| Report Year: 2011 |
| Bob White Lake, Wayne County |
| Summary Data Table |
| Parameter | 5/24/2011 | 7/12/2011 | 8/22/2011 | 2011 | 2010 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 3.5 | 2.9 | 2.5 | 3.0 | 3.0 | 3.1 | 3.0 | 3.0 | 3.3 | 3.5 | 3.5 | 3.6 | 3.8 | 3.6 |
| Thermocline Depth (m) | 1.0 | Nil | Nil | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Secchi Disk Depth (m) | 0.2 | 0.2 | 0.3 | 0.2 | 0.2 | 0.3 | 0.2 | 0.3 | 0.3 | 0.2 | 0.3 | 0.2 | 0.2 | 0.3 |
| Temperature(oC) | 21.8 | 26.8 | 27.4 | 25.3 | 24.5 | 25.1 | 27.0 | 25.7 | 26.6 | 23.4 | 26.4 | 26.3 | 24.1 | 23.8 |
| Dissolved Oxygen (mg/L) | 7.9 | 4.9 | 9.9 | 7.6 | 5.9 | 6.1 | 10.4 | 6.1 | 8.0 | 8.2 | 8.4 | 6.6 | 7.9 | 7.4 |
| Dissolved Oxygen Saturation (%) | 90 | 62 | 125 | 92.4 | 70.4 | 73.6 | 131.9 | 74.9 | 99.9 | 97.7 | 104.1 | 82.1 | 93.6 | 87.7 |
| Specific Conductivity (μS/cm) | 260.0 | 150.0 | 170.0 | 193.3 | 233.3 | 216.7 | 235.3 | 363.2 | 311.0 | 208.1 | 317.5 | 423.7 | 171.2 | 189.9 |
| Turbidity (NTU) | 39.3 | 127.0 | 52.9 | 73.1 | 49.9 | 45.7 | 83.4 | 94.9 | 238.7 | 207.5 | 46.6 | 97.5 | 154.0 | 44.2 |
| Chlorophyll a (μg/L) | 8.2 | <5 | 40.4 | 17.5 | 12.4 | 11.3 | 49.6 | 41.6 | 159.1 | 48.1 | 23.0 | 9.5 | 16.6 | 10.6 |
| Total Phosphorus as P (μg/L) | 171.5 | 218.8 | 174.1 | 188.1 | 214.2 | 204.7 | 248 | 183 | 196 | 183 | 149 | 164 | 357 | - |
| SRP as P (μg/L) | 36.2 | 72.1 | 11.0 | 11.0 | 40.2 | 56.8 | <1 | 40.1 | 30.5 | 169.2 | 10.9 | 47.1 | - | - |
| TKN (mg/L) | 1.7 | 1.5 | 1.2 | 2 | 2 | - | - | - | - | - | - | - | - | - |
| Total Dissolved Solids (g/L) | 0.2 | 0.1 | 0.1 | 0.1 | - | - | - | - | - | - | - | - | - | - |
| Total Nitrogen as N (mg/L) | - | - | - | - | - | 2.4 | 5.20 | 1.47 | 1.54 | 1.35 | 1.29 | 3.13 | 3.47 | 1.77 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 285.98 | <145 | <145 | <145 | 348 | <130 | 254 | 82 | 165 | 32 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 8 | <PQL | <PQL | <PQL | <PQL | <130 | 8 | 4 | 8 | 9 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | 2.97 | 1.89 | <0.4 | 2 | 3 | - | 3.49 | 0.12 | 0.49 | 0.38 | 0.18 | 2.19 | 2.66 | 0.53 |
| TN:TP ratio | - | - | - | - | - | 11 | 24 | 8 | 8 | 21 | 9 | 18 | 9 | - |
| pH | 7.8 | 7.3 | 8.3 | 7.8 | 7.7 | 7.8 | 8.3 | 7.9 | 7.9 | 8.4 | 8.0 | 7.8 | 7.6 | 7.2 |
| Alkalinity as CaCO3 (mg/L) | 83 | 48 | 65 | 66 | 57 | 77 | 72 | 119 | 104 | 85 | 75 | 86 | 76 | 112 |
| Silica as Si (mg/L) | - | - | - | - | - | - | - | - | 4.62 | 6.94 | 6.89 | 10.54 | - | - |
| Dissolved Organic Carbon (mg/L) | <7.6 | <7.6 | <7.6 | <7.6 | <6.4 | 8 | 7.70 | 9.63 | 6.51 | 8.16 | 11.60 | 11.32 | - | - |
| Inorganic Suspended Solids (mg/L) | 26 | 21 | 28 | 25 | 30 | 22 | 30 | 20 | 23 | 41 | 23 | 17 | 43 | 18 |
| Volatile Suspended Solids (mg/L) | 10 | <8 | 16 | 11 | <9 | <8 | 12 | 10 | 14 | 14 | 19 | 8 | 6 | 5 |
| Total Suspended Solids (mg/L) | 36 | 29 | 44 | 36 | 38 | 27 | 41 | 30 | 38 | 55 | 41 | 25 | 49 | 22 |
| Carlson Trophic State Index (Secchi)* | 82 | 87 | 78 | 82 | 82 | 79 | 80 | 75 | 80 | 82 | 76 | 82 | 82 | 77 |
| Carlson Trophic State Index (Chl a)* | 51 | 44 | 67 | 59 | 55 | 54 | 69 | 67 | 80 | 69 | 61 | 53 | 58 | 54 |
| Carlson Trophic State Index (TP)* | 78 | 82 | 79 | 80 | 82 | 81 | 84 | 79 | 80 | 79 | 76 | 78 | 89 | - |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |