The Conservation Law Foundation (CLF) filed a petition with the Environmental Protection Agency on Monday that is aimed at protecting the Neponset River from stormwater pollution, following upticks in algae blooms caused by pollution.

The petition requests that the EPA use its authority to require large properties contaminating the river with runoff to obtain Clean Water Act permits. CLF also filed an identical petition with respect to the Mystic River.

“Properties have been given free rein to dump toxic pollutants into the Mystic and Neponset Rivers for too long,” said Heather Govern, the director of CLF’s Clean Air and Water program. “Communities surrounding the Mystic and Neponset already see far more than their share of pollution, and toxic algae outbreaks only add insult to injury. It’s time EPA hold these polluters accountable and ensure that residents have access to clean and healthy rivers.”

Cyanobacteria, more commonly known as blue-green algae because of their color, are the result of too much phosphorus in the rivers. Exposure to cyanobacteria blooms has been linked to neurodegenerative diseases like ALS, and the algae are also harmful to pets and wildlife.

During rain or snowmelt, water runoff from urban streets, parking lots, and construction sites carry oil, grease, sediment, phosphorus, and other pollutants into the Neponset. CLF’s petition targets big box stores, strip malls, and major apartment complexes surrounding the river that they say are main sources of those pollutants.