A gentle current flows downstream to meet other tributaries that vein a watershed. Rocks in the water teem with many types of tiny insects. That, we have learned, is a reliable indicator of a stream’s health.
The teacher of that lesson is Stroud Water Research Center, which sits on the near-pristine waters of White Clay Creek in Chester County, Pennsylvania. White Clay is perhaps the most intensively studied stream in the United States. What Stroud scientists have discovered there—and in major systems such as the Amazon—informs our understanding of water systems around the world. That is doubly true for northern Delaware, into which the White Clay flows.
In a world where competing interests vie for land use, such knowledge is invaluable.
And Stroud’s findings about the environment suggest that there is reason for both concern and optimism. “Streams have the ability to cleanse themselves,” says Stroud entomologist John Jackson—with a little help from those on dry land.
To that end, a host of government and private agencies have joined the battle to maintain water quality. More on that later. First, a look at the region, White Clay’s history and the uniqueness of Stroud.
The 107-square-mile White Clay Creek watershed stretches from southwestern Chester County to the western part of New Castle County above the Christina River. (A watershed, or basin, is that area of land on which a drop of water would flow, if unimpeded, to the stream within its boundaries.)
Just north of the state line, the creek’s three Pennsylvania branches form a main stem that merges with the three Delaware branches (Middle Run, Pike Creek and Mill Creek) and receives Red Clay Creek before emptying into the Christina at Churchman’s Marsh in Newport. In terms of its use, the White Clay is equal parts forested-open space, agricultural and urban-surburban. The latter category is growing.
The watershed takes its name from the sediment that once washed down from the Appalachians and created the region’s rich farmland. William Penn transformed a landscape of scattered Native American villages into communities that built mills to harness the stream’s power.
In the 1960s a DuPont Company-led bid to dam the White Clay met with stiff opposition that spawned the White Clay Creek Watershed Association, a staunch proponent of protection. Plans to build a dam and reservoir ultimately were abandoned, and in a generous turnabout, DuPont donated most of the land that has become the bi-state nature preserve and White Clay Creek State Park. “They are irreplaceable natural assets that will leave a lasting impact,” Jackson says.
The Stroud Center has made some tracks of its own since it was founded by the late W.B. Dixon “Dick” Stroud on his farm in Avondale, Pennsylvania, in 1966 at the urging of renowned freshwater researcher Ruth Patrick of the Philadelphia Academy of Natural Sciences. Two decades earlier, Patrick had conducted a series of studies in Lancaster County that showed a correlation between species diversity and a stream’s health. The concentration and variety of insects, in particular, was a barometer of water quality. At the Stroud Center, Patrick hired Tennessee Valley Authority scientist Robin Vannote to extend her work. He pioneered the next groundbreaking concept.
Vannote’s “river continuum” asserted that rivers and streams are not static but dynamic, that “studying a square meter of water to death” is just a snapshot, and only by analyzing the water from source to sea do you get a motion picture. “He put the big picture together, and stream research was never the same after that,” says current Stroud director Bernard Sweeney.
That picture grew richer when Sweeney and Vannote developed two more major concepts. “Thermal equilibrium” attributed the demise of aquatic life near such sites as dams and power plants to water temperature shifts that compromise reproductive potential. “Riparian buffers” demonstrated that forested streams not only filter harmful runoff, but add nutrients that bolster water health.
A bucolic stretch of White Clay Creek in Stroud’s backyard is the site that gave rise to the principles that revolutionized freshwater research, leading to management strategies aimed at staying ahead of environmental threats. Here and at more than a dozen locations throughout the watershed (including three in Delaware), Watershed Association volunteers collect insect samples that are processed by Stroud interns, who then compare the data. They are the foot soldiers; their superiors trace a chain of command all the way to Washington, D.C. If the water falters along the White Clay, it will not be for lack of oversight.
White Clay Creek is as decorated as a World War II hero. In addition to receiving two research designations from the National Science Foundation, it has been named an Exceptional Value Stream by the state of Pennsylvania and a Wild and Scenic River by Congress. Exceptional Value status, which applies only to part of its upstream waters, grants it a level of protection against development that would degrade the water. Wild and Scenic applies to the overall watershed in this case and gives White Clay the imprimatur of the National Park Service. Says Jackson, “Water ignores political boundaries.”
But it pays strict attention to hydrology. “All uses in the watershed can affect downstream,” Jackson points out.
That’s because the flow is inexorable. The White Clay Creek watershed is a subset of the 565-square-mile Christina River basin, which includes the river and the Brandywine Creek and Red Clay Creek watersheds. The Christina, in turn, is part of the Delaware River basin, which belongs to the Atlantic Ocean basin, and so on, up the geologic hierarchy. As the creek and river waters seek the ocean, migratory fish must move from saltwater to freshwater in order to reproduce. It is one of nature’s beautiful choreographies and is dependent on clean, stable water.
New Castle County draws 75 percent of its drinking water from the Christina River basin, much of it from surface water. Brandywine Creek, the largest single source of drinking water for Delaware, supplies Wilmington, the raw water quality benefiting from well-forested Brandywine Creek State Park upstream. Newark and other communities in New Castle get their water from White Clay Creek and groundwater sources both within and outside of the watershed. Downstate, the water supply is solely groundwater.
