Parameter | Action Threshold Level | Units | Description |
Total algae cell density | 100,000 | Cells・mL−1 | Algae dispersed in the water column, independent of classification |
Blue-green algae cell density | 10,000 | Cells・mL−1 | Cyanobacteria cells only, even if the above overall algae density is not met |
Green algae mat coverage | 5% | Surface or benthic area pond coverage | 18.6 sq m (~200 sq feet) visible area covered with green algae (or other non-blue green algae types) |
Blue-green algae mat coverage | 2.5% | Surface or benthic area pond coverage | 9.3 sq m (~100 sq feet) coverage with cyanobacteria as dominant biomass of mat |
Blue-green algae scum coverage | 2.5% | Surface area pond coverage | 9.3 sq m (~100 sq feet) coverage with cyanobacteria as dominant component of accumulated surface scum |
Chlorophyll α concentration | 20 | µg・L−1 | Measured in homogenized planktonic water sample |
Secchi Depth | 45.7 | cm | 3 point average |