| Report Year: 2009 |
| Dog Creek Lake, O'Brien County |
| Summary Data Table |
| Parameter | 6/2/2009 | 7/7/2009 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 6.2 | 6.2 | 6.2 | - | 6.3 | 6.5 | 6.4 | 6.3 | 6.2 | 6.5 | 6.1 |
| Thermocline Depth (m) | 2.9 | 3.5 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Secchi Disk Depth (m) | 0.8 | 1.5 | 1.2 | - | 1.2 | 1.5 | 1.0 | 0.8 | 0.7 | 2.6 | 0.6 |
| Temperature(oC) | 20.1 | 24.2 | 22.1 | - | 16.3 | 22.9 | 21.4 | 21.6 | 20.6 | 21.8 | 24.8 |
| Dissolved Oxygen (mg/L) | 13.8 | 8.4 | 11.1 | - | 11.4 | 10.6 | 11.0 | 11.2 | 8.3 | 5.3 | 8.8 |
| Dissolved Oxygen Saturation (%) | 152 | 100 | 126.5 | - | 115.8 | 123.0 | 128.0 | 128.2 | 91.7 | 56.3 | 106.9 |
| Specific Conductivity (μS/cm) | 440.0 | 410.0 | 425.0 | - | 580.5 | 520.9 | 444.7 | 482.5 | 485.2 | 544.9 | 658.5 |
| Turbidity (NTU) | 7.1 | 3.6 | 5.3 | - | 14.3 | 30.8 | 20.9 | 14.7 | 20.8 | 24.7 | 15.8 |
| Chlorophyll a (μg/L) | 38.0 | 3.0 | 20.5 | - | 12.2 | 67.5 | 27.9 | 30.7 | 44.7 | 17.3 | 21.1 |
| Total Phosphorus as P (μg/L) | 47 | 46 | 47 | - | 24 | 62 | 97 | 128 | 124 | 150 | 361 |
| SRP as P (μg/L) | - | - | - | - | 1 | 1 | 12 | 2 | 13 | - | - |
| Total Nitrogen as N (mg/L) | 1.13 | 0.90 | 1.02 | - | 7.45 | 3.64 | 2.72 | 1.93 | 1.40 | 5.19 | 1.38 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 24 | 23 | 24 | - | 50 | 26 | 124 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 4.8 | 5.8 | 5.3 | - | 2.1 | 3.1 | 15.1 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | 0.26 | - | 0.26 | - | 7.13 | 4.00 | 1.53 | 0.63 | 0.16 | 4.11 | 0.17 |
| TN:TP ratio | 24 | 20 | 22 | - | 313 | 86 | 31 | 14 | 11 | 40 | 4 |
| pH | 8.8 | 8.8 | 8.8 | - | 8.2 | 8.5 | 8.5 | 8.5 | 8.5 | 8.1 | 8.2 |
| Alkalinity as CaCO3 (mg/L) | 198 | 178 | 188 | - | 226 | 200 | 154 | 161 | 186 | 154 | 205 |
| Silica as Si (mg/L) | - | - | - | - | - | 5.54 | 4.34 | 4.19 | 3.05 | - | - |
| Dissolved Organic Carbon (mg/L) | 6.69 | 6.12 | 6.41 | - | 4.53 | 5.80 | 6.78 | 9.85 | 12.97 | - | - |
| Inorganic Suspended Solids (mg/L) | 6 | 2 | 4 | - | 4 | 3 | 5 | 8 | 3 | 5 | 9 |
| Volatile Suspended Solids (mg/L) | 9 | 4 | 6 | - | 4 | 7 | 7 | 9 | 8 | 6 | 4 |
| Total Suspended Solids (mg/L) | 15 | 5 | 10 | - | 7 | 10 | 11 | 16 | 9 | 12 | 13 |
| Carlson Trophic State Index (Secchi)* | 63 | 54 | 58 | - | 58 | 54 | 60 | 63 | 66 | 46 | 66 |
| Carlson Trophic State Index (Chl a)* | 66 | 41 | 60 | - | 55 | 72 | 63 | 64 | 68 | 59 | 61 |
| Carlson Trophic State Index (TP)* | 60 | 59 | 60 | - | 50 | 64 | 70 | 74 | 74 | 76 | 89 |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |