Prior Lake - Spring Lake Watershed District 2009 Water Quality ...

SSWCD staff worked collaboratively in order to monitor all 34 monitoring sites in a few hours.By monitoring many sites at nearly the same time, potential “hot spots” (i.e. potentiallysignificant source of pollution) can be identified in the watershed. See Table 1 for example andrefer to Appendix 2 and 3 for more detailed synoptic monitoring results and figures.Site #Turbidity(FNU)pH(units)Temperature(°C)SpecificConductivity(µs)DissolvedOxygen(mg/L)EstimatedFlow(CFS)6 7.40 7.70 9.00 885 7.71 1.507 18.30 8.06 9.11 755 9.88 2.0011 37.10 7.42 9.12 704 6.51 0.0514 3.70 7.60 8.92 586 6.30 1.0016 0.00 7.46 9.26 606 6.8017 10.10 7.53 9.43 789 5.00 2.0019 297.20 7.70 9.24 533 5.70 1.5021 28.50 8.15 10.03 61 9.99 0.2023 24.20 7.67 9.48 310 8.51 1.0025 9.50 7.69 10.10 327 8.60 2.0026 2.30 8.04 10.10 492 9.89 0.2027 11.50 7.74 9.41 416 8.76 0.2028 1194.00 7.92 9.45 208 10.20 2.5029 3.30 7.97 9.81 592 8.18 0.2030 4.00 7.68 10.19 371 7.14 3.5031 0.0032 2.80 7.68 12.07 711 5.74 0.7533 14.60 7.73 10.36 123 10.2636 5.40 8.21 12.97 444 8.7738 7.50 7.40 9.55 511 7.45 1.0040 101.10 7.71 9.64 626 8.69 1.00Table 1. Synoptic monitoring results after large rain event on October 6, 2010. Highlighted cells indicate that sampleexceeded the 25 NTU turbidity standard. All other parameters appear to be in good condition.c. Sampling ParametersDissolved oxygen, pH (when possible 2 ), specific conductance, turbidity, and temperature weremonitored using the Hydrolab MS5 sonde. These are basic parameters that can be used toindicate whether pollution is likely in the stream. For instance, high turbidity may indicate highsediment loads from agriculture or urban run‐off. Low dissolved oxygen may indicate anabundance of algae. High conductivity may be an indicator of road salt intrusion. By identifying2 Only one of the four sondes used had the capability to monitor pH.Page 5 of 15