Designed for in situ monitoring and profiling, and ideal for long-term deployments requiring the most complete water quality data record.

The YSI Castaway is the worlds first CTD to provide instantaneous profiles for temperature, conductivity, salinity, depth and speed down to 100m.

The RiverSurveyor M9 and S5 are the next generation of acoustic doppler for measuring open channel flow. Using SonTek’s exclusive multiple acoustic frequencies allows continuous shallow-to-deep discharge measurements. A range of new technologies means you can focus on the measurement, not the instrument setup. In addition to this the system has a vertical beam for precise channel definition and it's all designed to work intuitively

The Cable Chimp II is a great choice when choosing a remotely-operated cableway vechicle. High data-quality stream gauging requires slow, even and repeatable towing, making the Cable Chimp II the best and most reliable way to consistently collect high data-quality from small tethered boats

Remote boat

The Flowtracker has been designed with the field user in mind, this handheld Acoustic Doppler Velocimeter (ADV) measures 2D or 3D currents, attaches easily to wading rods, and features an automatic discharge computation using a variety of international methods, including ISO and USGS standards. At the end of the data run, just press a button and the FlowTracker calculates the discharge for you!

Designed with the need for an easy way to measure water velocity, level and calculate flow / discharge in open channels, the Argonaut-SL has earned worldwide acceptance as a long-term monitoring solution. Fully featured with accessories, mounting options, software, and a variety of integration formats, the Argonaut-SL fits your application in the way you need it to.

The new ProODO^™ offers traditional YSI quality with the latest luminescent optical dissolved oxygen  technology. The ProODO utilises a proven digital sensor technology to offer the most accurate dissolved oxygen data from a portable field meter.

The YSI Professional Plus is a universal handheld multiparameter meter providing extreme flexibility for the measurement of a variety of combinations for dissolved oxygen, conductivity, specific conductance, salinity, resistivity, total dissolved solids (TDS), pH, ORP, pH/ORP combination, ammonium (ammonia), nitrate, chloride and temperature. Also a very powerful lab instrument for BODs, pH and ORP.

Leading handheld water quality meter in the UK certified with MCERTS the YSI Professional Plus Quatro is a field rugged meter capable of measuring temperature, conductivity, salinity, pH and dissolved oxygen plus one of redox, ammonium, nitrate or chloride. Applications include surface and groundwater monitoring.

The EcoMapper is a unique AUV (autonomous underwater vehicle) designed to create high-resolution maps of water quality and bathymetry.

PeliNet is a portable, instantly deployable, telemetry solution for short term and emergency monitoring applications. PeliNet is based on YSI's Econet system allowing the user to make instant, meaningful decisions without the need for additional costly resources or time-consuming trips to the field.

The SonTek Argonaut SW (shallow water) is designed to measure flows in small channels from 0.3 m to 5 m deep. Using advanced pulsed Doppler technology the Argonaut SW can be used on sites previously thought impossible to measure. This bottom mounted device measures water level and vertically-integrated velocity making it ideal for sites with reversing or stratified flow conditions

The EMM700 buoy is a medium-sized platform suitable for near-shore and inland water 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.

The YSI 650 is a field rugged display / datalogger capable of communicating with any YSI 6-Series multiparameter instrument

Its now possible to expand your water quality monitoring to include hydrocarbons or oil with the YSI Sensor Adapter. The YSI Sensor Adapter expands water quality monitoring to include third-party analog output sensors allowing the 6 Series sondes to measure hydrocarbons and other parameters.