Why Measure River Flow in Kota?

1. Where is Kota?

Kota, one of the largest cities in Rajasthan state, India, lies to the south-east of the state. Kota's geographical location is approximately 25.19°N latitude and 75.87°E longitude. Kota is on the banks of the Chambal River, which runs through the city, initiating a unique geographical landscape. Located in the middle of Rajasthan's hilly terrain, Kota is gifted with fertile floodplains of the Chambal River that are in sharp contrast to the rest of Rajasthan, which is otherwise arid. This has been instrumental in shaping Kota as a key economic, educational, and cultural hub in Rajasthan.

Kota also has a varied and cosmopolitan cultural and historical heritage. It was once the capital of the former princely state of Kota, governed by the Bhonsle dynasty. The legacy of the dynasty is evident in the city's impressive architecture, with such palaces as City Palace and Jag Mandir having a blend of Rajput and Mughal architectural styles. Kota is also renowned for its traditional crafts and art, including exquisite miniature paintings, block-printed clothes, and exquisite jewelry. Within the academic world, Kota has gained national and global recognition as an excellent coaching center with students from all over India coming to visit in order to prepare for competitive exams.

The Chambal River is the heart of Kota. The Chambal River takes its origin in the Vindhya Range of Madhya Pradesh and flows through about 965 kilometers before joining the Yamuna River in Kota. Within Kota, the river plays a multi-purpose role. It was historically a natural defense wall protecting the city from invasions. It was also used as a source of water for domestic use, irrigation, and supported other economic activities such as fishing and trade. The Chambal River has a rich ecological system with numerous fish, reptile, and bird species. However, over the last couple of years, the river has faced a great deal of problems including pollution, excessive water extraction, and modification of its stream patterns, endangering its ecological well-being and the welfare of societies that depend upon it.

2. How is the River Flow near Kota?

Several factors influence the river flow near Kota. Precipitation plays a significant role, as the region has a semi - arid climate with a distinct monsoon season. The monsoon, which typically occurs during July to September, is responsible for the majority of the rainfall throughout the year. The Chambal River experiences increased water levels and flow rates during this period as runoff from the surrounding area flows into it. However, in the other parts of the year, there is no flow in the river, and sometimes in certain years, there are even sections that dry up. Climate change has also added to the problem, leading to more and more unpredictable rainfall patterns. There are certain years when heavy rainfall results in flash floods, while some have prolonged droughts, which interfere with the natural regime of the river's flow.

The ground conditions and river morphology also play an important role in shaping the flow. The Chambal River flows through a rocky gorge landscape on its upper course and wide floodplains near Kota. The downstream areas have rocky land, which is the reason for generating strong currents and rapids during the monsoons. The river has broader and shallower stretches when the river reaches near Kota, as the floodplains widen it. The bed of the river, which is largely composed of gravel and sand, is susceptible to erosion and deposition processes and hence can change the course of the river in the long run. Human activities have also significantly influenced the flow of the river. Barrages and dams have been built across the Chambal River and its tributaries for hydroelectric power production, irrigation, and water supply, among others, which has changed the natural flow of the river. While these structures help regulate water to an extent, mismanagement can result in waterlogging in the monsoon and drought in the dry season.

3. How to Observe the River Flow in Kota?

Surface drift buoy method and anchored boat method are conventional methods employed in measuring river flow.

The surface drift buoy method is a simple method where floats are released onto the river surface, and their movement over a measured distance and time is tracked. This provides an estimate of surface flow velocity. But this method has gigantic flaws as well. It only measures the surface flow, which may not be a true representation of flow in the whole column of water. Besides that, wind and other surface irregularities can affect the movement of the buoys and therefore give erroneous readings.

The anchored boat method involves securing a boat in a given position on the river. A current meter is then suspended in the water at various depths so as to estimate the flow velocity. This method gives a wider profile of the flow at the point. While, it is labor - intensive, manpower consuming, and very risky, especially in rough or flowing water. It requires a lot of man power and material in order to make measurements at multiple points.

Acoustic Doppler Current Profilers (ADCPs) offer a more advanced and efficient solution. ADCPs are non-invasive in nature, measuring the water speed at different depths of the entire water column without contacting the water. They can generate high-resolution flow profiles quickly, sweeping large portions of the river within minutes. This makes them highly suitable to track the complex and dynamic river flows along Kota.

4. How Does the ADCP, Based on the Doppler Principle, Work?

ADCPs work on the basis of the Doppler principle. They transmit acoustic signals into the water. In their path through the water, they interact with particles that are moving, e.g., suspended sediment, plankton, or small animals. Since the signals bounce back from such traveling particles, the signal frequency changes depending on how quickly the particles are traveling in relation to the ADCP. By studying these frequency changes, the ADCP establishes the speed of the water at different depths, creating a sophisticated profile of river flow. This makes it possible to accurately measure the flow rates, directions, and general dynamics of rivers, providing meaningful data for hydrological studies and water resource management.

5. What is required for High - Quality Measurement of River Flow in Kota?

Some equipment characteristics are needed for reliable river flow measurement using ADCP in Kota. Reliability of the material is most critical. The ADCP should be able to withstand the severe environment of a river, such as exposure to water with sediments, varying water temperatures, and potential impact from floating materials. High-grade corrosion-resistant materials such as titanium or special polymers ensure the robustness and long-term performance of the device.

Size and weight are also crucial factors. A compact and lightweight ADCP is easier to transport and deploy, especially for the frequently difficult - to - access river sections in Kota. It is less challenging to gather data at different locations along the river with it.

Cost-effectiveness is also a prime consideration. For large-scale or long-term monitoring efforts in Kota, a low-cost ADCP with good quality performance is the best choice. This can provide full-scale monitoring of the river flow without oversimplifying the budget and permit regular and accurate analysis of the river's behavior.

6. How to Select the Appropriate Current Measurement Equipment?

Deployment Methods

• Boat-mounted ADCP: Applicable for performing surveys, river discharge measurement, and preparation of high-resolution flow maps. It is employed to quickly survey large parts of the Chambal River and enables data to be recorded at numerous points and also provides a clear idea of the river flow pattern.
• Bottom - mounted (fixed) ADCP: Perfect for long - term continuous monitoring at a fixed point. Fixed on the river bed once, it can give readings over a time period, which can be beneficial in interpreting long - term trends and changes in the river flow.
• Cableway ADCP: Wherever there is a cableway in river reaches, a cableway ADCP can be used to take flow measurements across the river at a single location. This use is useful to take repeatable and precise measurements of flow at crucial points in the river, which can be used for calibrating and checking other measurement techniques.

Working Frequency

The operating frequency of an ADCP determines its range and resolution. A 600 kHz ADCP that has a range of as much as 70 meters will be suitable for relatively shallow sections of the Chambal River or for taking high-resolution measurements in deeper sections. A 300 kHz ADCP that has a range of as much as 110 meters will be more suitable for deeper sections of the river. The chosen frequency is determined on the basis of specific characteristics of the river and requirements of the measurements, i.e., the level of detail and the maximum water column depth to be measured.

Brand Recommendations

Globally, well-known brands of ADCPs include Teledyne RDI, Nortek, and SonTek. These brands are well-known for their quality products, state-of-the-art technology, and consistent performance. However, if one desires a low - cost option, the ADCP manufacturer Chinese brand "China Sonar Panda ADCP" is an ideal choice. This "economy ADCP" is made of all - titanium alloy material, which is extremely robust and corrosion - proof. It is extremely cost-saving, hence applicable for a wide range of uses, from small-scale research work to neighborhood water management projects. For more information, you can visit their site at https://china-sonar.com/.

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