I forgot to mention that I also spent some time with my net when water testing on the Wapsipinicon on Tuesday in honor of the Benthic macroinvertebratesworkshop I attended last last weekend. Unfortunately between the silt-sand bottom and the high water level, macroorganisms were hard to find. I actually found more of them in my puppy's plastic pool filled with rain water. I have seen a water boatman in there for one. Maybe I will work on identifying organisms form the pool!
I read my IOWATER bacteria plates today. Yesterday I got a lab reading of 2100 E. Coli bacteria per 100 ml of water. Of the 3 plates I read today using the IOWATER test, one had 59 colonies (*33 for my dilution factor=1947 colonies per 100 ml of water), one had 71 colonies (*33=2343) and one had 97 (*33=3201). That last one is suspect. Coliform bacteria are pink, white,teal,green, blue or purple. But E. Coli (from fecal matter and potentially disease-causing) are only the blue or purple colonies. A lot of the blue colonies on that last plate seemed to have a teal tint, so I did not know if I should count them or not. If I average all 3, I get 2497. If I average only the first 2, I get an average of 2145, close to my lab test of 2100. Either way, I am well above the safe level of 235 colonies per 100 ml of water.
I like to see that the IOWATER test bacteria results are similiar to the more accurate lab results because my students will have to rely on the IOWATER bacteria test accuracy since it is the only one we will be using.
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