esearchers believe that the Neuse River’s water
quality is higher when the public understands preven-tion and treatment concepts relating to nitrogen (N) losses from farm fields.
That’s why N.C. Cooperative Extension’s Neuse Education Team (NET) promotes the Core Creek Project in Craven County, northwest of New Bern.
Harmful nitrogen reaches the Neuse River as nitrates from fields via shallow groundwater, man-made and natural drainage systems. The nitrates are mobile because crops use only 60 to 70 percent of applied N.
Not even decreasing fertilizer on a field guarantees 100 percent N uptake. Some remains soil-bound and ends up in the river.
To keep our water supply cleaner, researchers have developed mechanical interventions, known as water-quality best management practices (BMPs), to lessen the amount of N reaching Neuse.
In one such effort in 2000, charter NET member David Hardy initiated the 5-year, $1.3 million Core Creek Project, a Clean Water Management Trust Fund-backed water-quality improvement effort for the Neuse.
Hardy, who left the project in 2001 to become NET’s Neuse Crop Management Project coordinator, said the project’s goals were to “restore degraded lands for ability to protect and restore water quality” and to “acquire wetland easements for restoration of riparian buffers and wetlands.”
While the project remains focused on Core Creek’s headwaters, Charlie Humphrey, the N.C. Cooperative Extension environmental education specialist who assumed Hardy’s duties in 2003, substantially expanded the project’s boundaries and BMP implementation down- and upstream.
NET researchers originally studied only the creek’s headwaters, where it’s easier to detect and monitor pollution sources and BMP effectiveness. But Core Creek’s downstream section drains more land and hosts more potential pollution sources.
“The project’s principal objective,” Humphrey says, “remains the restoration of degraded waters. We continue to monitor the watershed and collect and analyze water-quality details at 60 stream locations.”
To restore those degraded waters, the project implements and evaluates an agricultural BMP system. That includes BMPs for nutrient management, controlled drainage and wetlands restoration, with riparian buffers and vegetative filter strips along the creek’s headwaters.
Humphrey cites completed nutrient management plans for the project’s originally designated acreage and on 22,000 more acres for a total of 27,000 acres, and a digitized mapping system to help growers better analyze and manage records.
“Agriculture producers in the Core Creek Watershed are in compliance with the Neuse Rules,” Humphrey notes. “The producers in Core Creek received nitrogen reduction credits for nitrogen management plans and controlled drainage structures that were implemented on their farms.”
Controlled drainage uses water control structures (WCS) such as a flash board riser to raise or lower a drainage outlet’s elevation, which adjusts the water level elevation of the area draining to the structure and outlet. Work continues on controlled drainage BMPs, Humphrey says.
“We originally estimated that it would require 100 field-scale and 20 farm-scale structures to impact 3,000 acres of cropland,” he says. “To date, we’ve identified locations and have landowner or operator consent for more than 100 water-control structure installations that will impact more than 4,000 acres.”
Designs are complete on 85 of the more than 100 WCS, and 55 WCS are installed, he says.
“We hope to complete the design and installation of the remaining structures over the next 18 months,” Humphrey says. To that end, he’s pursuing a no-fee time extension from the CWM Trust Fund.
In the project’s wetlands restoration BMP portion, Humphrey has landowner consent to restore a 24-acre pasture to wetlands. The appraisal, Phase I Environmental Report, survey and title work are complete, and attorneys are drafting a conservation easement. An N.C. State University Biological and Agriculture Engineering Department team will complete the restoration design work.
“When the restoration occurs, we will have pre- and postrestoration water quality data,” he says. “Also, we have contacted some other landowners about conservation easements and wetlands restoration. With adequate time, we could further pursue those tracts as well.”