How good is the water quality of Lake Brunner?
Water quality monitoring in Lake Brunner began in the early 1990s. Trends in some water quality attributes, when evaluating the whole data record, have suggested a decline in Lake Brunner water quality. Nitrogen continues to increase, but contemporary trends in other water quality attributes are more positive. Despite these changes over time, water quality in the lake continues to be relatively pristine.
Seasonal mixing processes in large lakes are extremely important for the ecology of the lake, and are driven mainly by patterns in solar exposure, wind and river inflows. Phosphorus is the nutrient that is most likely to limit algal growth in Lake Brunner based on Total Nitorgen:Total Phosphorus ratios >20:1. Seasonal patterns are apparent for some parameters, particularly clarity and nitrate. Clarity was poorest during summer and highest in late winter/early spring. Nitrate concentrations were lowest in summer increasing to a peak at the end of winter, then decreasing as the weather warmed.
The water quality in Cashmare Bay is poorer than that found in the main lake due to Cashmere Bay’s inherently different suite of physical characteristics. This might be due in part to some nutrient recycling from sediment during periods when oxygen is absent. However, the quality reduction in Cashmere Bay’s deeper waters has not affected its surface waters, where nutrient and clarity levels have actually improved. Neither does it affect the rest of the lake.
Lake Brunner Surface Water Quality Updates: