Richmond, Virginia — The American South (Mid-Atlantic)
City Locks River Gauge
How it works:
The gauge is a tube of air with a standard amount of pressure inside. How much the river water rises up the tube determines how much more the air is compressed. That increased pressure can be scaled to indicate the river level.
In the beginning, people just read a numbered gauge, but it was hard to read when there were waves and impossible to observe when there was a flood. You can still see it – on the wall, beside the canal door, at the entrance.
Today the measurements are taken electronically every hour and sent via satellite to the National Weather Service and the US Geological Service. You can access the information at http://waterdata.usgs.gov/va/uv
Why you should care:
River height tells you the amount of water flowing downstream – a measure which affects shipping, recreational boating and fishing. During floods, the gauge indicates how much water will inundate farmland and shoreline businesses downstream and whether to operate the floodwall gate upstream. Note, however, that the river level number is a reference point only and does not mean that the water is that deep at all places.
Tides impact the river level too. The gravity
There is another gauge at the Huguenot Bridge. It measures the river entering Richmond at the Fall Line - the stretch of rocks and rapids between Bosher Dam and the Mayo Bridge. There are other gauges located up and down the river.
A Brief History:
•1882 monitoring began here by reading the numbered scale attached to the canal entrance
•1957 a structure was built and an electronic system was installed using a float in a tube
•1969 everything was destroyed in the flood -- from Hurricane Camille (28.6 feet)
•1971 the highest flood ever recorded took place -- from Hurricane Aqnes (36.5 feet)
•1985 the most recent big flood -- from Hurricane Juan (30.7 feet)
•2005 the float gauge was replaced by the pressurized system
…and now you are here!
Erected by Friends of James River Park.
Location. 37° 31.52′ N, 77° 25.241′ W. Marker is in Richmond, Virginia. Marker can be reached from the intersection of Dock Street and Pear Street, on the right when traveling east. Touch for map. Located in Great Shiplock Park. Marker is at or near this postal address: 2803 Dock Street, Richmond VA 23223, United States of America.
Other nearby markers. At least 8 other markers are within walking distance of this marker. Rocketts Landing and Wharf / Confederate Navy Yard / Powhatan’s Birthplace (here, next to this marker); Coffer Dams (within shouting distance of this marker); Great Ship Lock (within shouting distance of this marker); Rocketts Landing (within shouting distance of this marker); Confederate Navy Yard (within shouting distance of this marker); a different marker also named Great Ship Lock (within shouting distance of this marker); a different marker also named Great Ship Lock (about 300 feet away, measured in a direct line); Welcome to Chapel Island (about 400 feet away). Touch for a list and map of all markers in Richmond.
Also see . . . James River at City Locks at Richmond, VA (USGS 02037705). U.S. Geological Survey National Water Information System (Submitted on December 14, 2012, by Bernard Fisher of Mechanicsville, Virginia.)
Categories. • Industry & Commerce • Waterways & Vessels •
Credits. This page was last revised on June 16, 2016. This page originally submitted on December 14, 2012, by Bernard Fisher of Mechanicsville, Virginia. This page has been viewed 453 times since then and 36 times this year. Photos: 1, 2. submitted on December 14, 2012, by Bernard Fisher of Mechanicsville, Virginia.