Surface and Groundwater Monitoring

Surface water can be affected by land use, agricultural practices, pollution and climate change. As you already know, monitoring and treatment of surface water requires significant investments in time and money. These investments and public health may be jeopardized if surface water changes during extreme events or contamination.

SonTek and other Xylem instruments work to provide a continuous and comprehensive record of water quantity and quality. Our instruments provide the reliable data you need to act quickly, work efficiently and reduce costs.

We understand the challenges of working in natural environments. Our systems play a key role in improving water quality and plant efficiency, while allowing for early warning and rapid response to events such as floods and algal blooms.

NEW: Evolution of Water Quality Monitoring eBook (25MB PDF)

The Evolution of Water Quality Monitoring

SonTek Products

FlowTracker2 Handheld ADV

FlowTracker2® Handheld-ADV®

Wading Discharge Measurement Instrument

What is the FlowTracker2?

The SonTek FlowTracker 2 (FT2) handheld Acoustic Doppler Velocimeter (ADV®) is a wading discharge measurement instrument that is handheld, portable and precise.

We know our users love and trust the technology with the original FlowTracker, but we wanted more! The FlowTracker2 now comes with functional, modernized features such as Bluetooth, GPS, and a large color screen, to name only a few. The enhancements came directly from the evaluation and feedback from hydrologists, researchers, and scientists who have made the FlowTracker their instrument of choice.

Portable. Precise. Practical. 

The real advantage becomes clear from the moment you start to collect data. Each step of the way FT2 guides you along the measurement process with visual prompts and SmartQC audio alerts just in case something important needs your attention. FT2 handheld software is intuitive, easy to navigate, and includes real-time plots of point data, QC parameters, and measurement verticals, giving you everything you need at-a-glance. Get defensible data correctly, the first time, every time, and minimize data handling back at the office.

Whenever, and wherever you need. 

With rugged construction for any climate and multiple display options for both day and night, FT2 goes whenever and wherever you need it to go. This includes: 

  • Natural Streams, Open Channels & Lakes
  • Irrigation Canals
  • Mining Channels
  • Water Treatment
  • Storm Water
  • Weirs / Flumes

FT2 uses SonTek’s tried-and-true ADV technology, vetted for decades by experts across the globe, in hydraulics labs, and wide-ranging field environments. Improved and perfected for FT2, the acoustic-based ADV sensor offers unparalleled accuracy, particularly in low flow, and in the shallowest water of any wading device. 2-D data in the horizontal plane (2D/3D option available) allows the most comprehensive QC and understanding of flow conditions. User calibration is never required, and 24/7 tech support from SonTek and our worldwide team is only a call away.

Still not sure if the FlowTracker2 is right for you? 

Learn more about what makes FT2 a step above the rest! Download the brochure for a complete listing of special features. Or Check out our Manual and select the technology best suited for your flow monitoring requirements! As always, we are here to help if you have questions! 

SonTek-SL Series

SonTek®-SL Series

Inspired by the need for a simple way to measure water velocity and level in open channels

Inspired by the need for a SIMPLE way to measure water velocity and level in open channels, the SonTek-SL (affectionately known as the Side-Looker or "SL") has earned worldwide acceptance as a long-term monitoring solution. Now, with two new (3G) models turbo-charged by our proprietary SmartPulseHD®, the SonTek-SL features  accessories, mounting options, software, and a variety of integration formats to ensure it fits your application.

Designed specifically for side mounting on bridges, canal walls, or riverbanks, the SL's SLEEK, low-profile housing makes installation easy.  With three models to choose from, the SL can be used in channels as small as you can jump across to rivers as wide as the Amazon. Ultra narrow beam widths combined with unmatched side lobe suppression provide the SUPERIOR acoustic directivity necessary for achieving maximum horizontal range free of interference from surface or bottom boundaries.

RiverSurveyor M9 & S5

RiverSurveyor® S5 and M9

A new perspective to the notion of measuring open channel hydraulics

NEW! rQPOD Remote Boat Surveying Package

Taken to Incredible Extremes. 

The RiverSurveyor S5/M9 is a river discharge measurement system without the traditional limitations. Small, portable, and easy to use, the patented and award-winning RiverSurveyor measures in extreme flood or drought situations within a single instrument, and without changing user settings. The results speak for themselves - the RiverSurveyor S5/M9 has revolutionized the way discharge is measured in rivers and canals. 

