1 minute read
Figure 18: Manning River TN and TP readings from 2015-18
from Draft Manning River Catchment and Estuary and Catchment Management Program 2021-2031 - Main document
Nutrients are elevated. Total nitrogen exceeded the ANZECC total nitrogen trigger of 350 ug/L approximately twice a year with three results for the period exceeding 800 ug/L. Total phosphorus levels exceeded the ANZECC trigger of 25 ug/L in a similar manner.
Nutrient levels are greatly influenced by erosion and sediment migration to the waterway, as suggested by the apparent correlation with higher river flows.
Total nitrogen and phosphorus results for the 2015-2018 period are represented in Figure 18.
Figure 18: Manning River TN and TP readings from 2015-18
For turbidity, only one event exceeded the ANZECC trigger over the sampling period. Turbidity is a measure of sediment inputs from erosion.
