| Report Year: 2012 |
| Dog Creek Lake, O'Brien County |
| Summary Data Table |
| Parameter | 5/30/2012 | 7/17/2012 | 8/28/2012 | 2012 | 2011 | 2010 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 6.5 | 5.7 | 5.8 | 6.0 | 6.1 | 6.1 | 6.2 | - | 6.3 | 6.5 | 6.4 | 6.3 | 6.2 | 6.5 | 6.1 |
| Thermocline Depth (m) | Nil | 3.3 | 1.5 | N/A | 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) | 0.5 | 1.3 | 0.5 | 0.8 | 2.2 | 1.2 | 1.0 | - | 1.2 | 1.5 | 1.0 | 0.8 | 0.7 | 2.6 | 0.6 |
| Temperature(oC) | 18.5 | 28.3 | 23.8 | 23.5 | 24.6 | 23.7 | 22.8 | - | 16.3 | 22.9 | 21.4 | 21.6 | 20.6 | 21.8 | 24.8 |
| Dissolved Oxygen (mg/L) | 8.0 | 8.9 | 9.3 | 8.8 | 10.3 | 8.3 | 11.1 | - | 11.4 | 10.6 | 11.0 | 11.2 | 8.3 | 5.3 | 8.8 |
| Dissolved Oxygen Saturation (%) | 86 | 114 | 111 | 103.4 | 125.1 | 98.3 | 126.1 | - | 115.8 | 123.0 | 128.0 | 128.2 | 91.7 | 56.3 | 106.9 |
| Specific Conductivity (μS/cm) | 490.0 | 520.0 | 440.0 | 483.3 | 473.3 | 483.3 | 433.3 | - | 580.5 | 520.9 | 444.7 | 482.5 | 485.2 | 544.9 | 658.5 |
| Turbidity (NTU) | 23.8 | 3.9 | 21.0 | 16.2 | 8.2 | 3.8 | 6.3 | - | 14.3 | 30.8 | 20.9 | 14.7 | 20.8 | 24.7 | 15.8 |
| Chlorophyll a (μg/L) | 29.3 | 15.6 | 30.2 | 25.0 | 11.9 | 8.8 | 18.0 | - | 12.2 | 67.5 | 27.9 | 30.7 | 44.7 | 17.3 | 21.1 |
| Total Phosphorus as P (μg/L) | 78.7 | 40.7 | 47.9 | 55.7 | 37.0 | 44.9 | 55.8 | - | 24 | 61 | 97 | 129 | 123 | 152 | - |
| SRP as P (μg/L) | <10 | <10 | <10 | <10 | <11 | <8 | <9 | - | <1 | <1 | 3.2 | <1 | <1 | - | - |
| TKN (mg/L) | 1.4 | 1.1 | 1.3 | 1 | 2 | 1 | - | - | - | - | - | - | - | - | - |
| Total Dissolved Solids (g/L) | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | - | - | - | - | - | - | - | - | - | - |
| Total Nitrogen as N (mg/L) | - | - | - | - | - | - | 1.0 | - | 7.45 | 3.64 | 2.72 | 1.93 | 1.40 | 5.19 | 1.38 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 80.40 | 74.00 | 117.40 | 91 | <145 | <136 | <130 | - | 44 | 27 | 118 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 2 | 7 | 24 | <PQL | <PQL | <PQL | <130 | - | 2 | 3 | 14 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | 2.24 | 2.06 | 0.43 | 2 | 3 | 1 | - | - | 7.12 | 3.99 | 1.52 | 0.63 | 0.16 | 4.07 | 0.16 |
| TN:TP ratio | - | - | - | - | - | - | 19 | - | 312 | 84 | 31 | 14 | 11 | 40 | - |
| pH | 7.9 | 8.2 | 8.7 | 8.3 | 8.3 | 8.3 | 8.8 | - | 8.2 | 8.5 | 8.5 | 8.5 | 8.5 | 8.1 | 8.2 |
| Alkalinity as CaCO3 (mg/L) | 192 | 185 | 171 | 182 | 188 | 200 | 180 | - | 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) | 5.43 | 4.46 | 5.19 | 5 | <7.6 | <6.4 | <6.2 | - | 4.53 | 5.80 | 6.78 | 9.85 | 12.97 | - | - |
| Inorganic Suspended Solids (mg/L) | 17 | 5 | 7 | 10 | <5 | <4 | <4 | - | 2 | 3 | 5 | 8 | 3 | 5 | 9 |
| Volatile Suspended Solids (mg/L) | 7 | 3 | 9 | 7 | <8 | <9 | <8 | - | 5 | 6 | 7 | 9 | 8 | 6 | 4 |
| Total Suspended Solids (mg/L) | 25 | 8 | 16 | 16 | 6 | <5 | 10 | - | 7 | 10 | 11 | 16 | 9 | 12 | 13 |
| Carlson Trophic State Index (Secchi)* | 70 | 56 | 69 | 63 | 49 | 58 | 60 | - | 58 | 54 | 60 | 63 | 66 | 46 | 66 |
| Carlson Trophic State Index (Chl a)* | 64 | 58 | 64 | 62 | 55 | 52 | 59 | - | 55 | 72 | 63 | 64 | 68 | 59 | 61 |
| Carlson Trophic State Index (TP)* | 67 | 58 | 60 | 62 | 56 | 59 | 62 | - | 50 | 63 | 70 | 74 | 74 | 77 | - |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |