Runoff in Narragansett Bay

By Bradley Labonte

 

NARRAGANSETT-Nutrient runoff from plant fertilizer has gotten into Narragansett Bay and has now affected the marine life.

 

Dr. Rebecca Robinson is a scientist who studies Narragansett Bay and its chemistry. She spoke with a group of University of Rhode Island students about the impact of runoff into the Bay.

 

“Were worried about this because were changing the chemistry of the Earth faster than we see in the geological record,” said Robinson. “On the other hand, though, we are not the first organisms to change the chemistry of the Earth.”

 

Plants and photosynthesis changed the chemistry of the Earth about 2 billion years ago. Photosynthetic plants created an oxic atmosphere and people could not live on an Earth without oxygen, but people are changing it in a different way.

 

Plants need specific nutrients to conduct photosynthesis and those nutrients are carbon, nitrogen and phosphorus, which are in fertilizer. These nutrients then runoff into the Bay.

 

“All the nutrients are coming in from the northern part of the Bay and their causing these diatoms and all these photosynthetic organisms to just grow like gangbusters,” said Robinson.

 

This is good in the sense that their creating energy and plant material for fish to eat. But, the excess of plants have drawn a lot of the oxygen out of that part of the Bay, which kills fish.

 

“That is one of the biggest problems that has plagued Narragansett Bay and it has sent a lot of people trying to understand it,” said Robinson.

 

According to Robinson, the state now regulates the amount of nitrogen waste water treatment facilities are allowed to discharge seasonally (May-October).

 

“Rhode Island has invested millions of dollars to reduce the amount of nutrients that go into Narragansett Bay,” said Robinson. “We’ve created these huge storage tanks, so that during huge rain events, nothing goes directly into the Bay.”

 

The state of Rhode Island set a goal to reduce the nutrient input into the Bay, by 50% of the 2005 levels, by 2015. And they have already met those goals.