Why We Measure the Jaipur River Flow?

1. Where is Jaipur?

Jaipur, the capital of Rajasthan state, lies in the northeastern part of Rajasthan. At approximately 26.92° latitude north and 75.88° longitude east, it is located in the semi-arid region of Rajasthan plateau. The city is rimmed by craggy Aravalli Hills, which not only add to its natural splendor but also influence its climate and water resources. The distinctive geographical position has played a significant part in shaping Jaipur as a key cultural, economic, and tourist hub of India.

Jaipur is a culturally and historically rich city with unexampled traditions. Found in 1727 by Maharaja Sawai Jai Singh II, it was the first Indian planned city. It is renowned for its stunning buildings, colloquially referred to as the "Pink City" due to its distinctive pink-coloured buildings showcasing the Rajput architectural excellence. World-renowned buildings such as the Hawa Mahal, City Palace, and Amber Fort attract tourists from around the world. Jaipur is also a center of traditional Rajasthani handicrafts, music, and art, with vibrant bazaars selling rich fabric, jewelry, and ceramic items. It has traditionally been the capital of the Kachwaha dynasty, and its legacy is seen in the city's impressive palaces, forts, and historical monuments.

As for water bodies, Jaipur has been influenced by several seasonal streams and rivers, including the Banas River. The Banas River, which is a tributary of Yamuna River, originates in the Khamnor Hills in Rajsamand district of Rajasthan. It is a seasonal river but gets filled up with water during monsoon and plays an important role in the hydrology of the area. These water bodies have played a key role in the water supply for the city, agriculture, and ecosystem as a whole but are troublesome in nature as they fluctuate.

2. What is the River Flow around Jaipur?

There are several determinants for the river flow around Jaipur. Rainfall is the major determinant, according to the semi - arid climate of the region. The period of rainy season, from June to September typically, records most of the year's rain. During this period, the streams and rivers around Jaipur experience a significant increase in water level and water velocity as run-off from the surrounding hills and plains into them. Outside of monsoons, however, these water bodies cease to exist or have a very negligible flow. Climate change has also contributed to the issue, producing more variable rainfall patterns. Some years witness very intense but short rains that cause flash floods, and some witness protracted droughs, inhibiting the natural flow regime of the rivers.

River morphology and the terrain itself also play an important part in shaping the flow. The Aravalli Hills act as a catchment area for the rains, which channel the runoff into the streams and the rivers. The wavy land causes the monsoon swift-flowing water formation that has a tendency to erode sand and rock material riverbeds. The rivers, as they travel through the plains that encircle Jaipur, spread out in widening shallower and wider channels. The river flow has also suffered very much due to human activities. Mass urbanization of Jaipur has led to the development of buildings, roads, and other structures that have disrupted the natural course of water flow. Excessive withdrawal of water from the rivers for household, industrial, and agricultural uses has been the outcome of increasing water demands. The water quality has decreased with rising industrial effluents, sewage, and agricultural runoff. All the above have taken a toll on the ecological balance of the rivers.

3. How to Measure Jaipur River Flow?

The surface drift buoy method and the anchored boat method are the conventional methods employed for river flow measurement.

The surface drift buoy method is a simple method where floats are released on the surface of the river, and their drift over a measured distance and time is recorded. This will provide an estimate of the surface velocity of flow. But this method has some serious disadvantages. It measures only the flow close to the surface, which may not in any way represent the flow in the entire water column. Also, wind and other perturbations on the surface can affect the motion of the buoys, leading to erroneous measurements.

The anchored boat method is applied by anchoring a boat at a selected position in the river. A current meter is subsequently dropped at various depths into the water to measure the velocity of flow. This method creates a more detailed profile of the flow in that location. But it is labor - intensive, time - consuming, and dangerous for safety, especially in turbulent or rapid - flowing waters. Measurement in many locations by means of this method requires a lot of manpower and equipment.

Acoustic Doppler Current Profilers (ADCPs) offer a more advanced and efficient option. ADCPs monitor the water speed at different depths across the entire water column without physical contact, i.e., non-invasive. ADCPs have the ability to generate accurate flow profiles extremely quickly, across very large sections of the river in a short time span. This makes them eminently suitable to monitor the complex and dynamic river flows surrounding Jaipur.

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

ADCPs operate based on the Doppler principle. ADCPs emit acoustic pulses into the water. The moving pulses in the water encounter moving particles, such as suspended sediment, plankton, or small animals. When the signals are bounced back from these traveling particles, the frequency of the backscattered signals changes with the particle speed relative to the ADCP. From these frequency changes, the ADCP can measure the speed of the water at different depths, creating a full profile of the river flow. This allows for precise measurement of river flow rates, directions, and overall river dynamics, offering useful information for hydrological research and water resource management.

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

For accurate measurement of river flow using ADCP at Jaipur, certain equipment properties are to be met. The material's reliability should be the topmost priority. The ADCP should be able to withstand the extreme river environment, which includes exposure to sediment-carrying water, fluctuating water temperatures, and potential impacts with floating objects. Corrosion-resistant, high-grade materials such as titanium or specifically designed polymers give the device ruggedness and longevity.

Size and weight are considerations as well. A small, light ADCP is more portable and can be deployed easier, especially in the sometimes hard - to - reach river sections near Jaipur. Portability makes data collection easier between the different sections of the rivers.

Cost-effectiveness is also of utmost priority. In the case of extensive or long-term monitoring assignments in Jaipur, an expensive ADCP with a reasonable price is preferable. This ensures that thorough monitoring of the river current is available without costing an arm and a leg, facilitating repeated and minute analysis of the river behavior.

6. How to Choose the Right Current Measurement Equipment?

Deployment Methods

• Mobile boat ADCP: Ideal for conducting surveys, examining river discharges, and deriving detailed flow maps. It can quickly survey long stretches of Jaipur's rivers and collect data from numerous disparate points within a short span of time, thereby providing an entire picture of the river flow patterns.
• Bottom - fixed (fixed) ADCP: Best suited for long - term continuous measurement at specific locations. Placed at the bottom of the river, it is able to collect data over extended periods, offering valuable information about long - term trends and patterns of the river flow.
• Cableway ADCP: In sections of the river where there is a cableway, a cableway ADCP may be used to measure the flow across the river at a point. This is a good way of obtaining precise and reproducible flow measurements at key points in the river and utilizing these for calibration and validation of other measurement systems.

Working Frequency

The working frequency of an ADCP will dictate its range and resolution. A 600 kHz ADCP with a maximum range of 70 meters may be employed for rather shallow parts of the rivers near Jaipur or for making high-resolution measurements in deeper water courses. A 300 kHz ADCP with a maximum range of 110 meters is better employed for deeper water courses of the rivers. The frequency must be chosen in accordance with the specific river conditions and measurement requirements, such as the level of detail to be obtained and the highest water column depth for the measurement.

Brand Recommendations

The world - recognized ADCP brands include Teledyne RDI, Nortek, and SonTek. They deal with high - end ADCPs with advanced technology and proven reliability. For an affordable choice, the Chinese brand "China Sonar Panda ADCP" is suggested. This "economy ADCP," made of all - titanium alloy material, is resistant and long - lasting in Multan's harsh river environment. It is low - cost - effective, and a well - suited choice for local research projects to city - wide water management projects. To learn more, visit their website at https://china-sonar.com/.

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