Conn. Agencies Regs. § 22a-426-6 - Lake trophic categories
Parameters and Defining Ranges for Trophic State of Lakes in Connecticut |
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Trophic State Based on Water Column Data |
Parameters |
Defining Range |
Oligotrophic |
Total Phosphorus |
0-10 ug/l spring and summer |
Total Nitrogen |
0-200 ug/l spring and summer |
|
Chlorophyll-a |
0-2 ug/l mid-summer |
|
Secchi Disk Transparency |
6 + meters mid-summer |
|
Mesotrophic |
Total Phosphorus |
10-30 ug/l spring and summer |
Total Nitrogen |
200-600 ug/l spring and summer |
|
Chlorophyll-a |
2-15 ug/l mid-summer |
|
Secchi Disk Transparency |
2-6 meters mid-summer |
|
Eutrophic |
Total Phosphorus |
30-50 ug/l spring and summer |
Total Nitrogen |
600-1000 ug/l spring and summer |
|
Chlorophyll-a |
15-30- ug/l mid-summer |
|
Secchi Disk Transparency |
1-2 meters mid-summer |
|
Highly Eutrophic |
Total Phosphorus |
50 + ug/l spring and summer |
Total Nitrogen |
1000 + ug/l spring and summer |
|
Chlorophyll-a |
30 + ug/L mid-summer |
|
Secchi Disk Transparency |
0-1 meters mid-summer |
Notes
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