As development pressures mount, the White Clay is still clean and percolating. Its qualities are all the more impressive because of its proximity to major urban centers. “It’s not in Montana. It’s smack dab in the middle of a megalopolis,” says Jerry Kauffman, director of the Water Resources Agency at the University of Delaware. “The challenge is to balance growth with quality of life.”
That balancing act is shared by many towns, groups and agencies that are bolstered by the official designations and a sense of commitment. The national Wild and Scenic program restricts government projects and encourages, rather than mandates, local stewardship.
The locals have welcomed the task. After White Clay was selected in 2000, Newark, New Castle and Chester counties, and 11 Pennsylvania municipalities signed an agreement that calls for maintaining water quality and conserving open space.
“The whole idea of the partnership is that the federal government can leverage money with state and local money and people,” says Linda Stapleford, administrator for White Clay Creek Watershed Management Committee, which is funded by the National Park Service.
Not all of White Clay is wild and scenic, of course, but trout fisheries, bird and wildlife habitats, and assorted flora and fauna depend on a favorable ecology. Beyond the watershed, broader efforts are focusing attention on regional water systems.
One such program is the Christina Basin Clean Water Partnership, whose mission is to protect and restore. Funded by the federal Environmental Protection Agency, the partnership joins state and local governments in a busy slate of projects and programs that get right down to the homeowner level—for example, the use of special barrels to collect and recycle rainwater to reduce runoff. Another tactic to rein in the rain is the “smartyard” or rain garden, a section of lawn scooped to catch runoff and mulched to bear native plants, which require no pesticides, herbicides or watering. “Imagine if every property owner did that,” says Kauffman, who also serves as Delaware coordinator for the partnership.
Near Kauffmann’s office, White Clay Creek tributary Cool Run samples a slice of college life, and a 40-by-50 foot rain garden absorbs pollutants from building and parking lot runoff. Similar projects and larger undertakings such as stream reforestation help to reduce levels of nitrates, phosphorous and bacteria in the water, a goal also sought by projects that target farms. “The ultimate goal is, ‘Are we cleaning up the water?’” says Jan Bowers, the partnership’s Pennsylvania coordinator.
A manure management facility, for instance, may not be glamorous, but it’s clearly goal-oriented. The idea is to remove livestock waste at the barn and paddock before rainfall carries it to the stream. The Christina basin partnership can help farmers cut through the, uh, red tape. “By having the Pennsylvania Department of Environmental Protection involved, they understand what’s involved in the permit process,” says Bowers. Other protective strategies she promotes include stream bank fencing and restoring vegetation along denuded streams. EPA grants have been obtained for some of this work.
Even water, it seems, will follow the money. Says Bowers, “We identify funding and coordinate all of the relevant agencies at all levels of government so they don’t waste money. The sum is greater than the parts.”
But if water management is to be more than a zero-sum game, all the parts must be in good working order. In Delaware, where several companies deliver water to homes and businesses, the old structures are holding up and new ones are coming online.
Newark’s new reservoir—the city’s first—along the White Clay near Paper Mill Road—was scheduled to be fully operational by last month. The 313-million-gallon reservoir, which pumps water off-stream exclusively from White Clay Creek, provides an antidote to droughts but doesn’t leave downstream fisheries stranded. “We’ll try to keep it as full as we can,” says Roy Simonson, director of the Water and Wastewater Department. “It allows us, when the stream flow drops below our limits, to treat water from the reservoir and continue normal operations.”
The Newark Reservoir is the first sizable one built in Delaware since the venerable Hoopes reservoir was built a few miles outside Wilmington decades ago. A smaller, flexible source of water storage is United Water Delaware’s tidal capture structure along the White Clay at Stanton. It looks like a low-slung concrete dam, but has a rubber membrane that expands as much as 5 feet higher than the water level when it is pumped full (a real asset during periods of low flow). United is headquartered in Wilmington and serves several communities in northern New Castle.
Water, of course, doesn’t run only on the surface. Newark-based Artesian Water Company, which celebrated its centennial last year, delivers strictly groundwater across the state. The City of Newark maintains two well fields, the north installation drawing only from White Clay. Treating groundwater tends to be less elaborate than treating surface water, which is more affected by sediment.
We tend to take potable water for granted until a main busts and the tap turns brown. That burst of unpleasantness may be rectified quickly, but it’s sobering to realize that even modern treatment methods have limitations. That’s why protecting water at the source is critical. At the very least, it keeps treatment expenses down.
The threat of direct and indirect pollution is not likely to decrease, even for White Clay Creek. Armed with techniques based on decades of research, a lot of people are working to contain that threat.
Stroud’s reach now extends around the world (including a tropical station in Costa Rica), but White Clay Creek continues to be its principal laboratory. The bug counts still speak volumes, but there are more sophisticated activities afoot. An instrument called the isotope ratio mass spectrometer has enabled the center to become a time traveler.
The spectrometer can reveal, among other things, the diet of a 2-inch trout taken from a White Clay stream sample. The device then determines the source of that food, year-old spawning conditions, and how various elements got into the water. All of that forms a useful picture.
“The more we know about things that happened in the past, the better able we are to make adjustments in the present that will ensure the future health of the stream and its inhabitants,” writes director Sweeney.
And that gives water watchers some big fish to fry.
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