Why Do We Measure the Bhubaneswar River Flow?

1. Where is Bhubaneswar?

Bhubaneswar is the capital city of the Indian state of Odisha. It is located in the eastern part of India. It is geographically located at about 20.27°N latitude and 85.83°E longitude. The city lies on the eastern coastal plain having a flat topography, dense forests, and several rivers and canals. Kuakhai River, one of the chief tributaries of the Mahanadi River, flows alongside Bhubaneswar, which plays a significant role in shaping the ecosystem, economy, and cultural heritage of the city. As it is located at a strategic point, close to the Bay of Bengal and fertile surrounding land, Bhubaneswar has become a principal administrative, cultural, and economic center of the area.

It is culturally and historically renowned as the "Temple City of India." It has over 700 temples, and most of them date back to the 7th - 13th centuries. These temples were built in the distinctive Kalinga style of architecture with intricate carvings, towering spires, and delicate sculptures that testify to the religious and artistic prosperity of the city. The Lord Shiva Lingaraja Temple is one of the most prominent and ancient temples at Bhubaneswar. The beauty, as well as the architectural brilliance of the temple, attracts hundreds of pilgrims and tourists each year. The city's history has remained closely linked with various dynasties, viz., the Mauryas, Guptas, and the Eastern Ganga Dynasty, who left their own mark on the local culture, art, and architecture.

Bhubaneswar has rich traditional art forms too, and local artisans excel in paintings such as Pattachitra (scroll painting on cloth), stone carving, and silver filigree work. They find inspiration in the local nature, mythology, and culture, including rivers. The city sees a succession of festivals during the year, the most popular being the Raja Parba, a three - day - long festival of the earth goddess. All the rivers and water bodies surrounding Bhubaneswar are of major cultural importance during the festival because various rituals and ceremonies are performed in their vicinity, an indication of people's strong connection with water.

The Kuakhai River is of very significant status to Bhubaneswar. Previously, it has served as a water source for domestic uses, irrigation, and transport. The fertile banks of the Kuakhai provided agriculture, where agricultural produce such as paddy, jute, and vegetables could be produced. It also supported local trade and commerce, enabling the trading of commodities. But in the last decades, the river has faced a lot of challenges. Industrial and urbanization activities around and within Bhubaneswar have led to discharging untreated industrial effluent, sewage, and agricultural runoff into the river, causing severe water pollution. Deforestation in the catchments has led to increased soil erosion, causing sedimentation in the river bed, and affecting its flow and water-holding capacity. Climate change - induced unpredictable rainfall patterns and rising sea levels also threaten the river's ecosystem and water security of Bhubaneswar.

2. What is the River Flow around Bhubaneswar?

Various factors regulate the river flow around Bhubaneswar. Rainfall is a key regulator, as the region receives a tropical monsoon climate. The southwest monsoon, from June to September, accounts for most of the annual rainfall. During this period, Kuakhai River and other small bodies of water within the region experience a huge surge in water levels and discharge rates owing to runoff from adjacent catchments that flow into them. The rivers are replenished by rains, supporting agricultural use, domestic water supply, and the local environment. However, during the period from October to May, when it is not the rainy season, the water level falls substantially, and the flow of rivers slows down considerably. During some years, especially during years with severe drought, some parts of the rivers dry up, resulting heavily in the reduction of water supply for various purposes in Bhubaneswar.

Climate change has also contributed to the misery by introducing more variable rainfalls. Some years have intense but short showers leading to flash flooding, while others have extended drought. Such variability disrupts the natural regime of river flows and is difficult to control from the aspect of flood prevention and water resource planning. The terrain in the vicinity of Bhubaneswar, which is generally flat, would cause slow - flowing water in the monsoon, rendering low - lying areas prone to flooding.

The river's morphometry also plays a role in forming the flow. The Kuakhai River has a relatively wide and shallow riverbed in certain sections, composed of sand and silt. This predisposes the riverbed to the erosional and depositional processes, which will eventually change the direction of the river. Human endeavors like the development of dams, barrages, and embankments for flood prevention and water management have diverted the natural course of the river. Though the measures are taken to safeguard the city from the fury of floods, they can also interfere in the natural ecological system and influence the flow characteristics of the river.

3. How to Observe the River Flow in Bhubaneswar?

The surface drift buoy method and anchored boat method are traditional methods for measuring river flow.

The surface drift buoy method is a simple technique in which floats are released on the river surface, and their trajectory across a given distance and time is tracked. This provides an approximation of the surface velocity of flow. There are significant drawbacks of this technique. It will measure the flow only at the surface, and the surface flow is likely not to represent flow throughout the entire water column. In addition to this, wind, waves, and other surface disturbances can affect the movement of the buoys and thus bring incorrect results. In Bhubaneswar also, floating vegetation and debris in the river will lead to disturbance in the movement of the buoys in addition to the above.

