Pollution

2017-11-08 - 07:18:00 Kat Kavanagh commented

Is this film still there? It could be a number of things, and could be pollution or natural. Someone always told me to look for other signs: unnatural smells, dead fish. If the issue is gone, you can close it in the status below :) Here's some details from http://www.shorelandmanagement.org/quick/wq.html What causes surface scum on a lake? There are various causes of surface scums on a lake or pond. Look more closely to determine what is on the water’s surface. An oily film or yellow-green dust on the surface of a lake make it look contaminated but, in most cases, nothing is wrong. In fact, something natural is probably occurring. An oily film in mid-summer may be caused by organic compounds from nearby wetlands, rotting vegetation, or insect cases that were concentrated along the shore by wind after a hatch. Insects can hatch at any time from ice-out in the spring until mid-September. As the insect cases decompose, they sometimes produce an oily film. Yellow-green dust floating on the surface in late spring and early summer is probably pollen from nearby trees. In contrast, a scum from an algal bloom is green to blue-green, might have an oily sheen that resembles a motor oil slick, and can form a thick, soupy mass on the surface of the water.