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Surface Water

Measuring water quantity and quality in surface water (open channels, rivers, reservoirs, lakes, and estuaries) is one of the foundations of hydrological monitoring and has been a focus of OTT Hydromet since its first  water current meters were designed in 1875.

OTT Hydromet provides versatile technology options for measurement of water level, flow/discharge, and water quality in surface water applications:

  • OTT surface water level sensors featuring a variety of measurement technologies (radar, bubbler, pressure) to meet many application needs
  • OTT current meters to measure surface water flow and discharge, with options for in-stream portable measurement or fixed installations
  • Hydrolab mulitparameter sondes for measurement of water quality either in spot sampling or unattended in real-time
  • Sea-Bird Coastal instruments for unattended nutrient water quality measurement
Acoustic Digital Current Meter

Legacy product - OTT ADC

Handheld, acoustic water flow, velocity meter for in-stream point velocity measurements

The OTT Acoustic Digital Current meter (ADC) delivers consistently accurate results with the most advanced acoustic technology available for point velocity measurement.

  • Spot
  • Acoustic
  • Flow velocity, depth
  • Latest state of the art ultrasonic Doppler technology for high accurate velocity measurements. Maintenance free sensor with integrated depth measurement, graphical step by step user guidance and discharge calculation according to ISO 748 and USGS standard
  • -0.2 … 2.4 m/s
  • ± 1% of measured value ± 0.25 cm/s
Groundwater level sensor and data logger

OTT ecoLog 500 Water Level Logger

Water level sensor with built-in datalogger for surface and groundwater applications

The OTT ecoLOG 500 is a self-contained water level instrument offering flexible remote data options and unequaled performance for the price.

  • Surface water Groundwater
  • Vented pressure cell
  • Waterlevel/Pressure, Water temperature
  • Measures, stores, and transmits water level and temperature data
  • ± 0.05% FS
  • Yes
Integrated pressure level transducer and datalogger

OTT Orpheus Mini Water Level Logger

Pressure level transducer with datalogger for longterm groundwater monitoring

The OTT Orpheus Mini is an integrated pressure sensor and datalogger for level measurement in surface and groundwater applications.

  • Surface water Groundwater
  • Vented pressure cell
  • Waterlevel/Pressure, Water temperature
  • Measures and stores water level and temperature data
  • 0 … 4, 10, 20, 40, and 100 m
  • ± 0.05% FS
  • Yes
With integrated sensor and datalogger for longterm monitoring

OTT CTD Sensor

Pressure sensor for longterm measurement of conductivity, temperature and water level

The OTT CTD is an integrated sensor and datalogger for measurement of water level, temperature, and conductivity in groundwater and surface water applications.

  • Surface water Groundwater
  • Vented pressure cell and 4-electrode graphite conductivity cell
  • Waterlevel, Temperature, Conductivity
  • Measures and stores water level, temperature, and conductivity data
  • Water level: 0 … 4, 10, 20, 40, and 100 m Conductivity: 0.001…2.000 mS/cm, 0.10…100.00 mS/cm
  • ±0,05 % FS
  • Yes
Non-contact bubbler in water level sensor for surface water monitoring

OTT CBS - Compact Bubbler Sensor

Non-contact, bubbler sensor for longterm surface water level monitoring

The OTT CBS is a compact, accurate, and low power bubbler sensor for surface or groundwater level monitoring.

  • Surface water Groundwater
  • Bubbler-in
  • Drift-free water level measurement - no pressure sensor or electronics in the water
  • 0 to 15 m or 0 to 30 m
  • ± 3 mm (high accuracy version); ± 5 mm (standard and 30 meter versions)
  • No
  • SDI-12, RS-485 (using SDI-12), or 4 ...20 mA
Contact gauge OTT KL010

OTT Contact Gauges

OTT Contact Gauges for measurements of depth to water, temperature and conductivity

OTT Contact Gauges are essential for manual water level measurements in groundwater. For measuring depth to water, temperature, and conductivity – depending on the variant.

  • Measuring tape lengths KL010: 15 ... 750 m; KL010 TM: 25 ... 500 m; KL010 TCM 30 ... 500 m
  • Groundwater
  • Contact gauge
  • Water level / Distance to water, Temperature, Conductivity
  • Manual water level, temperature and/or conductivity measurement
New water quality sonde platform: ease of use, meta-data, reliability

Hydrolab HL4 Multiparameter Sonde

New Hydrolab Platform: Reliability, Ease-of-use, Metadata

The Hydrolab HL4 is the next generation multiparameter water quality sonde from OTT Hydromet. Its reliability, ease-of-use, and metadata produce water quality data you can trust.

