Document Type



Middleborough High School, Middleborough, Massachusetts


Andrew Collins


Johnny H. Sederquist, Christopher S. Lunetta, Richard P. Damon, Ross Q. Zinkowski


The Nemasket River Watershed has an area of approximately 7.5 square miles. Historically this river has been used for commerce and transportation, fishing and recreation and, more recently, as a sink for wastewater effluent and urban runoff.

Our investigation was to determine what effects, if any, the runoff from “urban” Middleboro was having on the water quality just downstream from the town center and it’s aquatic life.

Our hypothesis was that the downstream location would be impacted from the increased runoff from the urban setting. The increase in pollution would be due to the increase in imperviousness of the urban landscape as well as the source of the pollution itself (automobiles, industry, etc.).

We looked at physical data such as flow, surface features, and nearby roads and highways. Chemical information was gathered in terms of nitrogen and phosphorous loading, temperature, dissolved oxygen, specific conductivity and pH. The biology of the stream was also analyzed in terms of benthic macroinvertebrate populations and diversity.

Our results were mixed. In terms of the chemical data we saw what we expected, an increase in soluble reactive phosphorous and nitrate nitrogen at the herring run (downstream location). The parameters that would be affected by this increase in pollution, like specific conductivity, also showed expected results. Other results were initially surprising, but after further research, made sense. Our macroinvertebrate data, for example, showed a healthier stream at our downstream location. We later attributed this to the greater variety of habitat and increased levels of dissolved oxygen at this site. The increase in dissolved oxygen we attributed to the small waterfall at this location.

Both our upstream and downstream locations could be considered healthy in terms of the aspects we studied. One of the reasons for this could be the relatively small size of “urban” Middleboro or that there is sufficient buffering by flora between the town and the river that remove some of the nutrients from the runoff.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.


Project Location