Why We Need to Measure the River Flow of Azad Jammu and Kashmir？

1. Where is Azad Jammu and Kashmir?

Azad Jammu and Kashmir (AJK) is a self-governing administrative territory of Pakistan, located in the north of the country. Its geographical location is in the Pir Panjal and Himalayan mountain ranges, with a beautifully scenic and diverse terrain. The region is characterized by snow-covered, high-altitude mountains, valleys, lush green meadows, and numerous glaciers. The region's topography is very diverse, with the regions along the rivers being comparatively low-lying and enormous snow-covered peaks for almost all of the year. This topography, apart from contributing to its visual beauty, deeply influences its climate, water resources, and overall ecosystem.

Whereas cultural and human significance goes, AJK is replete with an affluent and affluent history. It has been a culturally mixed region with diverse ethnic groups and has Pathan, Punjabi, and Kashmiri influences. Locally dominant culture is firmly established with handicrafts, music, and dance culture. Folk music, especially soulful Kashmiri songs, and traditional dances like the Rouf, are a part of the affluent culture. Geographically, the region has been a strategic crossing point as well, with different regions of the Indian subcontinent and Central Asia connected by routes of trade that enabled the movement of goods, ideas, and religions.

Azad Jammu and Kashmir's principal river system is the Jhelum River. The source of the Jhelum River is the Verinag Spring, located in Indian-administered Jammu and Kashmir. It then flows northwest across AJK, slicing through the hilly country. The river flows its way through the region, acting as a lifeline to the people. It ultimately joins the Chenab River, which in turn flows into the Indus River and empties into the Arabian Sea. The Jhelum River is unparalleled in significance for AJK. It is a significant source of freshwater for domestic use, farm irrigation, and industry. The fertile plains on the banks are used to support a great deal of agriculture in the region, including wheat, rice, and fruit being cultivated. The river has hydroelectric power potential, which can be used to augment the energy needs of the region as well as economic development. Along the towns and cities of AJK, the Jhelum River and its tributaries form a network of streams. Estuarine-like conditions prevail in certain areas around the confluence points, which support diversified water life and contribute towards maintaining the ecological balance in the region.

2. How is the River Flow Near Azad Jammu and Kashmir?

Influence Factors

• Precipitation and Runoff: Azad Jammu and Kashmir has a varied climate, with strong seasonal variation of rainfall. The mountainous zone of the region receives a major portion of its rainfall during the monsoon, which usually takes place in July to September. Heavy monsoon rainfalls can result in river rise and velocities of flow to accelerate at a very high rate. Snowfall is also common in the high altitude of the region in winter months. When the snow melts in spring and early summer, it contributes a great deal of water to the rivers, and there is another peak in the river flow. These fluctuations in rainfall and snowmelt- induced runoff in different seasons have a direct and sizable impact on the Jhelum River's water supply and mode of flow along with its tributaries.
• Topography and River Morphology: AJK's rugged topography plays a significant role in the determination of the river flow. The Jhelum River has to traverse steep gorges, narrow valleys, and extensive floodplains. In mountainous land, the river gradient is steep, and the river thus has high-speed flowing water with high erosive power. When it enters the plains, the slope decreases and the river broadens, decreasing the speed of flow. The river bed is made of a mixture of rocky, gravelly, and sandy materials that affect the roughness and resistance to flow. The meandering course of the river also creates zones of differing flow characteristics, including a faster-flowing stream on outer bends and slower-flowing water on inner bends.
• Reservoir Operation: There are a number of dams and reservoirs on the Jhelum River and its tributaries within AJK as well as further up in Indian-controlled Jammu and Kashmir. These reservoirs are used for various purposes such as flood regulation, storage of water to irrigate, and hydroelectric power generation. The response of these reservoirs can be highly influential on the downstream river discharge. For example, during the monsoon season, reservoirs can discharge water in a regulated manner to prevent downstream flooding, but in the dry season, they can regulate the flow to supply water continuously for various purposes.

Historical Hydrological Events

Among the historical floods that occurred in Azad Jammu and Kashmir, one of the significant ones was in the year 2014. According to a report submitted by the United Nations Office for the Coordination of Humanitarian Affairs, https://reliefweb.int/report/pakistan/pakistan-floods-2014-initial-damage-assessment-and-requirements, monsoon rains led to severe and widespread flooding across the region. The Jhelum River overflowed its banks, inundating large tracts of land, including villages and towns. Thousands of homes were destroyed or damaged, and numerous individuals were displaced from their households. Farmlands were inundated, causing heavy crop losses and impacting the local economy. This event also highlighted the need for adequate monitoring of river flow to predict and mitigate the impact of such floods. Droughts have also affected the area intermittently, leading to a lack of water for household, farm, and industrial uses. River flow observation helps in understanding the water availability during such periods of drought and in planning for water conservation and water management.

