This summer, LEA is working with an army of volunteers who are collecting samples to help determine the impact of septic systems on our lakes. As most homeowners know, wastewater from our homes and camps flows into a concrete septic tank where solids settle out and then the liquids continue on to a buried field of perforated pipes or chambers where the remaining water can filter into the ground (at least that is how it is supposed to work!). But many systems are old and they may not be functioning properly. This could lead to wastewater, which contains both nutrients that fertilize algae and human pathogens, getting into the lakes and ponds where we swim. To help determine if this is happening, volunteers are collecting water samples up and down the shores of lakes. These samples are then analyzed for the presence of optical brighteners. Optical brighteners are compounds found in some paper products and laundry detergents to make paper and fabrics “whiter and brighter”. Their presence alone in a sample of water is not a health issue, but it does indicate that septic systems may not be properly treating wastewater. This could mean that other, more harmful contaminates are getting in our lakes.
The first round of sampling that was done in July revealed about one-third of all samples taken tested positive for optical brighteners. The initial findings are alarming, but all the results are not in yet – the second round of sampling is almost complete and samples are being analyzed. Volunteers revisited sites that tested positive and also sampled new locations to increase the coverage. We hope to expand this project next year with simultaneous testing for other indicators of waste contamination, like E.coli, to better quantify the extent of the problem. Please stay tuned and remember to pump your septic tank!