Eutrophication In Indian Lake

A Common Problem

One general issue plaguing lakes in the New England area is eutrophication. Eutrophication is when excess nitrates and phosphates are introduced into the ecosystem of a lake, typically be human activity. These added chemicals make the water very nutrient rich, benefiting the growth of certain plants more than others. Aggressive growth of certain species can overtake and choke out other plants and aquatic wildlife. This effect can cause an ecosystem to alter drastically. Many of these changes affect recreational use of the lake and impair its aesthetics [4]. The introduction of nitrates and phosphates into Indian Lake was likely caused by runoff from a local street or storm drain, along with debris and dirt particles from the bordering highway.

Ecological Effects

Lake eutrophication triggers a chain of events. The excess nitrates and phosphates create ideal conditions for the growth of select plants. These plants begin to grow excessively, spreading and becoming denser every year. As they take over water clarity decrease along with the levels of dissolved oxygen in the water. Decreased light and oxygen levels together result in death of many aquatic animals. Fish and other gilled animals that rely on filtering oxygen out of the water suffocate. As these animals perish, they don't feed on the aquatic plants that caused the problem, allowing them to grow even more aggressively. The decline in the lake's fish population also results in the relocation of other local animals, including waterfowl like ducks and herons, to new food sources . In addition to the destruction of the local ecosystem, as the excess nitrates and phosphates build up, algae blooms will begin to form. Some of these algae blooms can be poisonous to humans and other animals.

Recreational Problems

The effect of eutrophication on recreation is a growing nuisance. As plants continue to grow more aggressively, they begin to take up more of any particular water column. Swimmers have a hard time swimming through dense aquatic plants. Boats are more likely to get entangled in the plants as they move, becoming stuck and ruining their engines.

Indian Lake

Though Indian Lake is already suffering the effects of eutrophication and is infested with invasive weeds, it is not beyond recovery. These studies recommend simple measures that aim to prevent further devastation of the local ecosystem.


Developed as Part of a WPI Sponsored Project
In Affiliation with The Indian Lake Watershed Association
Worcester, MA 2013