Multiple acoustic frequencies with SmartPulseHD® make for the most robust and continuous shallow-to-deep measurements ever and an array of four deterministic microcontrollers expertly apportion the proper acoustics, pulse scheme, and cell size allow users to focus on the measurement - not the setup. The system even has a vertical beam for accurate channel definition and it’s all designed to work intuitively. Slow to fast, shallow to deep, the RiverSurveyor S5/M9 handles it all on the fly.

Display. Process. Analyze. 

The RiverSurvery S5/M9 will exceed your expectations during and after the measurement with the RiverSurveyor Live! software suite for both PC and mobile platforms. All programs take full advantage of SmartPulseHD and the intelligent software ensures no loss of data during telemetry dropouts, with multi-language support available. Easily switch between computer or mobile devices during mid-measurement. Several quality indicators and statistics with selectable graphics provide instant feedback on data collection. 

Get More Value. 

The RiverSurveyor S5/M9 systems just keep on getting better. Our engineers continue to improve and build upon the award-winning technology, with features to include:

  • No tagline/tape measure required: With RiverSurveyor Stationary Live, automatically measure distance between stations with DGPS or RTK GPS equipped systems.
  • Manual configuration: Now you can set blanking distance, cell size and number of cells for moving boat measurements.
  • Real-time QA/QC warnings: Know when there could be a problem before there is one.
  • Zipped files: New and improved compression and auto-decompression, providing faster access to large amounts of data.
  • Sample filter: Remove your random velocity outliers with ease.

Interested in enjoying safe, remote-controlled surveying? With the rQPOD remote boat surveying package you can! The rQPOD system is sold as a complete kit from SonTek and includes a Torrent Board V7 floating platform, patent-pending motorized system. Combine this lightweight convertible platform with a RiverSurveyor-M9 or S5 to measure flow or a HydroSurveyor-M9 and measure bathymetry. This portable solution truly is ready wherever you need it! 

SonTek-IQ series

SonTek-IQ® Series

Ideal for monitoring flows in canals, culverts, pipes, and natural streams

Ideal for monitoring flows in canals, culverts, pipes, and natural streams, the SonTek-IQ starts with a custom flow algorithm derived from hundreds of field measurements. Four velocity beams profile water velocity along both the length and width of the channel, to ensure best possible coverage and most accurate representation of the velocity field. The built-in pressure sensor and vertical acoustic beam work in tandem to measure water level. Simply input the channel geometry using the intuitive SonTek-IQ software and you are outputting flow data in minutes.

All stainless steel hardware makes the IQ even more capable in difficult environments such as stormwater and certain wastewater where corrosion is a potential concern.

Other Xylem Brands



Multiparameter 6-port water quality sonde with anti-fouling wiper

The EXO advanced water quality monitoring platform includes the versatile multiparameter EXO2 sonde for oceanographic, estuarine, or surface water applications. Smart Sondes and sensors allows the user to automatically configure a sonde with different sensor for different applications in minutes.

WaterLOG Storm 3 Data Logger

WaterLOG Storm 3 Data Logger

Basic to complex communication and I/O solutions.

The Storm 3 has emerged faster, smarter and more specifically designed for today's technological advances while maintaining simplicity and ease of use. The Storm 3 is our mid-range data logger with an ideal cost-to-performance ratio. The Storm 3 incorporates a balanced set of inputs for analog, digital I/O and SDI-12 smart sensors to allow communication through cellular modems and GOES satellite. You'll love how easy it is to configure and collect data using the browser-based graphical user interface (GUI) with all standard web browsers on PCs, tablets and smart phones. You can also view your password-protected and public data anywhere with internet access using our cloud hosted data solution Storm Central.

YSI IQ SensorNet 2020 XT

YSI IQ SensorNet 2020 XT

Improve Operational Efficiency with Continuous Data

The YSI IQ SensorNet 2020 XT is a modular water quality system for a complete sensor network ideal for various installation needs. The modular system can accept additional sensors easily at any time. This is a powerful system to continuously measure water quality parameters anywhere in a facility for process control. Immediate benefits include better network visibility and management, early detection of network failures, improved compliance with regulatory targets and cost savings (energy, pump/blower maintenance, labor).

YSI Integrated Systems Bay Buoy

YSI Integrated Systems Bay Buoy

Designed for long-term water quality monitoring in surface water

The bay buoy is a medium-sized platform suitable for lakes, rivers and coastal applications.  It is designed around logging, sensors, and remote telemetry.  The bay buoy platform will deliver data for years, making it suitable for research and long-term monitoring applications.