| Report Year: 2009 |
| Lake Pahoja, Lyon County |
| Summary Data Table |
| Parameter | 7/7/2009 | 6/2/2009 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 7.9 | 7.4 | 7.7 | - | 7.5 | 7.8 | 8.1 | 8.1 | 7.9 | 8.4 | 8.2 |
| Thermocline Depth (m) | 2.1 | 4.8 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Secchi Disk Depth (m) | 0.5 | 3.9 | 2.2 | - | 3.7 | 1.6 | 0.9 | 0.9 | 1.4 | 2.0 | 0.6 |
| Temperature(oC) | 24.7 | 19.5 | 22.1 | - | 16.7 | 22.9 | 21.4 | 21.5 | 24.4 | 22.3 | 25.1 |
| Dissolved Oxygen (mg/L) | 15.2 | 9.5 | 12.3 | - | 10.8 | 10.2 | 11.9 | 10.4 | 11.4 | 9.9 | 11.4 |
| Dissolved Oxygen Saturation (%) | 183 | 103 | 143.0 | - | 111.1 | 118.3 | 137.5 | 119.4 | 136.8 | 113.0 | 137.2 |
| Specific Conductivity (μS/cm) | 570.0 | 670.0 | 620.0 | - | 730.3 | 623.6 | 623.9 | 669.0 | 766.4 | 723.5 | 609.9 |
| Turbidity (NTU) | 220.9 | 1.3 | 111.1 | - | 3.8 | 16.8 | 28.8 | 19.1 | 38.0 | 29.5 | 74.7 |
| Chlorophyll a (μg/L) | 80.0 | 4.0 | 42.0 | - | 7.2 | 152.8 | 24.5 | 22.8 | 34.6 | 17.0 | 80.7 |
| Total Phosphorus as P (μg/L) | 116 | 78 | 97 | - | 32 | 94 | 83 | 83 | 59 | 82 | 356 |
| SRP as P (μg/L) | - | 46 | 46 | - | 1 | 3 | 21 | 7 | 1 | - | - |
| Total Nitrogen as N (mg/L) | 2.79 | 1.51 | 2.15 | - | 8.55 | 3.93 | 4.38 | 2.34 | 4.66 | 6.95 | 1.69 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | - | 180 | 180 | - | 127 | 139 | 214 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | - | 41.7 | 41.7 | - | 8.2 | 40.1 | 17.6 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | 0.35 | 0.60 | 0.48 | - | 7.65 | 3.54 | 2.81 | 1.12 | 3.43 | 5.65 | 0.19 |
| TN:TP ratio | 24 | 19 | 22 | - | 270 | 45 | 55 | 29 | 91 | 86 | 6 |
| pH | 9.1 | 8.9 | 9.0 | - | 8.4 | 8.6 | 8.7 | 8.6 | 8.7 | 8.4 | 8.8 |
| Alkalinity as CaCO3 (mg/L) | 212 | 301 | 257 | - | 276 | 236 | 211 | 191 | 219 | 174 | 241 |
| Silica as Si (mg/L) | - | - | - | - | - | 2.06 | 1.96 | 1.33 | 1.33 | - | - |
| Dissolved Organic Carbon (mg/L) | 7.32 | 7.61 | 7.47 | - | 5.39 | 7.42 | 7.40 | 10.62 | 9.98 | - | - |
| Inorganic Suspended Solids (mg/L) | 7 | - | 7 | - | 3 | 4 | 4 | 9 | 7 | 5 | 7 |
| Volatile Suspended Solids (mg/L) | 18 | 4 | 11 | - | 3 | 8 | 8 | 7 | 7 | 3 | 11 |
| Total Suspended Solids (mg/L) | 25 | 4 | 14 | - | 6 | 13 | 13 | 16 | 15 | 7 | 19 |
| Carlson Trophic State Index (Secchi)* | 72 | 41 | 49 | - | 41 | 54 | 62 | 61 | 55 | 50 | 67 |
| Carlson Trophic State Index (Chl a)* | 74 | 44 | 67 | - | 50 | 80 | 62 | 61 | 65 | 58 | 74 |
| Carlson Trophic State Index (TP)* | 73 | 67 | 70 | - | 54 | 70 | 68 | 68 | 63 | 68 | 89 |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |