Measuring water velocity is essential in river gauging, hydrological studies, environmental monitoring, coastal research and many other field applications. But the right instrument depends heavily on where the measurement is being taken, the depth of the water, the expected current velocity and whether information such as flow direction or depth is also required.
A shallow stream that can be accessed by an operator does not necessarily require the same instrument as a deep river, lake or estuary. EMCON therefore offers different current-meter configurations for different measurement conditions, including Wading Rod Current Meters, Suspension Type Current Meters and Water Current Meters with Direction Measurement.
Understanding the differences between these systems makes it easier to select an instrument that suits the actual field requirement.
Why the Measurement Environment Matters
The first step in choosing a water current meter is understanding the measurement location.
In shallow streams, canals or smaller rivers, an operator may be able to physically position a sensor at the required measurement point. In deeper water bodies, however, the sensor may need to be suspended from the surface using a cable and lowering system.
Estuarine and coastal studies introduce another requirement: knowing the direction of the current may be just as important as knowing its velocity.
The choice should therefore be based on the measurement objective rather than simply selecting a current meter based on maximum range.
1. Wading Rod Type Current Meter
A Wading Rod Current Meter is particularly suited to accessible water bodies where the sensor can be positioned directly at the required observation point.
EMCON’s Savonius Rotor Type Current Sensor is designed for measurements in small creeks, rivers, canals and other water bodies. It provides direct water-current readings through a portable handheld LCD display. The specified velocity range is 0 to 4 m/s, with an accuracy of 0.03 m/s and a sensing threshold below 0.02 m/s. EMCON-Wading Rod Type Water Cur…
The instrument uses a Savonius rotor and reed-switch sensing method designed to detect currents at relatively low velocities. The standard cable length is 2.5 metres, with longer cables available where required. EMCON-Wading Rod Type Water Cur…
This makes the wading-rod configuration particularly practical when measurements are being taken in relatively shallow and physically accessible locations.
2. Suspension Type Water Current Meter
When measurements need to be taken in deeper rivers, lakes or estuaries, a Suspension Type Water Current Meter becomes more appropriate.
EMCON’s suspension-type system measures both water-current velocity and depth and provides direct readings through a handheld LCD/OLED display. Its water-current range is 0 to 5 m/s, with a stated accuracy of ±0.02 m/s and a sensing threshold below 0.04 m/s. EMCON- Suspension Type Water Cu…
The integrated depth sensor has a standard range of 0 to 20 metres, with other ranges available on request, and an accuracy of ±1% of full scale. The system includes a 22-metre cable and nylon handling rope and is designed for measurements in rivers, lakes, estuaries and other water bodies. EMCON- Suspension Type Water Cu…
An important feature described in the product documentation is underwater stabilisation intended to reduce errors caused when water thrust tilts the suspension cable at higher velocities. EMCON- Suspension Type Water Cu…
For surveys where the operator cannot physically enter the water or where measurements are required at different depths, this type of system provides a more suitable configuration.
3. Water Current Meter with Direction
Some studies require more than velocity alone. In rivers, estuaries and ocean environments, researchers may also need to understand where the water is moving.
EMCON’s Water Current Meter with Direction combines velocity and directional measurement in one portable system. The handheld unit displays both parameters directly on an LCD display.
