nitrogen pollution

Around the Water Cooler: Can Innovations Solve Our Nutrient Problem?

By Lahne Mattas-Curry

Nitrogen is an integral part of proteins, the building blocks of life. But in excess, like anything else, it can have negative effects. In fact, too many nutrients, including nitrogen, can cause depletion of available oxygen in surface waters, toxic algal blooms, hypoxia and acid rain.

The consequences aren’t pretty. Excess nitrogen threatens our air and water quality as well as disrupts the health of our communities, people and land. In other words, some plants and animals can’t live in this kind of environment. I’ve written about this problem before. For example, check out this post on seagrasses.

Nutrient pollution is a problem that affects many areas in the United States, including the Gulf of Mexico, the Chesapeake Bay, and New England’s Narragansett Bay.

To help combat this overwhelming nutrient problem Cleantech Innovations New England  is providing awards to applicant teams of up to $130,000 as part of the i6 Green Challenge, funded by EPA in partnership with the U.S. Department of Commerce and the Department of Energy.

The funds will be awarded to develop ground-breaking and affordable technologies that can reduce nitrogen discharge from septic systems by 95%. (A high proportion of New England communities and more than 20% of U.S. Residents rely on septic systems). In addition, these new technologies should be able to recover nutrients (nitrogen (N), phosphorus (P) and preferably potassium (K)) from the wastewater and/or also create energy.

The technologies must be scalable and affordable, with retrofits to existing septic systems costing in the range of $5,000 to $10,000, and no more than $25,000 for new installations. Of course, on-site nutrient monitoring should also be considered in order to monitor performance.

For more information and to apply for the award, please visit Cleantech Innovations New England. The deadline to apply is January 18th, 2013.

About the Author: Lahne Mattas-Curry works with EPA’s Safe and Sustainable Water Resources research team and is a frequent “Around the Water Cooler” contributor.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.

Wondrous Wetlands

By Tarlie Townsend

What’s your favorite ecosystem? Rainforest? Tundra?

Scenic wetlandsAfter talking with EPA postdoctoral researcher Amanda Nahlik, I’d answer “wetlands”— those water-saturated areas like swamps, bogs, and marshes. They’re so much more than the dreary, monster-infested settings of the movies. In fact, they do great things for us!

Here are just three examples of benefits (“ecosystem services”) we all get from wetlands:

  • Wetland as barrier (storm protection): They reduce the size and speed of waves hitting the shore, helping protect coastal communities during storms.
  • Wetland as sponge (flood amelioration): Amanda recounted one firsthand example: it was springtime in Ohio, the snow had just melted, and heavy rains were imminent. Scientists at The Ohio State University (OSU) Olentangy River Wetland Research Park (where Amanda worked), were concerned that their downstream campus might flood. The solution: manage the nearby experimental wetlands by installing weirs so the wetlands could hold and absorb the floodwater. It worked! The wetland functioned like a sponge, and OSU went flood-free. After the storm, the scientists removed the weirs and slowly released the water back into the river.
  • Wetland as kidney (water purification): Wetlands even clean our water! Myriad wetland organisms absorb contaminants and excessive nutrients (primarily nitrogen and phosphrous) cleaning the water flowing through them.

Here’s where Amanda’s current research comes in. One substance “cleaned” by wetlands is excess nitrogen (primarily from fertilizer runoff). How much nitrogen is absorbed, and how that correlates with other wetland conditions, isn’t well understood. But it matters, because wetlands across the world—under stress from physical destruction, climate change, pollution, and more—are changing, compromising their ability to provide ecosystem services in the form of nitrogen removal.

Existing methods of measuring nitrogen removal are both expensive and time-intensive. And because the amount of denitrification varies, numerous rounds of testing are necessary.

Amanda and colleague J. Renée Brooks may have a solution: comparing the ratio of different nitrogen isotopes (Nitrogen-15 and Nitrogen-14) to measure how much denitrification occurs in a given wetland over time. If more nitrogen-15 is found in the soil, they reason, the wetland is reducing nitrogen pollution and its harmful effects—a good way to help assess the condition of the wetland, and the “ecosystem services” it provides.

Amanda is in the preliminary phase of testing soil isotope measurements in order to develop an indicator of denitrification. So far, the results look good, and could lead to a quick, easy, and inexpensive way to measure how much nitrogen is being removed. Learning about the research also gave me better appreciation for the value of wetlands—my new favorite ecosystem!

About the Author: Tarlie Townsend recently completed an internship in EPA’s Office of Research and Development.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.