Surface and Groundwater

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.

  • Water Quality Sampling
  • Monitoring
  • Water Flow & Level
  • Survey & Mapping/Datalogging
YSI EXO1 and handheld

YSI EXO1 Multiparameter Sonde

Capturing accurate data in fresh water, ground water and marine aquatic environments is easy with the versatile multiparameter EXO1 sonde. Ideal for estuarine, surface water or ground water applications.

SonTek CastAway CTD meter

SonTek CastAway® CTD

NEW! Now integrated with HYPACK®! [Learn more]  Designed for coastal profiling, the CastAway-CTD® incorporates a 6-electrode conductivity cell, coupled with a fast response thermistor to provide highly accurate, high resolution CTD measurements to depths of 100m.

YSI ProDSS Handheld Instrument

YSI ProDSS - Digital Sampling System

The YSI ProDSS (digital sampling system) handheld multiparameter meter provides extreme flexibility for the measurement of a variety of combinations for dissolved oxygen, turbidity, conductivity, specific conductance, salinity, resistivity, total dissolved solids (TDS), pH, ORP, pH/ORP combination, ammonium (ammonia), nitrate, chloride and temperature along with depth.

YSI Pro Plus multiparameter instrument

YSI Professional Plus Multiparameter Meter

The YSI Professional Plus handheld multiparameter meter has been discontinued and YSI is no longer accepting orders for this instrument. We recommend ProQuatro or ProDSS handheld instruments as suitable replacements.


YSI Pro30 Conductivity, Salinity Meter

The Pro30 provides everything you need in a handheld meter that measures salinity, conductivity, specific conductance, total dissolved solids, and temperature. Rugged, simple and reliable.

YSI 9500

YSI 9300 + 9500 Photometer

The YSI 9300 and YSI 9500 are economical photometers in small packages for any application. These portable photometers allow you to easily take readings directly in the field for 100+ parameters.

PRO20 Handheld DO Meter

YSI Pro20 Dissolved Oxygen Meter

The Pro20 provides everything you need in a handheld dissolved oxygen meter. Ruggedness, simplicity and reliability are the cornerstones of the instrument's design.

PAR - Photosynthetically Active Radiation

YSI PAR System - Photosynthetically Active Radiation

YSI offers several PAR systems that can be directly integrated into existing or new 6600 multiparameter sondes. PAR sensors are powered by the sonde and PAR data is added to the data stream of the water quality sonde.

YSI  Pro10 pH (or ORP)

YSI Pro10 pH / ORP Meter

The Pro10 provides everything you need in a handheld meter that measures temperature along with either pH or ORP (redox). Rugged, simple and reliable. Measure pH or ORP, and temperature.

Pro1020 Handheld DO pH Meter

YSI Pro1020

The Pro1020 provides everything you need in a handheld meter that measures dissolved oxygen and temperature along with either pH or ORP (redox). Rugged, simple and reliable. Measure pH or ORP, dissolved oxygen, and temperature.

handheld pH/Conductivity or ORP/Conductivity Meter

YSI Pro1030

The Pro1030 provides everything you need in a handheld meter that measures pH or ORP (redox) along with conductivity. Rugged, simple and reliable. Measure pH or ORP, salinity, conductivity, specific conductance, TDS, and temperature.

Pro2030 Handheld DO/Conductivity Meter

YSI Pro2030

The ideal replacement for the discontinued YSI Model 85. The Pro2030 provides everything you need in a handheld dissolved oxygen meter that automatically compensates for changes in salinity values. Rugged, simple and reliable. Measure DO, salinity, conductivity, specific conductance, TDS, barometric pressure and temperature.

EcoSense ODO200 Handheld

YSI EcoSense ODO200 Handheld - Optical Dissolved Oxygen Meter

Accurate, economical, handheld dissolved oxygen measurements using optical technology.

The EcoSense® line of compact, handheld instruments provides the most accurate data in the most affordable format. The instruments feature an easy-to-use interface, one-hand operation, IP67 waterproof case, and low cost of ownership over the life of the product.

YSI EcoSense DO200A Dissolved Oxygen Meter Kit

The DO200A is part of the EcoSense® family of products. The DO200A dissolved oxygen instrument offers fast dissolved oxygen response times in wastewater, surface water, and aquaculture applications.

YSI pH100A

YSI EcoSense pH100A Meter Kit

YSI's EcoSense® product line of compact, handheld instruments includes the pH100A pH meter. For simple, one handed operation for pH readings or mV values and temperature the pH100A is a logical choice.

YSI EXO1 and handheld

YSI EXO1 Multiparameter Sonde

Capturing accurate data in fresh water, ground water and marine aquatic environments is easy with the versatile multiparameter EXO1 sonde. Ideal for estuarine, surface water or ground water applications.

YSI EXO2 multiparamter water quality instrument

YSI EXO2 Multiparameter Sonde

The EXO advanced water quality monitoring platform includes the versatile multiparameter EXO2 sonde for oceanographic, estuarine, or surface water applications. Collect data to 250m with the advanced EXO2 sonde – contains six replaceable 'smart' sensors and a central wiper to clean biofouling.

Aanderaa Aqua Optode 4531

Aanderaa Oxygen Sensor

The Aanderaa Oxygen Sensor was the first and only to measure dissolved oxygen for years without drift. Now it is one of the fastest!

Aanderaa Oxygen Sensor is designed to measure absolute oxygen concentration and % saturation. The oxygen optode can be used from streams to deep sea, from Aquaculture to Waste water and from Polar ice areas to Hydrothermal vents. The lifetime-based luminescence quenching principle offers the following benefits:

Buoy - Vertical Profiling System

YSI 6952 Buoy - Vertical Profiling System

The YSI 6952 Buoy - Vertical Profiling System offers user-programmable sample intervals, redundant error recovery logic that detects unexpected activity and recovers automatically, and is compatible with all YSI EXO and 6-Series sondes equipped with depth.

