July 27, 2001

NC State Coastal Watershed Research Benefits Land Management Planners

Some dexterity is required for Francois Birgand, PhD graduate student
in the Department of Biological and Agricultural Engineering, to collect
a sediment sample from a drainage canal in Washington County, NC.
Birgand completed his studies in 2000 and is now a researcher with
CEMAGREF in France.

Hurricane Floyd showed North Carolinians the vulnerability of coastal areas to flooding from major storm events.  The presence of functional watersheds in the coastal plain is an essential protection for natural and human communities because watersheds act as high water buffers as well as water quality preservers.  Research projects that contribute information about healthy watershed systems are important components of coastal planning for the state.

NC State researcher Dr. R. Wayne Skaggs, William Neal Reynolds Professor and Distinguished University Professor of biological and agricultural engineering, heads a team that is conducting long-term research that will help coastal managers make informed land-use decisions.  One of Skaggs’ projects, the Cumulative Impacts Watershed Project in Washington County, has been going on for several years.  The project objective is to develop computer models to determine the impacts of coastal land use and management practices on hydrology and pollutant loads at the watershed level.

Unanswered questions about the effects of land usage on watersheds abound.  For example, what are the consequences of rainfall amounts, nitrogen cycling in the soil, field size, pesticide load, water flow rates and hydrology on watershed health?  Skaggs and his research team have developed mechanistic, mathematical computer models that are designed to help answer some of these questions.

According to Skaggs, these models, when carefully field-tested over time, can provide a predictive tool that can be used by land managers to evaluate nonpoint source pollution in places such as the Neuse River basin.  Nonpoint source pollution is environmental contamination that cannot be traced to a single source, such as a factory discharge pipe.

Currently Skaggs’ research team is evaluating and comparing six different methods of applying these models on a production scale to a large watershed in Washington County.  The scientific research methods are labor-intensive and challenging but yield detailed results.  Simplified methods are much easier to use but give more approximate results.  Part of the current effort is directed to sorting out the costs and benefits of the various methods.

The research team, which includes graduate and undergraduate students, post-doctoral researchers, faculty and technicians, is gathering information from a test watershed that includes farmland in production as well as managed and natural forested areas, and they are using the data collected to model the hydrological cycle of the watershed over time.  These data should enable Skaggs’ team to determine the predictive value of the models, with the ultimate goal of providing a simplified, practical instrument for land management decisions.

According to Skaggs, “We now have tools that are more than just promising; we’ve developed and tested them on a 25,000-acre experimental watershed.  Application of these tools would be very useful to an agency that is trying to decide where to spend money to reduce nitrogen loading in coastal streams and estuaries.” 

At this stage the most valuable information will result from application of model methodologies to actual watersheds rather than from more developmental research.  The eventual result of this essential field-testing will be to enable management agencies to make informed decisions based on sound data about where best to focus their efforts and funds to preserve the integrity of watersheds — an issue of vital importance for the future of North Carolina’s water resources.

-- rudd --

Media Contacts:  R. Wayne Skaggs, 919/515-6739, wayne_skaggs@ncsu.edu, Linda E. Rudd, 919/515-3848, linda_rudd@ncsu.edu