The Gist of the USGS

The Gist of the USGS

a Carolina Paddler Article

By Alton Chewning

Do you know what the letters USGS represent?  The answer is the United States Geological Survey.  On October 21, Carolina Paddler participated in a talk given by Lara Chapman, a USGS hydrologic technician, and sponsored by the Friends of the Lower Haw (FLOHA).  Lara did a wonderful job of explaining the workings of the Bynum gage on the Haw River.  Much of the information she shared is applicable to river gages across the US and in other countries.  In a later article, Carolina Paddler will recap the highlights of Lara’s talk on how river stage or height and discharge or streamflow, are measured.  For now, we’ll lay a little groundwork on the USGS.  At the end, for an added treat, we’ll pose a question to our readers, one often asked by Haw River paddlers.

The United States Geological Survey was formed in 1879.  Before this many efforts were underway to explore, map and codify the land and waters of the country.  The vast territories of the American West represented a particular challenge.  In 1878, four surveys were in progress, headed by illustrious scientists and explorers like Hayden, King, Wheeler and Powell.  John Wesley Powell is perhaps the best known, largely due to his leading an expedition on the first descent of the Grand Canyon and his prescient views on water management in the West. Other surveys were mapping parts of the East and North, and the extensive coastal regions.  Their goals were many: scientific, legal, commercial, and more.

Congress turned to the National Academy of Sciences to suggest ways of consolidating these disparate mapping efforts and after much lobbying and discussion, the United States Geological Survey was born in 1879, with the purpose of “classification of the public lands, and examination of the geological structure, mineral resources, and products of the national domain.”

Today, the USGS has many divisions conducting work in the US and abroad.  Often the departments associated with dramatic events like earthquakes and volcanoes receive the most attention.  The USGS has three major programs.  One is devoted to studying the nation’s geological structure and process, the assessment of mineral and energy resources and the investigation of geological hazards–the earthquakes and volcanoes.  A second emphasis is the National Mapping Program, which catalogs geological data in various forms.  A third focus, maybe the most interesting to paddlers like us, is the providing of hydrologic information and determining the best way to use and manage the nation’s water resources.

Narrowing our interest to the hydrology program, the South Atlantic Water Science Center (SAWSC) covers over 800 sites in North Carolina, South Carolina and Georgia. In North Carolina, SAWSC has offices in Asheville, Charlotte and Raleigh.  Their staff monitor various interests in our region:

-Floods, Droughts and Hurricanes

-Water Quality

-Water Availability and Use

-Groundwater and Streamflow Monitoring

-Coastal Science

-Advanced Capabilities and Research.

This article, “The Streamgaging Program in the South Atlantic Water Science Center” gives a good idea of what goes into providing information on the water resources in our area.

Our Bynum gage talk was conducted by the friendly and informative USGS hydrologic technician, Lara Chapman.  Lara works from the Raleigh office of SAWSC.  Lara points out, “The USGS is not the only entity that streamgages. State and local government organizations also run equipment and use software that is sometimes the same as the resources we use. I know the North Carolina Department of Environmental Quality (NCDEQ) is another organization that monitors water data.”

The Raleigh office has one of the most diverse water mission areas in the US.  Lara notes, “We cover everything from the rocky rivers of the Appalachians to the tidal waters and swamps of the coastal plane, endangered urban streams of the Triangle and Triad to the protected watersheds of the Roanoke.” The entire SAWSC participates in storm-tide monitoring but the Raleigh office, closest to the coast, does much of the groundwork.  The challenging geography has encouraged the Raleigh office to innovate and adapt diverse means of environmental monitoring.

Often Lara sits at a desk, compiling data or answering questions.  Other times she is knee deep in Crabtree Creek or Walnut Creek, measuring streamflow with a FlowTracker, a type of ADV (acoustic Doppler velocimeter).  She monitors these sites as part of Raleigh’s Flood Early Warning System (FEWS).  Urban streams have been a worrying source of flooding in the past and the need for an early warning system is unique to Piedmont cities like Raleigh and Charlotte.

If you like the sound of Flow trackers and bubblers, shaft encoders and CFS, be sure to catch the next article in Carolina Paddler, “Stages, Gages and Discharge.” Lara will explain the intimate workings of the Bynum stilling well and cableway and much, much more.

How Long?

We promised you a fun question.  Water coming down the Haw River originates in Forsyth, Guilford and Rockingham counties before arriving at the Bynum gage.  Many whitewater paddlers concentrate on the sections known as the Middle and Lower Haw for their swift water fun.  Rain falling in the immediate vicinity, Alamance and Chatham counties, has little effect on Haw streamflow.  There are two gages before the Haw River empties into Jordan Lake, one at the small town of Haw River (02096500) and the other downstream near the town of Bynum (02096960).  Hydrologists commonly call a burst or bubble of traveling water a “Slug.”  So, the question is:  How long does a slug of water take to travel from the Haw River gage to the Bynum gage?  Here is a hint.  The travel distance between the two gages is approximately 156,527 feet.