|Rosman Gaging Station|
Gaging stations are facilities used by hydrologists to
monitor streams, rivers, lakes or other bodies of water. Instruments at these stations collect
information such as water height, discharge and water chemistry and temperature.
The US Geological Survey has gaging
stations at thousands of locations across the United States. Measurements from these stations are useful
for flood prediction, water management, and recreation and navigation
Transylvania County has gaging
stations on the French Broad River at Rosman and Blantyre. There was also a gaging station on the south
side of the French Broad River at Calvert until 1955. On the Davidson River there is a gaging
station located downstream from Sycamore Flats.
|Calvert Gaging Station|
The small concrete structures at
Calvert and Davidson River were constructed using WPA funds in 1934. The buildings are quite small, about 3 feet
square. Both have an art deco look to
their poured concrete exteriors. They
contain vents with slats or louvers and narrow metal doors. A small window allows some light into the
Calvert structure as well.
The Rosman station was built in 1935
but is much plainer. The small frame structure,
with a simple wooden walkway, is raised on a cinder block foundation. A trapdoor in the foundation provides access
to the measuring panel.
The Blantyre station is a cinderblock
building constructed in the 1950s.
Access is from metal ladder attached to the bridge and then across a
wood and metal suspension walking bridge.
Measuring sticks or staff gages, which
were basically giant rulers, measured the height of the water above a fixed
point. Stage values could be converted into
discharge values for the stream.
The old gages would have been read manually.
Flood stage at Rosman is 9 feet. The highest recorded stage was 14.95 feet on
October 4, 1964. The drainage area
covers nearly 68 square miles.
|Blantyre Gaging Station|
At Blantyre the drainage area is 296
square miles and flood stage is 16 feet.
The record at Blantyre is 27.10 feet on July 16, 1916.
The drainage area for the Davidson
River site covers 40 square miles. Flood
stage is 9 feet, with the highest recorded stage at 12.08 on August 17, 1994.
Today measurements are
computerized. Data is recorded at
15-to-60-minute intervals and transmitted to USGS offices every 1 to 4 hours,
although it may be more frequent during critical events. Information is available online at
waterdata.usgs.gov/nwis/rt for the Blantyre, Rosman and Davidson River sites.
Photographs and information for this
column are provided by the Rowell Bosse North Carolina Room, Transylvania
County Library. Visit the NC Room during
regular library hours (Monday-Friday) to learn more about our history and see
additional photographs. For more
information, comments or suggestions contact Marcy at [email protected] or 828-884-3151 x242.