| Report Year: 2009 |
| East Lake (Osceola), Clarke County |
| Summary Data Table |
| Parameter | 6/18/2009 | 7/22/2009 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 4.2 | 4.2 | 4.2 | 4.1 | 4.1 | 4.3 | 4.5 | 4.1 | 4.3 | 4.3 | 4.4 |
| Thermocline Depth (m) | 3.5 | 1.8 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Secchi Disk Depth (m) | 0.7 | 0.5 | 0.6 | 0.8 | 0.6 | 0.3 | 0.4 | 0.3 | 0.4 | 0.5 | 0.4 |
| Temperature(oC) | 21.7 | 24.0 | 22.9 | 26.5 | 24.0 | 24.7 | 22.8 | 23.5 | 25.1 | 23.1 | 24.7 |
| Dissolved Oxygen (mg/L) | 8.9 | 11.8 | 10.3 | 12.5 | 4.6 | 11.4 | 10.6 | 9.9 | 7.1 | 7.9 | 9.5 |
| Dissolved Oxygen Saturation (%) | 101 | 140 | 120.5 | 156.7 | 53.9 | 136.7 | 123.4 | 115.8 | 86.5 | 91.0 | 116.0 |
| Specific Conductivity (μS/cm) | 340.0 | 280.0 | 310.0 | 275.2 | 293.7 | 288.9 | 276.1 | 264.4 | 421.6 | 233.2 | 216.9 |
| Turbidity (NTU) | 21.5 | 45.5 | 33.5 | 22.2 | 60.6 | 25.4 | 33.5 | 33.8 | 29.9 | 43.9 | 26.0 |
| Chlorophyll a (μg/L) | 58.0 | 33.0 | 45.5 | 50.4 | 43.5 | 190.8 | 73.0 | 27.9 | 66.2 | 47.8 | 32.1 |
| Total Phosphorus as P (μg/L) | 285 | 503 | 394 | 488 | 267 | 272 | 313 | 281 | 224 | 378 | 376 |
| SRP as P (μg/L) | 139 | 284 | 211 | 341 | 95 | 80 | 147 | 96 | 36 | - | - |
| Total Nitrogen as N (mg/L) | 1.76 | 2.33 | 2.05 | 1.63 | 2.12 | 1.76 | 1.82 | 1.97 | 1.54 | 2.40 | 2.86 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 210 | 16 | 108 | 52 | 282 | 138 | 128 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 46.2 | 3.1 | 24.6 | 11.9 | 14.1 | 12.1 | 48.9 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | 0.15 | 0.12 | 0.13 | 0.16 | 0.12 | 0.21 | 0.19 | 0.29 | 0.14 | 0.35 | 0.17 |
| TN:TP ratio | 6 | 5 | 5 | 3 | 8 | 7 | 6 | 8 | 7 | 6 | 8 |
| pH | 8.8 | 9.3 | 9.1 | 9.2 | 8.0 | 8.4 | 9.1 | 9.3 | 8.3 | 8.0 | 7.2 |
| Alkalinity as CaCO3 (mg/L) | 151 | 135 | 143 | 132 | 105 | 108 | 110 | 74 | 105 | 99 | 125 |
| Silica as Si (mg/L) | - | - | - | - | - | 4.77 | 5.31 | 5.02 | 5.81 | - | - |
| Dissolved Organic Carbon (mg/L) | 7.10 | 7.89 | 7.50 | 8.81 | 11.54 | 8.66 | 10.38 | 15.31 | 16.41 | - | - |
| Inorganic Suspended Solids (mg/L) | 6 | 9 | 7 | 6 | 5 | 8 | 9 | 12 | 7 | 10 | 5 |
| Volatile Suspended Solids (mg/L) | 10 | 19 | 14 | 12 | 8 | 14 | 13 | 16 | 15 | 11 | 5 |
| Total Suspended Solids (mg/L) | 16 | 28 | 22 | 18 | 14 | 22 | 22 | 28 | 22 | 22 | 9 |
| Carlson Trophic State Index (Secchi)* | 65 | 70 | 67 | 64 | 68 | 76 | 72 | 75 | 73 | 72 | 74 |
| Carlson Trophic State Index (Chl a)* | 70 | 65 | 68 | 69 | 68 | 82 | 73 | 63 | 72 | 69 | 65 |
| Carlson Trophic State Index (TP)* | 86 | 94 | 90 | 93 | 85 | 85 | 87 | 85 | 82 | 90 | 90 |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |