Some chemical and physical relationships on lake ontario

Submersible recording water chemistry and current instruments were concurrently operated on a submerged tower located approximately 2.5 km offshore on Lake Ontario. This area is influenced by several large sewage treatment plant discharges with the closest discharge 1.6 km away. The instruments were 3.0 m off the bottom in 9.6 m of water and operated primarily during the months of June and November, 1970. One-thousand fivehundred and seventy-four hourly measurements were made of currents, temperature, dissolved oxygen, conductivity, pH and turbidity. The measurements were validated with field measurements by other methods. Time series analyses of the collected data showed that time variations of water chemistry for 8–15 h cannot be explained by water movements for distances of 2 km from a major waste discharge. A measure of the biological activity as well as other chemical and physical processes is required to determine concentrations of the measured chemical parameters. Current magnitudes with a mean value of 3.5–6.0 cm s⁻¹ are not the primary mechanism responsible for the distribution of water chemistry in this location for the 8–15 h period. The need for the evolution of reliable recording chemistry instruments which can be used in the offshore regions of the lakes is clearly indicated to effect a better understanding of the near shore chemistry at distances of 2 km from known waste discharges. Long-term period (greater than 15 h) temporal variations of the measured water chemistry are related to water movement patterns.