Dan's Papers - June 15, 2007 - Solar Bees Hope To Save Water Mill Pond

Mill Pond, in the center of Water Mill is ill - and only a swarm of something called SolarBees can save it. In a joint effort by the Peconic Land Trust and the Friends of Lake Nowedonah, four SolarBee water-circulating devices have been installed to try to cure Mill Pond's ailments. Perhaps due to storm water runoff from nearby lawns and fields, Mill Pond has become a eutrophic lake. The term "eutrophic" is used to describe any body of water with an excess of nutrients and, subsequently, an overabundant plant and algae population. The same nutrients that make grass, crops and ornamental plants grow faster, such as phosphorus and nitrogen, can be deadly to a lake or pond ecosystem. Because lakes are stagnant (for the most part) they usually have a lower dissolved oxygen content than bays and oceans, as the only way oxygen can be dissolved into the water is if it is created by underwater plants or exchanged at the surface due to water turbulance. When there are too many nutrients (fertilizers) present in the water, once the plants have used up all the nutrients they need to grow, the excess nutrients begin to support abnormal populations of algae. Plants, including algae, have a life cycle just like all other living things. So when there are too many plants in a lake, dead plant matter and algae spores settle on the bottom of the lake. The process of decay utilizes oxygen to convert the dead plant matter back into useable nutrients - this means that, in a eutrophic lake like Mill Pond, not only is there an overabundance of nutrients -- but the microorganisms helping to break down the overload of dead plant matter on the bottom are using up all of the oxygen in the pond. Once dissolved oxygen levels drop, Mill Pond will experience massive fish and bird loss, resulting in the death of the entire ecosystem in and around the pond.

Luckily, the Peconic Land Trust and the Friends of Lake Nowendawah, and their four SolarBees, have buzzed by to clean up the pond. Although there are quick-fix chemical methods that can help keep harmful nutrients trapped in the sediment, the SolarBees are the only remedy for eutrophication that does not involve chemicals or use of a power source. The SolarBees are powered by solar panels, which charge a battery that connects to a motor. As the motor turns a propeller, stagnant, oxygen-deprived water from the bottom of the pond is sucked up a long tube and ejected at the surface of the water. This not only creates water turbulence, which discourages algae blooms by making it more difficult for the algae to settle on the surface of the water and get sunlight, but also allows the water from the bottom of the pond to have contact with the surface of the water, where it can absorb oxygen from the air. In addition, the SolarBees can also be equipped to take surface water and shoot it directly into the bottom waters of the pond, thus speeding the process of oxygenation. This constant circulation and aeration of water can bring dissolved oxygen levels up to an optimum level (known as saturation level) in as little as one week.

So, what's the catch? For now, the SolarBees are being rented on a trial basis. If they can heal the pond, the Friends of Lake Nowendawah have pledged to raise the funds necessary to purchase the devices. Since there is no one point source of pollution, such as a drainpipe, pouring nutrient-rich waste water into Mill Pond, it would be almost impossible to prevent eutrophication by halting the use of fertilizers and other harmful substances around the pond. If the SolarBees work, the health and livelihood of the entire Mill Pond ecosystm will be dependant upon the Friends of Lake Nowendawah and the Peconic Land Trust's ability to maintain the SolarBee devices. If they succeed, Mill Pond will once more be a home for bass, ospreys and egrets and a source of pleasure and relaxation for the community.