| Report Year: 2011 |
| Windmill Lake, Taylor County |
| Summary Data Table |
| Parameter | 6/14/2011 | 8/1/2011 | 9/12/2011 | 2011 | 2010 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 4.2 | 4.0 | 4.3 | 4.2 | 4.5 | 4.5 | - | - | 5.0 | 5.0 | 5.0 | 5.0 | 5.0 | 4.9 |
| Thermocline Depth (m) | Nil | 2.7 | 2.1 | 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 | 0.4 | 0.4 | 0.3 | 0.3 | 0.4 | - | - | 0.9 | 0.7 | 1.1 | 1.1 | 0.6 | 0.4 |
| Temperature(oC) | 21.3 | 29.9 | 24.4 | 25.2 | 24.6 | 24.2 | - | - | 24.6 | 22.9 | 24.4 | 26.2 | 24.1 | 26.2 |
| Dissolved Oxygen (mg/L) | 7.0 | 9.6 | 11.2 | 9.3 | 6.7 | 7.0 | - | - | 10.0 | 7.0 | 10.8 | 8.5 | 7.0 | 9.9 |
| Dissolved Oxygen Saturation (%) | 79 | 127 | 135 | 113.6 | 79.8 | 82.8 | - | - | 120.1 | 81.2 | 130.5 | 104.9 | 81.4 | 122.6 |
| Specific Conductivity (μS/cm) | 270.0 | 220.0 | 240.0 | 243.3 | 230.0 | 243.3 | - | - | 270.1 | 292.5 | 278.9 | 220.4 | 190.2 | 194.1 |
| Turbidity (NTU) | 67.7 | 28.6 | 39.6 | 45.3 | 35.9 | 39.0 | - | - | 52.6 | 128.4 | 118.7 | 25.6 | 38.7 | 44.4 |
| Chlorophyll a (μg/L) | 44.4 | 53.8 | 50.8 | 49.7 | 39.2 | 28.3 | - | - | 196.6 | 26.6 | 20.4 | 131.0 | 65.7 | 39.5 |
| Total Phosphorus as P (μg/L) | 101.6 | 82.2 | 89.8 | 91.2 | 102.7 | 89.5 | - | - | 102 | 103 | 94 | 113 | 162 | - |
| SRP as P (μg/L) | <11 | <11 | <11 | <11 | <8 | <9 | - | - | 2.3 | 27.1 | 3.4 | 1.9 | - | - |
| TKN (mg/L) | 2.1 | 1.4 | 0.8 | 1 | <0.5 | - | - | - | - | - | - | - | - | - |
| Total Dissolved Solids (g/L) | 0.2 | 0.2 | 0.2 | 0.2 | - | - | - | - | - | - | - | - | - | - |
| Total Nitrogen as N (mg/L) | - | - | - | - | - | 1.5 | - | - | 1.25 | 1.42 | 1.14 | 1.94 | 1.55 | 2.07 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 469.60 | <145 | <145 | 148 | 152 | 208 | - | - | 39 | 92 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 10 | <PQL | <PQL | <PQL | <PQL | <130 | - | - | 11 | 7 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | <0.4 | <0.4 | <0.4 | <0.4 | <0.5 | - | - | - | 0.17 | 0.16 | 0.12 | 0.16 | 0.33 | 0.12 |
| TN:TP ratio | - | - | - | - | - | 17 | - | - | 12 | 14 | 15 | 17 | 10 | - |
| pH | 7.7 | 8.5 | 8.8 | 8.3 | 8.3 | 8.2 | - | - | 8.6 | 8.2 | 8.4 | 8.3 | 8.2 | 8.0 |
| Alkalinity as CaCO3 (mg/L) | 121 | 96 | 87 | 102 | 96 | 106 | - | - | 127 | 128 | 92 | 91 | 79 | 94 |
| Silica as Si (mg/L) | - | - | - | - | - | - | - | - | 3.11 | 5.06 | 3.79 | 3.68 | - | - |
| Dissolved Organic Carbon (mg/L) | <7.6 | <7.6 | <7.6 | <7.6 | 7 | 7 | - | - | 5.69 | 7.22 | 11.63 | 11.05 | - | - |
| Inorganic Suspended Solids (mg/L) | 47 | 7 | 19 | 25 | 15 | 22 | - | - | 13 | 8 | 4 | 7 | 10 | 10 |
| Volatile Suspended Solids (mg/L) | 11 | 15 | 12 | 13 | 11 | 11 | - | - | 11 | 6 | 7 | 14 | 12 | 12 |
| Total Suspended Solids (mg/L) | 59 | 22 | 31 | 37 | 26 | 34 | - | - | 25 | 14 | 11 | 15 | 22 | 22 |
| Carlson Trophic State Index (Secchi)* | 83 | 75 | 72 | 76 | 78 | 73 | - | - | 62 | 66 | 58 | 58 | 67 | 72 |
| Carlson Trophic State Index (Chl a)* | 68 | 70 | 69 | 69 | 67 | 63 | - | - | 82 | 63 | 60 | 78 | 72 | 67 |
| Carlson Trophic State Index (TP)* | 71 | 68 | 69 | 69 | 71 | 69 | - | - | 71 | 71 | 70 | 72 | 78 | - |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |