What is a reach?
“Reach” can have slightly different meanings, depending on how it is used.
A reach is a section of a stream or river along which similar hydrologic conditions exist, such as discharge, depth, area, and slope. It can also be the length of a stream or river (with varying conditions) between two streamgages, or a length of river for which the characteristics are well described by readings at a single streamgage.
In practical use, a reach is just any length of a stream or river. The term is often used by hydrologists when they’re referring to a small section of a stream or river rather than its entire length.
Related Content
Is there a way to get alerts about streamflow conditions?
Why does the USGS use the spelling "gage" instead of "gauge"?
How can I obtain river forecasts (flood forecasts)?
Why might USGS streamflow data be revised?
Where can I get real-time and historical streamflow information?
How do we benefit from USGS streamgages?
Reach-scale monitoring and modeling of rivers--Expanding hydraulic data collection beyond the cross section
For over 125 years, the U.S. Geological Survey streamgage network has provided important hydrologic information about rivers and streams throughout the Nation. Traditional streamgage methods provide reliable stage and streamflow data but typically only monitor stage at a single location in a river and require frequent calibration streamflow...
Forbes, Brandon T.; Bunch, Claire E.; DeBenedetto, Geoffrey; Shaw, Corey J.; Gungle, Bruce
StreamStats, version 4
IntroductionStreamStats version 4, available at https://streamstats.usgs.gov, is a map-based web application that provides an assortment of analytical tools that are useful for water-resources planning and management, and engineering purposes. Developed by the U.S. Geological Survey (USGS), the primary purpose of StreamStats is to provide...
Ries, Kernell G.; Newson, Jeremy K.; Smith, Martyn J.; Guthrie, John D.; Steeves, Peter A.; Haluska, Tana; Kolb, Katharine R.; Thompson, Ryan F.; Santoro, Richard D.; Vraga, Hans W.
Compilation of streamflow statistics calculated from daily mean streamflow data collected during water years 1901–2015 for selected U.S. Geological Survey streamgages
Streamflow statistics are needed by decision makers for many planning, management, and design activities. The U.S. Geological Survey (USGS) StreamStats Web application provides convenient access to streamflow statistics for many streamgages by accessing the underlying StreamStatsDB database. In 2016, non-interpretive streamflow statistics were...
Granato, Gregory E.; Ries, Kernell G.; Steeves, Peter A.
Discharge measurements at gaging stations
The techniques and standards for making discharge measurements at streamflow gaging stations are described in this publication. The vertical axis rotating-element current meter, principally the Price current meter, has been traditionally used for most measurements of discharge; however, advancements in acoustic technology have led to important...
Turnipseed, D. Phil; Sauer, Vernon B.
From the River to You: USGS Real-Time Streamflow Information...from the National Streamflow Information Program
This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data,...
Nielsen, Joseph P.; Norris, J. Michael
StreamStats: A U.S. Geological Survey Web Application for Stream Information
Ries, Kernell G.; Steeves, Peter A.; Coles, Jacqueline D.; Rea, Alan H.; Stewart, David W.
The stream-gaging program of the U.S. Geological Survey
The U.S. Geological Survey stream-gaging program provides streamflow data for a variety of purposes. The uses of streamflow data are described, and the growth of the stream-gaging program is related to legislation and the need to manage the Nation's water resources more effectively. A brief description is provided of the data-collection processes...
Wahl, Kenneth L.; Thomas, Wilbert O.; Hirsch, Robert M.
The Vital Nature of Streamgaging
Gary Moore spent the last three days of 2015 stacking hefty bags of sand in front of a fellow church member’s brick home. With only 1,000 feet between the house and the swelling Mississippi and Meramec Rivers, Moore and other volunteers worked quickly, in frigid temperatures, to assemble a 10-foot high, 1,000-foot-long sandbag wall to ward off floodwaters.
Follow Your Stream to Learn About Water
Explore America's streams and rivers from your computer or mobile device.
Stay Current on Your Rivers with USGS WaterNow
For the first time, anyone can find out the current conditions on thousands of rivers and streams across the country, right from their phone, using USGS' latest system WaterNow.WaterNow makes the water conditions monitored by more than 16,000 streamgages and other sites across the country available via text or email.
Advances in Streamgaging | Reach-Scale Monitoring Experiment (1 of 2)
In this first installment of a two part series, The Arizona Water Science Center has developed new stream gaging methods that would measure flood flows remotely. However, they have to verify the accuracy of these techniques, so they designed an experiment in partnership with the USDA Southwest Watershed Research Center at the Walnut Gulch Experimental Watershed that
Reach-Scale Monitoring | Advances in Stream Gaging
The Arizona Water Science Center demonstrates new methods in Reach-Scale Monitoring to improve accuracy and measurability of high flow events. By installing pressure transducers and using LiDAR to measure topography data, hydrologists are able to simulate flows with two dimensional models which will help better calibrate stream gages. These advances have potential to aid
Streamflow Gaging Station and Measurement on San Pedro River, AZ
USGS employee, Hanna Coy, talks about stream gauging.
Streamgages: The Silent Superhero
Whether you drink water from your tap, use electricity or canoe down your local river, chances are you benefit from USGS streamgage information. So what is a streamgage and what does it do for you? This CoreCast episode gives you the inside scoop on your silent superhero.
Transcript and captions available soon.
Gaged stream reach East Brook east of Walton, NY
Gaged stream reach East Brook east of Walton, NY