3. Observation of the River Flow of Azad Jammu and Kashmir

Traditional Methods

• Surface Drift Float Method: The surface drift float method is a primitive and simple method for measuring river flow. A float such as a small buoy or a piece of wood is placed on the river surface. The time that the float moves a given distance is recorded and, from that, surface water velocity may be calculated. But this technique will only provide information on the surface flow and does not account for velocities at different depths in the water column. Secondly, wind and surface turbulence might also induce a distortion of the motion of the float with incorrect velocity readings.
• Anchored Boat Method (Manning Table/Current Meter): anchored boat method includes securing a boat to a position in the river. A current meter is then lowered into the water at various depths to measure the water velocity at various positions in the vertical profile. By taking measurements at multiple points along the river cross-section, it is possible to build a definite picture of the flow at that particular spot. While it holds the potential to provide detailed information, this method is highly time - consuming, labor - intensive, and dangerous, especially in turbulent or high - speed waters.
• *Introduction to ADCP: Acoustic Doppler Current Profiler

The Acoustic Doppler Current Profiler (ADCP) gives a higher level of sophistication and effectiveness as a solution to measuring river flow in Azad Jammu and Kashmir. Unlike traditional measurements, ADCP can measure the velocity of the water at several levels simultaneously, resulting in a continuous profile of the water column. It is non-invasive, and thus risk to equipment or personnel is avoided. ADCP can quickly obtain large amounts of data, making it suitable for large-scale river surveys and real-time observation, which is crucial to the understanding and control of the complex river flow behavior in the region.

4. What Is the Working Principle of ADCP Based on the Doppler Principle?

The ADCP operates based on the Doppler principle. It emits acoustic pulses into the water column. These signals are disseminated by suspended water particles, such as sediment and plankton. If moving water, the rate of the backscattered acoustic signals changes. The ADCP can identify the velocity of water at different depths by precisely quantifying this change in frequency, or Doppler shift. The system employs a number of transducers that transmit and receive acoustic signals in different directions, enabling it to accurately determine the three-dimensional flow velocities of the flow in the water column. All the data is then computed to generate detailed flow maps and profiles of the river.

5. What Does One Need for High - Quality Measurement of River Flow in Azad Jammu and Kashmir?

Equipment Requirements

• Material Reliability: Because of the adverse AJK environment, featuring high-velocity rivers, abrasive sediments, and varying water chemistry, high-quality ADCP equipment must be fabricated from very reliable materials. Corrosion-resistant, erosion-resistant, and impact-resistant materials are essential in order to give longevity and accurate operation of the ADCP.
• Light Weight and Compact Size: Given the mountainous and inaccessible topography of AJK, ADCP hardware must be compact and light in weight. This allows easy transportation and deployment at remote locations, enabling researchers and technicians to travel to different sections of the river system and take accurate measurements.
• Cost - Effectiveness: Cost-effective ADCP instruments are required for large-scale use in Azad Jammu and Kashmir. It allows increased coverage of the river current without putting a burden on the limited economic resources of the area, so that critical hydrological information can be accessed for better water management and avoidance of disaster.

6. How to Choose the Right Current Measurement Instruments?

Deployment Methods

• Boat - Mounted (Moving Boat) ADCP: A boat-mounted ADCP can be used for conducting detailed river surveys, discharge measurement, and flow map generation. The ADCP can scan large areas of the river very fast and generate a general map of the flow characteristics over different reaches. An ADCP can be employed for preliminary investigations as well as measuring the general flow patterns of the Jhelum River and its tributaries.
• Bottom - Mounted (Fixed) ADCP: Bottom - mounted ADCP is utilized to track long - term continuous river flow. It can be installed at strategic locations in the river and continue recording flow data continuously for extended periods of time. This data is invaluable in tracking long - term trends, seasonal variations, and the impact of various factors on river flow.
• Ropeway ADCP: If ropeways are present over the river, a ropeway ADCP can be used to obtain accurate measurements. It allows one to conduct precise river flow profiling over the whole width of the river, providing minute information that can be used for various hydrological research and water management purposes.

Working Frequency

The selection of working frequency in an ADCP is an extremely important consideration. A 600 kHz ADCP typically has about a 70-meter range and is therefore useful for very shallow to medium-depth rivers. A 300 kHz ADCP has a range of up to 110 meters, which is preferable for the deeper parts of the river. Higher frequencies provide better resolution but less range, while low frequencies provide greater range but worse resolution. The frequency to be employed will need to be determined by the specific characteristics of the river, such as depth and how fine a detail is required in the measurement.

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.