Water polutions on Lake Illawarra. II. Thermal behaviour

Abstract

Temperature variations in surface and bottom water at 10 monitoring stations in Lake Illawarra were determined over the period 28 January 1972 to 31 May 1974. Except for the bay near Tallawarra Power Station, no permanent vertical temperature gradients were found. A statistically significant correlation was found between water temperature and distance from the power station, but no such relationship could be established for tidal heat flow either alone or acting together with the thermal discharge from the power station.

Mean water temperature for Lake Illawarra fluctuated in the range 11.6-25.6º C, compared with 15.7-24.0ºC for the sea adjacent to Wollongong Harbour. Seasonal maxima and minima in lake water temperature occur 3 weeks earlier than those of the sea.