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From a cable car above the Rappahannock River, USGS technician Cathy Wright checks one of 10 water samples USGS hydrologic technicians Cathy Wright (in basket) and Amy Jensen collect water samples from the Rappahannock River off River Road in Spotsylvania. |
By RUSTY DENNEN
Cathy Wright spent several hours in a small cable car suspended 30 feet above the Rappahannock River below Motts Run.
For Wright and her colleague Amy Jensen, both hydrologic technicians with the U.S. Geological Survey, it's all in a hot day's work.
"I can't complain. During the fall and the spring, it's just awesome to be out here," Jensen said with a smile, waiting on the shore Tuesday morning off River Road in Spotsylvania County.
Meanwhile, Wright lowered a bucket to the water to scoop up a sample every 10 feet across the river's width.
Ten liters of water--one liter for each spot along the river--was put on ice for transport to the state lab, the Division of Consolidated Laboratory Services, in Richmond.
There, the samples are checked for nutrients and sediment. Nutrients such as nitrogen and phosphorus are the No. 1 water-pollution issue facing the Chesapeake Bay.
Those chemicals contribute in summer to massive algae blooms that deplete oxygen, needed by other marine creatures, when they die and decompose.
Erosion and runoff from farm fields and developed areas upstream are a major water-quality problem in the Rappahannock and Rapidan.
Wright and Jensen started their sampling on the Rapidan earlier yesterday, using the same routine.
The USGS takes monthly water samples at 12 sites on major rivers across the state. That's done either from bridges or cable crossings.
The federal agency also takes samples on the Pamunkey, Mattaponi, North Anna, north and south forks of the Shenandoah, Chickahominy, Appomattox, York and James rivers, said Ken Hyer, a hydrologist in Richmond who supervises the program. Samples are taken during high water following storms.
"This is all being done in collaboration with the Virginia Department of Environmental Quality because they are members of the Chesapeake Bay Program," Hyer said. The bay program is a regional conservation partnership.
The DEQ does similar monitoring at 18 other river sites.
"This gives us, overall, a detailed picture of what is going on" Hyer said.
The USGS has been taking the samples since 1985.
"For example, at the Rappahannock station, there has been a significant decrease in total [nutrients]. That's good news. It means we're making progress, but we're not there yet," he said.
Reasons for the reduction are unclear, but they are probably related to agricultural, homeowner and development practices.
The USGS is the federal agency for Earth science, focusing on biology, geography, geology, geospatial information and water.
The agency maintains water gauges on the Rappahannock and Rapidan, at the Fredericksburg cable crossing site and in Culpeper and Remington.
The gauges offer timely information about river flow, water temperature and other factors.
Real-time river information: water data.usgs.gov/va/nwis/uv/?site_no= 01668000Rusty Dennen: 540/374-5431
Email: rdennen@freelancestar.com