The velocity sensor has a range of 0 to 5 m/s, accuracy of ±0.02 m/s and a threshold below 0.01 m/s. The instrument uses a Savonius rotor for low-range current sensing. Emcon MODE STUDIES Brochure 16 …
Direction is measured using an electromagnetic miniature direction sensor covering 0° to 360°, with a stated accuracy of ±4°. The system uses a 20-metre cable and stainless-steel construction intended for marine use. Emcon MODE STUDIES Brochure 16 …
The meter also measures average water velocity over a fixed period, which can support more representative observations where the current fluctuates rather than remaining constant. Emcon MODE STUDIES Brochure 16 …
Comparing the Three Options
| Requirement | Wading Rod Current Meter | Suspension Type Current Meter | Current Meter with Direction |
|---|---|---|---|
| Typical environment | Small creeks, rivers, canals | Rivers, lakes, estuaries | Rivers, oceans, estuaries |
| Velocity range | 0–4 m/s | 0–5 m/s | 0–5 m/s |
| Velocity accuracy | 0.03 m/s | ±0.02 m/s | ±0.02 m/s |
| Low-velocity threshold | <0.02 m/s | <0.04 m/s | <0.01 m/s |
| Depth measurement | No integrated depth measurement specified | Yes, 0–20 m standard | No integrated depth measurement specified |
| Direction measurement | No | No | Yes, 0–360° |
| Display | Handheld LCD | Handheld LCD/OLED | Handheld LCD |
| Standard cable | 2.5 m | 22 m | 20 m |
| Best suited when | Water is accessible and relatively shallow | Measurements are required at depth | Both velocity and direction are required |
Specifications are based on the respective EMCON product documents. EMCON-Wading Rod Type Water Cur… EMCON- Suspension Type Water Cu… Emcon MODE STUDIES Brochure 16 …
How to Select the Right Current Meter
A practical selection process can be based on five questions:
- Can the measurement point be accessed directly? For shallow, accessible waterways such as creeks and canals, a wading-rod system can provide a straightforward portable solution. For deeper locations, a suspension-type system is more appropriate.
- Do you also need to measure depth? If velocity and depth need to be observed from the same system, the Suspension Type Water Current Meter provides an integrated depth sensor alongside current measurement. EMCON- Suspension Type Water Cu…
- Is current direction important to the study? For estuarine, oceanographic or other studies where flow direction matters, use a system specifically equipped with directional sensing rather than attempting to derive direction from a velocity-only meter.
- What velocity range do you expect? The expected current should fall comfortably within the instrument’s specified range. Low-flow studies should also consider the sensing threshold, particularly where detecting relatively small water movements is important.
- How will the instrument be deployed? Consider cable length, sensor handling, portability and the physical environment. For example, EMCON’s directional current meter uses stainless-steel construction for marine use, while the suspension system is supplied with a handling rope and transport case for field operation. Emcon MODE STUDIES Brochure 16 … EMCON- Suspension Type Water Cu…
Don’t Look at Maximum Range Alone
A common mistake when selecting a current meter is to focus only on the maximum measurable velocity.
In practice, threshold sensitivity, accuracy, deployment depth, current direction, display method and physical access to the site can be equally important.
For example, two instruments may both measure currents up to 5 m/s, but one may be designed to provide depth measurements while another provides current direction. They therefore serve different research objectives despite having similar velocity ranges.
The measurement question should come first: What exactly needs to be measured, and under what field conditions?
Direct Reading Can Simplify Field Measurement
All three EMCON configurations discussed here provide direct electronic readings rather than requiring the operator to interpret a chart manually.
The wading-rod meter uses a handheld LCD unit, while the suspension system provides velocity and depth readings through a single LCD/OLED display. The directional meter displays current velocity and direction through its portable handheld unit. EMCON-Wading Rod Type Water Cur… EMCON- Suspension Type Water Cu… Emcon MODE STUDIES Brochure 16 …
For field teams, this can make measurements easier to observe and record directly at the site.
Choosing for Rivers, Lakes and Estuaries
For small creeks, canals and shallow accessible rivers, the Wading Rod Current Meter offers a compact solution for direct velocity measurement.
For deeper rivers, lakes and estuaries, particularly where measurement depth is also important, the Suspension Type Water Current Meter provides velocity and depth within the same system.
For estuaries, ocean environments and studies where flow direction must be understood, a Water Current Meter with Direction provides both velocity and directional information.
There is therefore no single current meter that is automatically the right choice for every water body. The correct instrument is the one that matches the measurement parameters, water depth, expected flow conditions and deployment method of the study.