  • Attended Unattended
  • Temperature, Conductivity, Depth, pH, Dissolved Oxygen (LDO), Turbidity, ORP, Clorophyll a, Blue-green algae, Rhodamine, Ammonium, Nitrate, Chloride
  • The next generation multiparameter water quality instrument
  • SDI-12, RS-485, RS-232, TTY, USB
Sea-Bird Scientific Suna

Sea-Bird Scientific SUNA Optical Nitrate Sensor

High accuracy in-situ nitrate measurement

The Sea-Bird Scientific SUNA V2 UV nitrate sensor with technology by Satlantic is the ultimate chemical-free solution for autonomous monitoring in estuarine and freshwater environments.

  • Attended Unattended
  • Nitrate
  • High-accuracy, chemical-free, in-situ nitrate measurement
  • SDI-12, RS-232
superior long-term monitoring water quality SBC WQM

Sea-Bird Scientific WQM

Water Quality Monitor for Maximum Deployment Times

The Sea-Bird Scientific WQM X with technology by Sea-Bird Electronics and WET Labs is designed specifically for long-term moored operations in biologically rich water.

  • Unattended
  • Conductivity, pressure, chlorophyll, temperature, dissolved oxygen, turbidity
  • Designed specifically for extended deployment in biologically rich waters
  • RS-232
Seabird Scientific HydroCat water quality

Sea-Bird Scientific HydroCAT

For longterm water quality monitoring with proven anti-fouling technology

The Sea-Bird Scientific HydroCAT with technology by Sea-Bird Electronics (SBE) is ideally suited for extended deployments in remote, biologically rich environments.

  • Unattended
  • Temperature, Pressure, Dissolved Oxygen, Conductivity
  • Ideally suited for extended deployments in remote, biologically rich environments
  • SDI-12, RS-232, RS-485 (optional)
water level radar sensor for surface water applications

OTT RLS - Radar Level Sensor

Non-contact water level sensor for long term surface water measurements

The OTT RLS is a non-contact radar level sensor with pulse radar technology that is ideal for monitoring in remote or hard to reach locations.

  • Surface water
  • Water level / distance to water
  • Non-contact pulse radar
  • Measures water level or depth to water from a bridge, pier or mounting arm
  • 0.4 … 35 m
  • 0.8 … 2 m: ± 10 mm; 2 … 30 m: ± 3 mm; 30 … 35 m: ± 10 mm
  • No
  • SDI-12, RS-485 (using SDI-12), or 4 ...20 mA
Surface Water Velocity Radar Sensor for Discharge Systems


Surface Velocity Radar for Measuring Open Channel Flow

OTT SVR 100 is a simple, non-contact, compact surface water velocity radar sensor. Designed for measuring flow in open channels and rivers where reliable velocity data is required continuously, during floods or periods of high concentrations of suspended sediments.

  • Fixed installation
  • Identify data influenced by sensor movement (e.g., wind, traffic) using meta data from integrated vibration and tilt sensors
  • Non-contact surface velocity radar
  • No
  • 0.08 ... 15 m/s (0.26 … 49 ft./s)
Handheld electromagnetic stream flow meter with automatic discharge calculation

OTT MF pro - Water Flow Meter

Handheld electromagnetic water flow meter with automatic discharge calculation

The OTT MF Pro is a user-friendly, low maintenance electromagnetic current meter for cost-efficient in-stream discharge measurement.

  • Spot
  • Electro-magnetic
  • Flow velocity and water depth
  • Low maintenance magnetic - inductive probe with level measurement for reliable flow measurements. Works well in low flow and turbulent conditions, cross - sections with weed growth and pollution. Applicable in streams and conduits.
  • 0 … 6 m/s
  • ± 2% of measured value ± 0.015 m/s ( 0 … 3 m/s ) and ± 4% of measured value ± 0.015 m/s ( 3 … 5 m/s )
Water Quality Solutions Overview Video
OTT RLS Overview Video
Surface Water Level Sensor Guide
Hydrolab HL4 Overview Video
Hydrolab HL4 Overview Video
OTT MF pro Video - EN
OTT ADC Video - EN
Video - Adcon Smart Wireless Systems - EN
Whitepaper: Turbidity measurements
Turbidity Whitepaper
Whitepaper: QA QC (Quality assurance and control) in hydrometry
Whitepaper: OTT MF pro
Whitepaper - OTT SVR 100: Surface Velocity Radar for Measuring Open Channel Flow
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