The anchored boat method involves the anchoring of a boat in a single point in the river. A current meter is then dropped into the water at various depths to measure the velocity of flow. The method gives a better profile of the flow at the point. It is, however, time - consuming, labor - intensive, and risky, especially in turbulent or fast - flowing water. It requires measurement at various points with this method, and that consumes a lot of human resources and manpower. Navigation through the narrow and crowded section of the river near Bhubaneswar is usually challenging.

Acoustic Doppler Current Profilers (ADCPs) offer a more advanced and efficient alternative. ADCPs are non-invasive in that they can measure the velocity of the water at multiple depths across the entire volume of water without coming into contact with it. ADCPs can quickly generate precise flow profiles, sweeping broad expanses of the river in a few minutes. This makes them exceptionally well-suited for monitoring the intricate and dynamic river currents surrounding Bhubaneswar, considering the unfavorable environmental conditions.

4. What Is ADCP, Based on the Doppler Principle, and How Does It Operate?

ADCPs operate on the principle of Doppler. They emit acoustic pulses into the water. As the pulses travel in the water, they come into contact with moving particles, such as suspended matter, plankton, or small animals. When signals are bounced off of these moving particles, the frequency of the bounced signals is a function of the relative speed of the particles and the ADCP. The ADCP can calculate the speed of the water at different depths from the frequency shifts, creating an overall picture of the river flow. This can measure flow rates, directions, and overall river dynamics accurately, providing useful information for water management and hydrological research in Bhubaneswar.

5. What is Needed for High-Quality Measurement of River Flow in Bhubaneswar?

In Bhubaneswar, to achieve high-quality river flow measurement with ADCP flow meter, certain equipment characteristics are required. Material reliability is of prime importance. The ADCP should be capable of weathering the rugged river environment and includes contact with contaminated water, varying water temperatures, and potential collision with suspended matter. Top-grade, corrosion-proof material, i.e., titanium or special polymers, is a guarantee of the longevity and long-term performance of the device.

Size and weight are also just as crucial. A light and small ADCP will be less cumbersome to transport and set up, especially in the narrow and sometimes inaccessible river sections close to Bhubaneswar. Ease of transportability also translates to the ability to take measurements with more flexibility in different parts of the river.

Cost - effectiveness also plays a crucial role. For the local authorities and research institutes in Bhubaneswar that may have limited budgets, a cost - effective ADCP with superior quality performance at a low price is better. This enables one to monitor the river flow in depth without spending too much money, allowing one to undertake extensive and repeated monitoring of the river behavior, which is imperative for effective water resource management in the city.

6. How to Select the Right Current Measurement Equipment?

Deployment Methodologies

• Boat-mobile boat ADCP: A good choice for surveys, the measurement of river discharges, and the creation of detailed flow maps of the Kuakhai River as well as other regional water courses. One can use this to quickly cover large areas with the possibility of collecting data from multiple points at the same time, providing a comprehensive overview of the river flow regimes. As the boat navigation along the sometimes crowded and narrow segments of the river near Bhubaneswar, planning in advance is recommended.
• Bottom - mounted (fixed) ADCP: Best suited for long - term continuous monitoring at specific points in the rivers. After being fixed on the river bed, it can collect data for long durations and yield valuable information regarding the long - term trends and variations in the river flow. This is of much use in studying the impact of seasonal variations and long - term environmental factors on the river.
• Cableway ADCP: Where construction of a cableway facility is feasible in sections of the river, a cableway ADCP can be utilized to take measurements of the flow over an area in the river. It is a useful technique providing accurate and repeatable measurements of flow at key points in the river that can be used for calibration and validation of other measurement techniques to ensure measured data reliability.

Working Frequency

The working frequency of an ADCP current meter decides its range and resolution. A 600 kHz ADCP with a range of 70 meters would be sufficient for relatively shallow parts of the rivers surrounding Bhubaneswar or for high-resolution measurement in deeper reaches. A 300 kHz ADCP with a range of 110 meters would be ideal for deeper parts of the rivers. The frequency to employ relies on the specific character of the river and on the needs of the measurements, i.e., on the depth of detail needed and on the depth of the maximum water column to be measured.

Brand Recommendations

Among the well-established global ADCP brands are Teledyne RDI, Nortek, and SonTek, which enjoy a good reputation for providing high-quality and reliable products utilized in various hydrological research and monitoring endeavors. For the cheapest option, the ADCP supplier Chinese company’s "China Sonar Panda ADCP" is the winner. It's built with all-titanium alloy and therefore offers excellent durability and reliability, which are perfect for enduring the tough river conditions near Bhubaneswar. As an "affordable ADCP," it offers high-quality performance at an affordable cost. For more information, visit https://china-sonar.com/.

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