| Report Year: 2009 |
| Five Island Lake, Palo Alto County |
| Summary Data Table |
| Parameter | 6/4/2009 | 7/8/2009 | 2009 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Lake Depth (m) | 6.4 | 5.6 | 6.0 | 5.9 | 5.6 | 6.2 | 6.3 | 6.0 | 5.2 | 5.9 | 5.4 |
| Thermocline Depth (m) | Nil | Nil | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Secchi Disk Depth (m) | 0.5 | 0.6 | 0.5 | 0.4 | 0.5 | 0.6 | 0.7 | 0.5 | 0.6 | 1.4 | 0.8 |
| Temperature(oC) | 18.5 | 23.8 | 21.2 | 23.7 | 24.2 | 24.6 | 22.6 | 21.9 | 23.3 | 23.2 | 24.8 |
| Dissolved Oxygen (mg/L) | 8.0 | 7.0 | 7.5 | 7.4 | 8.9 | 9.9 | 9.7 | 9.6 | 8.3 | 8.8 | 8.4 |
| Dissolved Oxygen Saturation (%) | 86 | 83 | 84.1 | 87.5 | 106.5 | 121.4 | 112.6 | 110.8 | 97.0 | 103.4 | 101.0 |
| Specific Conductivity (μS/cm) | 430.0 | 450.0 | 440.0 | 464.7 | 498.8 | 478.2 | 452.0 | 470.7 | 476.5 | 444.3 | 418.8 |
| Turbidity (NTU) | 19.2 | 16.7 | 17.9 | 41.2 | 55.2 | 28.2 | 32.4 | 29.7 | 30.2 | 35.2 | 14.7 |
| Chlorophyll a (μg/L) | 17.0 | 18.0 | 17.5 | 38.0 | 34.0 | 95.5 | 45.4 | 30.8 | 32.0 | 17.4 | 23.3 |
| Total Phosphorus as P (μg/L) | 75 | 80 | 77 | 122 | 66 | 97 | 77 | 69 | 91 | 77 | 140 |
| SRP as P (μg/L) | - | 1 | 1 | 1 | 2 | 1 | 1 | 2 | 4 | - | - |
| Total Nitrogen as N (mg/L) | 0.45 | 1.55 | 1.00 | 2.39 | 2.50 | 4.19 | 4.32 | 2.85 | 1.79 | 2.66 | 1.58 |
| (Phenate)Ammonia Nitrogen (NH3 + NH4+) as N (μg/L) | 256 | 54 | 155 | 260 | 78 | 108 | 101 | - | - | - | - |
| (Phenate)Ammonia Nitrogen (NH3) as N (un-ionized)(μg/L) | 31.7 | 6.3 | 19.0 | 29.8 | 6.9 | 14.1 | 14.3 | - | - | - | - |
| Nitrate + Nitrite (NO3 + NO2) as N (mg/L) | 0.62 | 0.12 | 0.36 | 1.18 | 1.08 | 2.63 | 2.33 | 1.62 | 0.50 | 1.51 | 0.26 |
| TN:TP ratio | 6 | 19 | 13 | 24 | 37 | 47 | 54 | 40 | 20 | 62 | 12 |
| pH | 8.6 | 8.4 | 8.5 | 8.4 | 8.4 | 8.4 | 8.6 | 8.5 | 8.3 | 8.2 | 8.2 |
| Alkalinity as CaCO3 (mg/L) | 173 | 161 | 167 | 173 | 190 | 183 | 140 | 126 | 163 | 135 | 180 |
| Silica as Si (mg/L) | - | - | - | - | - | 3.55 | 3.23 | 2.35 | 3.25 | - | - |
| Dissolved Organic Carbon (mg/L) | 9.73 | 6.99 | 8.36 | 20.14 | 5.90 | 6.70 | 23.14 | 12.22 | 14.12 | - | - |
| Inorganic Suspended Solids (mg/L) | 13 | 14 | 13 | 25 | 12 | 15 | 11 | 15 | 17 | 10 | 12 |
| Volatile Suspended Solids (mg/L) | 7 | 10 | 9 | 21 | 11 | 15 | 13 | 10 | 9 | 7 | 8 |
| Total Suspended Solids (mg/L) | 20 | 24 | 22 | 46 | 23 | 30 | 23 | 24 | 26 | 16 | 20 |
| Carlson Trophic State Index (Secchi)* | 72 | 67 | 69 | 73 | 69 | 69 | 66 | 70 | 69 | 56 | 63 |
| Carlson Trophic State Index (Chl a)* | 58 | 59 | 59 | 66 | 65 | 75 | 68 | 64 | 65 | 59 | 61 |
| Carlson Trophic State Index (TP)* | 66 | 67 | 67 | 73 | 65 | 70 | 67 | 65 | 69 | 67 | 75 |
| *Index values generally range between 0 and 100, with increasing values indicating more eutrophic conditions. |