ADCP's Application in Flood Management of Ural River

1. Where is Ural River?

The Ural River is a vital geographical feature marking the natural boundary between Europe and Asia. Originating in the southern Ural Mountains of Russia, the course of the river takes place in a generally southward direction. The river flows across all kinds of varied terrains, first mountainous at or near its source, followed by plains and semi-arid areas as it finally approaches the Caspian Sea.

It passes through the cities of Orenburg in Russia and Atyrau in Kazakhstan. In all these cities, the Ural River is vital for water supply, transportation, and industry. The climate in the Ural basin is continental-harsh with cold winters and relatively warm summers. Annual precipitation is not very plentiful, but snowmelt during spring plays a significant role in the volume of water in the river. In addition, rainfall during the summer months can also affect the river's flow.

2. What are the Reasons for Floods in Ural River?

Snowmelt: The Ural River's headwaters are in the Ural Mountains, where heavy snow accumulates during winter. As spring arrives and temperatures rise, the snow begins to melt rapidly. This can be overwhelming for a river, and its capacity meets an increase in the levels of water, probably ending up in floods. If the rate of snow melting is abnormally higher-for instance, when there is a sudden raise in temperature-the river is not able to cope with this sudden volume of water.

Heavy Rainfall: While this region does not experience extremely high rainfall, heavy rainstorms during the wet season can cause flooding. "When a heavy rain falls in a short period of time into a soil already saturated by previous rainfall or rapid snowmelt, the additional water runs off into the river very quickly. If the river is already running at close to its carrying capacity, this surge of water may be enough to push it over its banks.".

Relief and Channel Conditions: The flat plains across which a large part of the Ural River flows may be able to slow the velocity of the water. This can cause water to overflow more easily during high-flow periods. Long-term deposition within the river also reduces its cross-sectional area and conveyance capacity. Human-made changes to the river channel include the construction of dams, levees, or other structures that also can alter the river's natural flow and increase the possibility of flooding.

In this aspect, the utilization of ADCP profiler-which stands for Acoustic Doppler Current Profiler-offers a more sophisticated and effective way to monitor and manage the flow of the river and the risk of flooding.

3. How Do ADCPs Using the Doppler Principle Work?

The ADCPs rely on the Doppler principle. They send acoustic signals into the Ural River's water. Where this acoustic wave intersects with the moving particles in the water-sediment, small aquatic organisms, or other debris carried by the water flow-the frequency of the reflected waves changes compared to the originally emitted waves. This change in frequency, called the Doppler shift, is directly related to the velocity of the moving particles and, by extension, the velocity of the water flow.

The ADCPs will be able to detect the flow velocities of the water at different locations and depths inside the water column by utilizing a number of acoustic beams transmitted in various directions and receiving the reflected signals back. They can generate a very informative velocity profile of water flow using advanced signal-processing algorithms. Such information is highly important for the understanding of the hydrodynamic characteristics of the Ural River.

4. What are the Applications of ADCP in Floods of Ural River?

Velocity Measurement: The ADCP current meter will be able to measure the actual velocity of the water flow in different parts of the Ural River during the flood. This information is important for estimating the floodwater erosive force. For instance, high-velocity flows along riverbanks may show locations where erosion is likely to occur, thus enabling the implementation of precautionary measures like bank reinforcement or the installation of erosion-control structures.

Flow Measurement Application: With the integration of the velocity measurement over the cross-sectional area of the river, the ADCP flow meter can measure flow. Flow rate will definitely be needed in managing flooding, as it would allow one to project the amount of water passing through a certain section of the river. This information will show the decision-makers about decisions to be made regarding the flood-control structures like dams and levees.

Sediment Transport Research: The Ural River carries a lot of sediment. ADCP current profiler is useful in the study of the movement of sediment due to floods. By correlating the water flow velocity with sediment concentration and its movement characteristics, one can get an understanding of how floods influence the balance of sediment processes in a river and its ecological consequences.

5. How the Data Measured by ADCP can be used in flood warning and risk management for the Ural River?

Flood Warning

Monitoring of Velocity and Flow Data: ADCP profiler continuously monitors water flow velocity and flow rate. Realtime data is provided by the current meters. If the value exceeds the predetermined threshold limit, then this may trigger an early warning. This can be used, for example, to trigger an alert if the flow rate at a critical monitoring point near any populated area reaches the level that suggests a high risk of flooding, thus notifying local authorities and residents.

Water Level Prediction and Warning: The velocity data obtained from ADCP meter can be combined with other hydrological models for water level prediction. If the relationship between the flow velocities and changes in water level is known, flood levels and timings can be forecasted more accurately to prepare flood-protection measures.

Risk Management

Water Conservancy Project Scheduling Decision Support: ADCP data is useful in making decisions on the operation of water conservancy projects along the Ural River, such as small reservoirs and water-diversion structures. For instance, the measured flow data can help in deciding when and how much to release in order to balance flood-control and water-storage needs.

Assessment of Flood Disaster and Emergency Response: In cases where a flood has occurred, ADCP data can be used in post-flood assessments. It will review the sediment erosion and depositions at various sites, the bed morphology development of the river channel, and so on. The information will be provided to aid in formulation for an appropriate emergency response and a post-disaster recovery plan.

6. What's Needed for High-Quality Measurement of Ural River Currents?

For the high-quality measurement of currents in the Ural River, the equipment should have reliable materials. Since the winters are cold and there is ice and debris in the river, the casing of the ADCP profiler has to be durable enough.

The size of the equipment should be comparatively small and light to allow for easy installation and deployment at several locations along a river. It also needs to have low power consumption for continuous operation in some remote areas where power supply can be limited. The solution should be cost-effective since large-scale deployment of equipment would be necessary for comprehensive monitoring of a river.

The ADCP current profiler casing can be made from Titanium alloy. This material has very good strength and corrosion-resistant properties. Its strength enables the material to resist mechanical forces originating from the flowing water, ice impacts, and collisions with debris. The corrosion-resistant property will make sure that the performance of the equipment remains stable over time in the water-rich environment of the Ural River.

7. How to Choose the Right Equipment for Current Measurement?

Based on Purpose of Usage: Horizontal cross-section measurement of the river is best done with Horizontal ADCP (HADCP). It gives a very intricate view of the flow velocity distribution across the width of the river. Vertical ADCP is better for vertical cross-section measurement because it has the ability to measure the profile of velocity with accuracy in the vertical direction.

Different ADCPs apply to different water depth frequency ranges: An ADCP with 600 kHz works for the water depth range up to about 70 m; this may be suitable in big portions of Ural River. An ADCP working at a frequency of 300 kHz is more fitted for greater depths, until some 110 m, applicable in areas where the stream is quite deep.

There are well-known ADCP flow meter brands such as Teledyne RDI, Nortek, and Sontek. However, for a more cost-effective option, the China Sonar ​PandaADCP is worth considering. It is made of all-titanium alloy material, offering good durability and an excellent cost-performance ratio. You can find more information about it on its official website: (​https://china-sonar.com/).

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