Water Flow, Current Measurement and Velocity Data Collection

SonTek manufactures affordable, reliable Acoustic Doppler Current Profiling (ADCP) instrumentation for water velocity measurement in oceans, rivers, lakes, harbors, estuaries, and laboratories. Our instruments use sound waves to tell you how fast water is moving, where it is moving, and even if it is not. Our customers are scientists, engineers, hydrologists, research associates, water resource planners, and anyone needing to collect velocity, flow, or discharge data in every body of water imaginable.

Instantaneous Monitoring

An Instantaneous Measurement is taken out into the field for a measurement of the current velocity and/or flow conditions. Select any one of these instruments to learn more about their ideal applications and technical specifications.

rs5 rtk canal deploy

SonTek-RS5: Robust data from the world’s smallest ADCP.

riversurveyor m9 tow deploy

SonTek M9: Award-winning, multi-frequency discharge or bathymetric data collection ADCP.

FlowTracker2-ADV: Trusted handheld wading discharge Acoustic Doppler Velocimeter.

FlowTracker2-ADV: Handy and flexible option for hydraulic research projects.

Continuous Monitoring

Looking for a long-term data collection solution? Our Continuous Monitoring instruments allow for permanent to semi-permanent installations for collecting water velocity and/or flow measurements on a regular, user programable time interval.

SonTek-IQ Series: Monitor flow in canals, culverts, pipes, and natural streams.

SonTek-SL Series: Convenient side-mounted system doppler for velocity and level data.

Conductivity Temperature Depth

An industry favorite! The handheld CastAway®-CTD is a lightweight, easy-to-use instrument designed for quick and accurate conductivity, temperature, and depth profiles.

CastAway-CTD: The user-friendly, handheld, castable instrument for CTD profiles.

Featured Video

Day in the Life of a Hydrographer, with Kevin Labbe

Hydrographers, Hydrologists, Research Scientists (and more) who work to understand better water properties and distribution are paramount to ensuring the sustainability of this resource well into the future.  

Please look at a day in the life of Application Engineer Kevin Labbe. He helps researchers from the University of Georgia learn how to best use the SonTek-RS5, YSI's EXO2, and other instrumentation in the estuaries of Little St. Simons, Georgia.

Global Application Success Stories

Tiny Island, Big Insights

At just 11,000 acres, Little St. Simons Island is a tiny squiggle on most maps. But its subtle uplands—just 10 to 12 feet above sea level at best—and sprawling wetlands present a significant opportunity to study coastal dynamics. Big questions drive research on this small Georgia Island.

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HydroSurveyor Enables Rapid Indian Railways Bridge Surveys

Flood events on rivers can cause erosion of the soil around a bridge foundation, a process known as bridge scour. Over time, scour can cause dangerous foundation instability and is the leading cause of bridge failure. Acoustic technology makes railways safer.

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Researching Climate Change with CTD Monitoring Technology

A group of Arctic researchers has employed the latest monitoring technology to investigate the effects of climate change by measuring temperature and salinity in the water column beneath surface ice. The investigation results, which used SonTek’s CastAway-CTD, could illuminate our understanding of how shifting ocean currents impact the climate in northern Europe.

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Streamflow Data Improve Greenland Ice Melt Models

A multidisciplinary team of hydrologists, climate scientists, and modelers led by UCLA geographer and geologist Laurence C. Smith uses the SonTek-M9 in Greenland Ice Sheet rivers to ground-truth runoff model predictions.

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Reef Resilience: Scientist Surfer Studies Coral Reef Survival

Before Dr. Cliff Kapono shifts his research to the stage of sampling and analyzing microbiota from the reef, he characterizes the flow of water and sediment throughout the water column. His tool is a SonTek CastAway-CTD, which measures conductivity, temperature, and depth at a rate of 5 Hz and then calculates salinity, sound speed, and other parameters.

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Clever Kayak Rig Navigates Tricky Bathymetry Challenge

Bret Webb of the University of South Alabama is a master at cobbling together clever solutions in challenging situations. When he realized he couldn’t launch his instrument-laden JagSki watercraft at Lake Forest, he rigged a bathymetry-surveying kayak—the JagYak.

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Monitoring and Ingenuity Help Louisiana Communities Battle Storms

Working with the tides—especially in a half-aquatic system—requires a close eye on water flow. Delta Coast Consultants worked with Xylem to install monitoring instrument suites on both sides of its many barge gates. These stations provide data on water level, velocity, flow and direction, and wind speed and direction. These data are transmitted to the levee district's command center every six minutes.

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Science, Exploration, and the Handy CastAway-CTD

Expedition Glacialis is a global, scientific venture to monitor marine wildlife in some of the most remote places in the world.

Top Reasons You Need the SonTek-RS5

The SonTek-RS5 is a hand-sized, grab-and-go instrument and is ideal for collecting discharge data in small rivers and streams.


Comparison of Doppler Flow Meter Types: Low-Cost Continuous Wave vs Multi-Cell, Pulsed Doppler Systems

Find out why not every flow meter is created equally. Take a comprehensive look at the functional and technical differences between continuous wave vs Multi-cell pulsed Doppler technology and the advantages and disadvantages of each including:

  • Principle of operation
  • Number of beams
  • Bias potential
  • Depth requirements
  • Minimum velocity requirements
  • Flow calculation
  • Accuracy