How to Measure Water Current of Stony Tunguska River?

1. Where is Stony Tunguska River?

The Stony Tunguska River is in Siberia, Russia. It is a major and big tributary of the Yenisei River. Its source is in the Central Siberian Plateau.

It winds its way through spacious open spaces-uninhabited by people. It represents an area, mostly of taiga forests, which are dominated by coniferous trees, spruce, and pine. On its coasts, rich and various wildlife can be found: reindeer, wolves, and many birds have their habitats in this inhospitable but breathtaking landscape. Small indigenous villages line the course of the river. These are traditional communities that strictly depend on the river for fishing and transport.

The flow in the Stony Tunguska River has a fundamental function in the given area from an ecological viewpoint. Due to its sedimentation at times of flooding or high water, the river specifically affects soil and flora in the area it flows through. The river is also part of the general water regime within Siberia, with its tributaries feeding the flow into the Yenisei River and the general hydrological cycle of the region.

2. What does the Discharge of the Stony Tunguska River look like?

The flow rate of the Stony Tunguska River is highly variable depending on the season. In spring, with snow melting, the river starts to show a remarkable rise in flow. Indeed, enormous snowfalls throughout the very long Siberian winter fall and rush into the river, creating an impressive surge in the volume of water. During this peak period, the average flow rate can reach several thousand cubic meters per second.

It has very little flow during winter. Parts of the river may completely freeze and allow only a small quantity of water to be channeled beneath the ice cover. Similarly, the occurrence of the ice cover propels the flow characteristics of the river. During spring if the ice melts, it might lead to instantaneous changes in the water level and flow velocity of the river.

The ecological balance is based on the flow of the River Stony Tunguska. It feeds huge taiga forests and means much for the survival of many aquatic and terrestrial species.

3. How to Measure Water Current of Stony Tunguska River?

There are several ways-measuring using traditional and modern methods-of finding the water current of the Stony Tunguska River. Conventional methods involve the use of floats. By dropping a float into the river and observing how it moves over a distance and time, an estimation of the surface current speed can be done. The second conventional method is the use of mechanical current meters. They are installed at chosen points in the water to measure the velocity directly.

However, the sophisticated and effective technique for discharge measurement includes Acoustic Doppler Current Profiler(ADCP). They are able to provide a more complete current profile of the river.

3.1 Principles of Operation-How Do ADCPs Using the Doppler Principle Work?

ADCP current meter work on the principle of the Doppler effect: they shoot acoustic pulses out into the water. Whenever those pulses encounter the moving particles of water, due to the Doppler effect, the frequency of the pulses reflected back changes. From this shift in frequency, the ADCP doppler is able to compute the velocity of the water at each depth.

The ADCP current profiler ​has more than one transducer, transmitting acoustic signals in different directions, and thereby it can measure water flow both horizontally and vertically. This allows the three-dimensional mapping of the water current, which is invaluable for understanding complex flow patterns of the Stony Tunguska River.

3.2 What Is Required for Quality Measurement of Currents in the Stony Tunguska River?

Considering ADCP flow meter for high measurement of currents of the Stony Tunguska River, there are many dependants on the characteristic of equipment. First of all, the case of ADCP profiler needs to be made from reliable material. The best option will be a titanium alloy.

The advantages of the Titanium alloy are manifold. Lightweight, it will be very easy to manipulate and set up the ADCP meter at its usually remotely and difficult locations of the Stony Tunguska River. Further, it enjoys excellent corrosion resistance. The cold climate and chemical constitution of water in the Stony Tunguska River automatically guarantee that accuracy and reliability remain for a long duration.

Besides that, for extensive measurement in Stony Tunguska River, it is desirable if an ADCP with low power consumption and low cost is used. It can work longer with low power-consumable ADCP and therefore it will be suitable for continuous monitoring. A cost-effective ADCP can be spread without incurring high financial costs.

3.3 How to Choose the Right Equipment for Current Measurement?

Application is the most deciding factor in choosing an appropriate ADCP for the measurement of the current of the Stony Tunguska River. If the horizontal flow across a section of the river is to be covered, then an HADCP should be used. The Horizontal Acoustic Doppler Current Profilers are meant to give proper results for the horizontal velocity components of the water current.

A VADCP will be more appropriate for vertical flow profile measurements. VADCPs are configured to measure the velocity of the water at different depths along a vertical line in the river.

Regarding frequency, 600 kHz ADCP works for water depths up to approximately 70 m for the shallower parts of the Stony Tunguska River. At deeper parts, 300 kHz works better for reliable measurement, which is up to about 110 meters.

There are well - known ADCP brands such as Teledyne RDI, Nortek, and Sontek. However, for a cost - effective option with good quality, China Sonar ​PandaADCP is worth considering. It is made of all - titanium alloy material and offers an excellent cost - performance ratio. You can find more information on their website: ​https://china-sonar.com/.

Here is a table with some well known ADCP instrument brands and models.