Reducing Your Nitrogen Footprint

Dr K was asked a question by  students from Greenwich Country Day school doing a project on nitrogen in Long Island Sound.

Q: What can I do to reduce the amount of nitrogen that goes into Long Island Sound?

Dr. K:

This is a great question, and it’s one that I get asked pretty frequently. The things that we can do to reduce our impact on climate change are very well discussed and publicized, but much less so for nitrogen loading. Some of the actions are similar, but some are very different. Here’s a few suggestions:

• Use less water: Water is the enemy of sewage treatment plants. Recent upgrades to our treatment facilities have made them very efficient at removing nitrogen from wastewater, but the amount of nitrogen they can remove is directly related to how long they can keep the water in treatment. The only way to change this is to increase the amount of treatment tank space they have (which costs taxpayers a lot of money), or reduce the amount of water we send them (which can actually save you money). Things like reduced flow spigots for sinks (about $5) and showerheads ($20-$50), and dual flush retrofit kits for toilets (about $20) can pay for themselves very quickly, especially if you factor in the cost of heating the water. Washing machines and dishwashers also use a lot of water, so only running full loads and purchasing high efficiency appliances helps a lot.
• Eat less meat: The amount of nitrogen in our waste is proportional to how much meat we eat. As a general rule, Americans eat more meat than our bodies can process; about 270 lbs/year, roughly twice the USDA recommendation (see http://www.choosemyplate.gov/ for more information on this). If the average for everyone living within 50 miles of the Sound went from 270 to 135 lbs/year of meat, this would reduce the load on our treatment facilities by about 300 million pounds of nitrogen per year. That doesn’t even consider the impact of meat farming, which is substantial.The impact on the Sound from this would be similar to what we’ve achieved by spending about $4 Billion on sewage treatment plant upgrades.
• When it comes to lawns, Don’t Think Green: Use less fertilizer and reduce the amount of your lawn that’s planted with turf grass. Native plants and shrubs store and process more nitrogen than turf grass does, and require less water and fertilizer. Installing rain barrels to store water and using this to water your lawn/garden also helps a lot by reducing water load on treatment facilities during peak flow times.

If you want to see how your daily activities influence your nitrogen footprint, and how your footprint compares to other Americans, and people around the world, you can check out the interactive Nitrogen Footprint calculator at www.n-print.org.

Jason Krumholz, aka Dr. K, spent three years as the NOAA liaison to EPA’s Long Island Sound Office. Dr. Krumholz received his doctorate in oceanography at the University of Rhode Island Graduate School of Oceanography.

Editor’s Note: The opinions expressed in this blog are those of the author. They do not reflect EPA or NOAA policy, endorsement, or action, and EPA or NOAA do not verify the accuracy or science of the contents of the blog.