are in turn estimated based on a water balance or mass conservation. This new paradigmatic shift of reservoir storage location from headwater region to lower estuary/coastal interface can harness sufficient yield to meet the future demand of Johor Bahru and vicinity.