N-Sink Online Tool

A New Way of Looking at Nitrogen Pollution

Extension educators from the Center for Land Use Education and Research (CLEAR) and their partners have developed an online tool that helps land owners and land use decision makers better understand the direct connection between their land and nitrogen (N) pollution in coastal waters.

The tool, called “N-Sink,” is the result of a multi-year collaboration of CLEAR with the University of Rhode Island Coastal Institute and the EPA Atlantic Coastal Environmental Sciences Division Laboratory in Narragansett, Rhode Island.

map with a lot of red areas on it where there is nitrogen pollution
The particle tracking tool (shown here is the lower Pawcatuck River) allows users to click on a point within a watershed and, within seconds, generate its flow path to the coast and get an estimate of how much N (relatively speaking) will be delivered.

Nitrogen (N) pollution is a big threat to water quality, especially in coastal areas like Long Island Sound. Excess nutrients like N can fuel algal blooms that rob the waters of oxygen, directly harm marine life, and damage habitat. As a result, much attention has been paid to N pollution by the scientific community, including the development of many models designed to explore the transport and fate of N in our coastal watersheds. Most of these models focus on N “loadings,” i.e., estimating the amount of N being put into the system from sources like agricultural and lawn practices, septic systems, and atmospheric deposition from acid rain. Thus the focus is on what the total load of N is to the receiving water body, and what the impacts to that water body might be.

N-Sink uses a different approach that shifts the focus to the land within the watershed, rather than the receiving waters. The end result is a series of maps that help to provide specific geographic focus on which areas in the watershed are at the most risk for sending N to the coast (see maps, right). To do this, N-Sink uses particle tracking technology in concert with stream network data that includes information on nitrogen “sinks”—areas in the landscape that help to remove N from the system, like wetlands, riparian areas, lakes, and ponds. Depending on the sinks that it encounters along its journey to the coast, a unit of N could have very different fates, and thus very different impacts on water quality. For instance, a pound of N in one area of the watershed could be transported almost entirely to the coast, while another pound of N, applied just a short distance away, could take a different pathway through the stream network that results in the removal of a significant amount of N via sinks.

“One contribution of N-Sink is that it focuses on critical sink areas like wetlands and riparian corridors, which will hopefully lead to intensified efforts to protect or even restore these areas,”

says Extension Educator Chet Arnold. “Also, since the geographic specificity of N-Sink ties any location in the watershed to its likelihood of contributing N pollution, we think it can be useful both for land use planners when determining future uses, and land owners when discussing management practices on land already in use.”

The CLEAR team has created a state-of-the-art interactive N-Sink application where you can explore the maps for the entire Long Island Sound coast of Connecticut.

Article by Chet Arnold

CLEAR Webinars In April

aerial view of Connecticut River and agricultural fieldsWEDNESDAY, April 21, 2021 1:00 PM – 1:30 PM
Chet Arnold, UConn Dept. of Extension & CLEAR
Qian Lei-Parent, UConn Dept of Extension & CLEAR
Land use planners, property owners, and watershed managers need all the help that they can get to reduce the impacts of nitrogen (N) pollution on waterways, particularly in coastal areas. CLEAR, URI and EPA have developed an online tool, N-Sink, that provides some of this help. N-Sink identifies areas within a watershed that are likely to contribute N to coastal waters, and other areas that are likely to remove N from the system before it gets to the coast. The tool now covers all of the coastal watersheds of Connecticut and Rhode Island. This 30-minute webinar will describe the workings behind the tool, demonstrate the new N-Sink web app, and initiate a discussion on ways that the information might be used.
city street in Connecticut
Photo: CEDAS

WEDNESDAY, April 28, 2021 1:00 PM – 2:00 PM

Laura Brown, Community & Economic Development Educator, UConn Extension
Sadie Colcord, Associate Director of Partnerships, AdvanceCT
Kristen Gorski, Economic Development Coordinator, Town of West Hartford, and President, CT Economic Development Association (CEDAS)
Many communities struggle to find a comfortable balance between the desires of the business community, the desires of residents, and the requirements of existing zoning regulations and regulatory processes. In this session, the presenters will offer suggestions for finding this balance by exploring topics including: the role of economic development in the local land-use regulatory process; what companies are really looking for in a community; ensuring your community is ready for a desired development project; why and how to say no to a development proposal; and how to strike the right balance between zoning enforcement (which sometimes means saying no to business) while simultaneously encouraging the right kind of projects for your community. Attendees will learn about the Best Practices in Land Use and Economic Development Program, created by the Connecticut Economic Development Association and the Connecticut Chapter of the American Planning Association, and how to utilize the program as a tool for balancing economic development and planning.