Wednesday, June 26, 2013
Milky White Mystery--The Sequel
Last week's post about Harry's Brook turning milky white has a sequel. Returning to the scene of the milky mystery with my canine assistant, Leo, I came upon two young men in waders, peering with great concentration at the contents of two plastic trays. The water in the trays contained what signs of aquatic life Harry's Brook might hold. Tom McKeon works for Americorps and is based this summer at the Stony-Brook Millstone Watershed Assoc., where he has the title Watershed Ambassador. Peter Zampella works for the Pinelands Preservation Alliance, south of here.
You can tell a lot about a stream by what sorts of aquatic life it holds. Some species are more sensitive to water pollution than others. Whereas a chemical test of the water will give a snapshot of the water quality that particular day, an inventory of the aquatic species able to survive there will reflect water quality over a longer period. Cumulative stress factors like low oxygen and periodic toxic spills will leave only the less sensitive species.
If there were toxins in whatever turned the creek milky white the week before, the more sensitive aquatic species might die off, and not show up in the samples of water Tom and Peter were scrutinizing.
As they do at the many other sites in the area that they monitor, they also measured water temperature, and did a rough calculation of water flow using a sophisticated device known as a rubber ducky. There are specially made floats for the purpose, but the rubber duckies work just as well or better.
Only rubber duckies with the proper paraphernalia need apply for the job. Peter explained that the ducks with goggles, etc. are a bit heavier, giving them the optimum density for measuring the speed of water flow.
Tom agreed to take my sample of last weeks milky water to the Watershed, where it could potentially get transferred to the state DEP offices for testing. We noticed that the white color comes from lots of white particles suspended in the water.
The water quality verdict? Not great, though not surprising, considering that the water comes from a network of pipes that drain Princeton's downtown business district.