MJK pHix Compact

MJK pHix Compact


The unique design of pHix Compact eliminates high impedance electrode connections and use of special hardware for mounting, and with the large surface of the pHix Compact reference junction the electrode is less sensitive to pollution.

All known issues such as corrosion, moisture and oxidation due to high impedance are practically eliminated with this construction.

This is one of the most user friendly pH transmitters on the market. The buffer adjustment of the pHix Compact is very easy to perform securing high repeatability.

M9 S5 Multi-Frequency ADCP

SonTek RiverSurveyor® S5 and M9

The patented and award-winning RiverSurveyor®, S5/M9 systems give a new perspective to the notion of measuring open channel hydraulics. Using SonTek's exclusive SmartPulseHD®, multiple acoustic frequencies are fused with precise bandwidth control for the most robust and continuous shallow-to-deep discharge measurements ever.

SonTek FlowTracker2

SonTek FlowTracker2® Handheld-ADV®

The new FlowTracker2 (FT2) handheld Acoustic Doppler Velocimeter (ADV®) has all the technology you have grown to know and trust with the original FlowTracker, but now comes with functional, modernized features (Bluetooth, GPS and large color screen, to name only a few) based on the evaluation and feedback from hydrologists, researchers and scientists who have made the FlowTracker their instrument of choice.

Magflux Flow meter

MJK MagFlux® Flowmeters

MagFlux® Flowmeters are developed for measurements in all types of conductive liquids, including measurement of flow in drinking water, wastewater, sludge and process water. MagFlux Flowmeters are manufactured with carbon steel and stainless steel for flange or wafer connections and lining in hard or soft rubber and PTFE/PFA.

SonTek-IQ® Series

SonTek-IQ® Series

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 in 3-D - both vertically and horizontally - ensuring complete coverage 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.

SonTek®-SL Series

SonTek®-SL Series

NEW SL1500/3000 3G MODELS! The SonTek-SL has two new (3G) models turbo-charged by our proprietary SmartPulseHD®, the featured accessories, mounting options, software, and a variety of integration formats ensure it fits your application.

Shuttle® Ultrasonic Level Transmitter

MJK Shuttle® Ultrasonic Level Transmitter

With MJK cabled sensors, it is easy to position the transmitter with the display, where it can be useful, and the large display allows viewing from a distance. Tne one-step measurement start-up procedure is easy to follow and easy to modify the set-up of all functions, controls and signal management features. 

MJK Expert™ 367

MJK Expert™ Hydrostatic Level Series

MJK offers a full series of water level transmitters designed for immersion in open tanks, wet-wells, ground water and reservoirs. The water level transmitters are designed for measurement under rough conditions in all water and wastewater applications with large concentrations of sludge and suspended solids.

YSI Amazon Bubbler

YSI Amazon Water Level Bubbler

Designed with simplicity in mind, the Amazon bubbler is the ideal system for long-term, water level monitoring sites. It can be used as a stand-alone system with internal data storage, or as a sensor connected to any manufacturers data logger. Easily configure and collect data using the browser-based graphical user interface with all standard web browsers on PCs, tablets and smart phones. It's rugged build, and technologically advanced system makes the Amazon Bubbler an attractive solution for real-time monitoring and data collection.

MJK 713 Flow Converter

MJK 713 Open Channel Flowmeter

MJK 713 Open Channel Flow Measurement and Regiatration of water Flow is a converter adaptable to many types of weirs and open channels.

The built-in ISO 1438 formulas for flow calculations are preprogrammed with the most common flumes and weirs such as Parshall, Venturi, Palmer-Bowles flumes and V-notch and rectangular weirs. Also to be used with non-standard channels and weirs, often installed at waste water plants and stormflow locations.

713 Open Channel Flowmeter is primarily used for measuring flow outlet from waste water treatment plants. The flow is calculated upon the water level, provided by either ultrasonic or hydrostatic level transmitter.

Built-in ISO 1438 formulas will provide the most common formulas, but it is possible to calculate flow from simple formula and level/flow linearization as well.

Built-in totalizer with non-resettable counter, and short term flow overview.

Easy to use and setup due to symbolic navigation buttons and multiple display languages.

SonTek HydroSurveyor

SonTek HydroSurveyor™

NEW! Now integrated with HYPACK®! [Learn more]  The HydroSurveyorTM is a system designed to collect bathymetric, water column velocity profile, and acoustic bottom tracking data as part of a hydrographic survey. The two key components of the system are the HydroSurveyor Acoustic Doppler Profiler (ADP®) platform, and the powerful, yet user-friendly, data collection software.


Aanderaa SmartGuard Datalogger

SmartGuard is the next generation sensor and instrument HUB for Ocean, Lake, Reservoir, Estuary and River Hydrometric stations. It's a complete observatory node for advanced Hydrologic/Meteorological stations as well as for small stand alone stations.

Storm 3 Datalogger

YSI WaterLOG Storm 3 Datalogger

The Storm 3 Data Logger 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.

MJK chatter-lock

MJK Chatter Datalogger

Logging data far away from urban areas is handled by a battery powered datalogger, that gather information and send the information to a SCADA system, dedicated databases or even as e-mails when its suitable to do so.

Publicly placed dataloggers are vandal protected, and will send a warning when intruders act.

Sending data once a day will provide at battery life time of up to 5 years.

Information on ground water levels and early warning sewer systems in correlation with buildings nearby urban construction can save millions of Euros in damage.