| Report Year: 2011 |
| Silver Lake (Worth), Worth County |
| Summary Data Table |
| Parameter | 6/8/2011 | 7/26/2011 | 9/7/2011 | 2011 | 2010 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 1.8 | 1.8 | 1.7 | 1.8 | 1.7 | 1.8 | 1.6 | 1.7 | 1.6 | 2.2 | 1.9 | 1.4 | 1.9 | 2.0 |
| Thermocline Depth (m) | Nil | 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) | 0.1 | 0.2 | 0.4 | 0.2 | 0.2 | 0.3 | 0.2 | 0.3 | 0.3 | 0.2 | 0.5 | 0.2 | 0.5 | 0.3 |
| Temperature(oC) | 24.7 | 29.2 | 22.0 | 25.3 | 22.3 | 23.8 | 24.0 | 20.5 | 25.1 | 23.9 | 22.9 | 24.7 | 24.3 | 23.8 |
| Dissolved Oxygen (mg/L) | 6.3 | 15.6 | 12.8 | 11.6 | 9.3 | 9.5 | 13.6 | 13.2 | 9.2 | 10.4 | 10.2 | 9.6 | 13.3 | 11.6 |
| Dissolved Oxygen Saturation (%) | 76 | 204 | 146 | 141.9 | 106.5 | 111.8 | 161.3 | 146.0 | 111.7 | 123.5 | 119.8 | 117.6 | 161.4 | 137.7 |
| Specific Conductivity (μS/cm) | 270.0 | 220.0 | 190.0 | 226.7 | 236.7 | 256.7 | 244.9 | 267.6 | 308.0 | 254.3 | 315.7 | 339.7 | 238.1 | 271.2 |
| Turbidity (NTU) | 118.3 | 59.1 | 29.4 | 68.9 | 34.0 | 30.7 | 125.8 | 68.9 | 43.1 | 237.3 | 46.0 | 87.3 | 51.1 | 86.0 |
| Chlorophyll a (μg/L) | 130.2 | 75.1 | 51.8 | 85.7 | 60.8 | 51.7 | 107.7 | 79.5 | 285.4 | 101.5 | 19.9 | 64.0 | 32.8 | 69.0 |
| Total Phosphorus as P (μg/L) | 358.2 | 168.0 | 103.3 | 209.8 | 195.5 | 138.7 | 237 | 157 | 177 | 186 | 182 | 198 | 122 | - |
| SRP as P (μg/L) | <11 | <11 | <11 | <11 | <8 | <9 | <1 | <1 | <1 | 1.4 | 2.0 | 1.6 | - | - |
| TKN (mg/L) | 2.3 | 3.9 | 2.4 | 3 | 4 | - | - | - | - | - | - | - | - | - |
| Total Dissolved Solids (g/L) | 0.2 | 0.1 | 0.1 | 0.1 | - | - | - | - | - | - | - | - | - | - |
| Total Nitrogen as N (mg/L) | - | - | - | - | - | 2.6 | 1.96 | 2.17 | 1.24 | 2.44 | 3.58 | 1.98 | 1.56 | 2.22 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 263.19 | <145 | <145 | <145 | 170 | <130 | <26 | 53 | 67 | 48 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 25 | <PQL | <PQL | <PQL | <PQL | <130 | 7 | 10 | 7 | 17 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | <0.4 | <0.4 | <0.4 | <0.4 | <0.5 | - | 0.22 | 0.12 | 0.21 | 0.27 | 0.42 | 0.23 | 0.17 | 0.31 |
| TN:TP ratio | - | - | - | - | - | 19 | 10 | 14 | 6 | 13 | 20 | 11 | 14 | - |
| pH | 8.3 | 9.5 | 9.6 | 9.1 | 9.2 | 9.3 | 9.4 | 9.3 | 8.8 | 9.3 | 8.5 | 8.9 | 9.3 | 8.4 |
| Alkalinity as CaCO3 (mg/L) | 133 | 100 | 74 | 103 | 104 | 113 | 124 | 123 | 129 | 107 | 100 | 120 | 97 | 122 |
| Silica as Si (mg/L) | - | - | - | - | - | - | - | - | 5.22 | 6.52 | 4.48 | 7.38 | - | - |
| Dissolved Organic Carbon (mg/L) | 9.25 | <7.6 | 9.41 | 9 | 10 | 14 | 18.84 | 19.37 | 17.45 | 19.14 | 19.20 | 22.16 | - | - |
| Inorganic Suspended Solids (mg/L) | 48 | 9 | <5 | 19 | 15 | 10 | 25 | 19 | 32 | 13 | 13 | 9 | 13 | 18 |
| Volatile Suspended Solids (mg/L) | 92 | 44 | 30 | 55 | 42 | 23 | 45 | 41 | 41 | 35 | 21 | 31 | 13 | 47 |
| Total Suspended Solids (mg/L) | 140 | 53 | 31 | 75 | 57 | 34 | 79 | 61 | 72 | 48 | 35 | 29 | 34 | 65 |
| Carlson Trophic State Index (Secchi)* | 96 | 81 | 75 | 82 | 81 | 77 | 85 | 78 | 80 | 83 | 69 | 81 | 69 | 79 |
| Carlson Trophic State Index (Chl a)* | 78 | 73 | 69 | 74 | 71 | 69 | 77 | 74 | 86 | 76 | 60 | 71 | 65 | 72 |
| Carlson Trophic State Index (TP)* | 89 | 78 | 71 | 81 | 80 | 75 | 83 | 77 | 79 | 80 | 79 | 80 | 73 | - |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |