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Past Questions — 2025
Population forecasting using Arithmetic increase method is suitable for:
A)
Cities with rapid growth
B)
Small towns, slow growth
C)
Developing cities
D)
Decreasing trend in growth
The Arithmetic Increase Method assumes that the population increases by a constant amount each decade, regardless of the current population size.
1. **Why Option (b) is correct**: This method is most suitable for old, established cities or small towns where the growth rate has stabilized and is slow. In such cases, the population growth is linear rather than exponential.
2. **Why Option (a) and (c) are incorrect**: Cities with rapid growth or developing cities typically experience exponential or geometric growth. For these, the Geometric Increase Method or the Incremental Increase Method is used, as these methods account for the compounding effect of population growth.
3. **Why Option (d) is incorrect**: While the arithmetic method can technically be used for a decreasing trend (negative constant increase), it is specifically designed to forecast steady, slow growth in stable urban environments, not specifically to model declining populations.
HDPE pipes are mostly preferred for:
A)
Electrical wiring
B)
Portable water supply due to flexibility
C)
Sewer lines only
D)
Road construction
HDPE (High-Density Polyethylene) pipes are widely preferred for potable water supply systems for several technical reasons: 1. Flexibility: They can bend to accommodate terrain changes, reducing the number of joints required. 2. Corrosion Resistance: Unlike metal pipes, HDPE does not rust or corrode, making it ideal for transporting drinking water. 3. Durability: It is resistant to chemical degradation and impact. 4. Leak-proof joints: Heat-fused joints create a monolithic system that prevents leakage.
Analysis of other options:
- Option (a): While HDPE can be used as conduits for electrical cables, it is not the 'most preferred' use case in the context of Public Health Engineering (PHE) piping materials.
- Option (c): While HDPE can be used for sewers, it is not used 'only' for sewer lines; its primary advantage in PHE is often water distribution.
- Option (d): HDPE is a piping material, not a primary material for road construction (which uses bitumen, concrete, etc.).
MLD in water supply stands for:
A)
Multi Litres per day
B)
Maximum litres per day
C)
Millilitres per day
D)
Million litres per day
In water supply and wastewater engineering, MLD is a standard unit of measurement used to quantify the capacity of water treatment plants, the volume of water demanded by a city, or the flow rate of a distribution system.
1. 'M' stands for Million (10^6).
2. 'L' stands for Litres.
3. 'D' stands for Day.
Therefore, 1 MLD = 1,000,000 litres of water per 24-hour period.
Analysis of other options:
- Option (a) 'Multi Litres' is not a recognized technical term in hydraulics.
- Option (b) 'Maximum litres' refers to a peak value, not a unit of measurement.
- Option (c) 'Millilitres' is a very small unit (1/1000 of a litre) and is not used to measure municipal water supply volumes.
Which one of the following is not a coagulant used in water treatment plant?
A)
Polyaluminum Chloride (PAC)
B)
Ferric Chloride
C)
Aluminum sulphate(Alum)
D)
Bleaching powder
Coagulants are chemicals added to water to neutralize the electrical charge of colloidal particles, allowing them to clump together (flocculate) and settle out of the water.
1. Polyaluminum Chloride (PAC) is a high-efficiency inorganic polymer coagulant widely used in modern water treatment.
2. Ferric Chloride (FeCl3) is a common iron-based coagulant used to remove turbidity and organic matter.
3. Aluminum sulphate (Alum) is the most traditional and widely used aluminum-based coagulant in water treatment plants.
4. Bleaching powder (Calcium hypochlorite) is a strong oxidizing agent used primarily for disinfection (killing bacteria and viruses) and oxidation, not for coagulation. It does not possess the cationic properties required to destabilize colloidal particles. Therefore, it is not a coagulant.
Which one of the following is a reinforced material?
A)
Plain Cement Concrete
B)
Brick
C)
Reinforced Cement Concrete
D)
Stone
A reinforced material is a composite material consisting of a matrix (the bulk material) and a reinforcement (usually fibers or bars) to improve its mechanical properties, specifically to increase tensile strength.
1. **Reinforced Cement Concrete (RCC)**: Concrete is very strong in compression but weak in tension. To overcome this, steel bars (reinforcement) are embedded in the concrete. The combination of concrete (matrix) and steel (reinforcement) makes it a reinforced material. This is the correct answer.
2. **Plain Cement Concrete (PCC)**: This consists only of cement, aggregates, and water. It lacks any internal reinforcement and is therefore not a reinforced material.
3. **Brick**: This is a ceramic material made from fired clay. It is a homogeneous material (in terms of structural composition) and not reinforced.
4. **Stone**: This is a natural geological material. While it has internal mineral structures, it is not a 'reinforced material' in the engineering sense of adding a secondary material to enhance properties.
Multistage centrifugal pumps are used to obtain:
A)
high discharge
B)
high head
C)
pumping of viscous fluids
D)
high head and high discharge
A centrifugal pump is a kinetic machine that converts rotational energy into pressure head. In a single-stage centrifugal pump, the head (pressure) developed is limited by the impeller diameter and the rotational speed. To achieve a higher head without excessively increasing the impeller size or speed, multiple impellers are arranged in series. In a multistage centrifugal pump, the discharge of the first stage becomes the suction for the second stage, and so on. Consequently, the total head produced is the sum of the heads produced by each individual stage (Total Head = n × Head per stage, where n is the number of stages).
Why other options are incorrect:
- (a) High discharge: To increase discharge (flow rate), one would typically increase the impeller size or use pumps in parallel, not in series (multistage).
- (c) Pumping of viscous fluids: Centrifugal pumps are generally inefficient for highly viscous fluids; positive displacement pumps (like gear or screw pumps) are used for this purpose.
- (d) High head and high discharge: While some large pumps can do both, the specific defining purpose of 'multistaging' is to increase the head. Increasing discharge is handled by the pump's capacity/diameter, not by adding stages.
The main purpose of a soak pit in rural sanitation is to:
A)
Allow percolation of wastewater
B)
Store drinking water
C)
Trap solid waste
D)
Collect rainwater
A soak pit (also known as a seepage pit) is a covered, porous-walled chamber that allows wastewater—typically from a septic tank or greywater sources—to slowly soak into the surrounding soil. The primary mechanism is percolation, where the soil acts as a natural filter to treat the effluent before it reaches the groundwater table.
Why other options are incorrect:
- Option b: Drinking water is stored in tanks or reservoirs, not soak pits, as soak pits are designed for waste disposal.
- Option c: Trapping solid waste is the primary function of a septic tank or a grease trap; a soak pit is designed for liquid effluent. If solids enter a soak pit, they can clog the soil pores (biomat formation), leading to failure.
- Option d: While rainwater harvesting pits exist, a 'soak pit' in the context of rural sanitation specifically refers to the disposal of wastewater.
Which welding process is most commonly used for joining steel water supply pipes on-site?
A)
Arc welding (SMAW)
B)
MIG welding
C)
TIG Welding
D)
Laser welding
Step-by-step reasoning: 1. Analysis of the environment: The question specifies 'on-site' joining of steel water supply pipes. On-site conditions typically involve outdoor environments, wind, dust, and limited access to controlled laboratory settings. 2. Evaluating SMAW (Shielded Metal Arc Welding): SMAW is the most common process for field work because the equipment is portable, it does not require external shielding gas (which would be blown away by wind), and it is highly versatile for various steel thicknesses. 3. Evaluating MIG (Metal Inert Gas) welding: MIG requires a heavy gas cylinder and a regulator to provide shielding gas. This makes it cumbersome for on-site pipework and susceptible to wind interference. 4. Evaluating TIG (Tungsten Inert Gas) welding: TIG is a slow, high-precision process requiring extreme cleanliness and a stable environment. It is generally used in shops for high-pressure or specialized alloy piping, not for general on-site steel water supply pipes. 5. Evaluating Laser welding: This is an industrial, high-cost process requiring massive capital investment and a controlled factory environment; it is not used for field installation of water pipes. Therefore, SMAW is the most practical and commonly used method for on-site steel pipe welding.
Which one of these is not a component of rural sanitation?
A)
Soak pit
B)
Night soil disposal
C)
Septic tank
D)
Storm water drain
Rural sanitation primarily focuses on the management of human excreta and wastewater (greywater) to prevent disease and environmental contamination.
1. Soak pits (Option a) are used for the disposal of effluent from septic tanks or greywater in rural areas.
2. Night soil disposal (Option b) refers to the collection and removal of human excreta from pit latrines, a key aspect of sanitation management.
3. Septic tanks (Option c) are onsite wastewater treatment systems commonly used in rural settings where centralized sewerage is unavailable.
In contrast, Storm water drains (Option d) are designed to manage surface runoff from rain. While they are a part of general civil infrastructure and urban drainage systems, they are categorized under 'Drainage' or 'Hydrology' rather than 'Sanitation' (which specifically deals with waste and hygiene). Therefore, storm water drainage is not a component of the sanitation cycle focused on waste disposal.
The daily clear water demand of rural area having a population of 420 souls at water supply level of 55 lpcd is:
A)
25,000 litres
B)
28,500 litres
C)
23,100 litres
D)
2,30,000 litres
To calculate the daily clear water demand, we use the following formula:
Daily Water Demand = Population × Per Capita Water Supply Rate
Given data:
1. Population = 420 souls
2. Water supply level (Per capita demand) = 55 lpcd (litres per capita per day)
Calculation:
Daily Demand = 420 souls × 55 litres/soul/day
Daily Demand = 23,100 litres/day
Comparing this result with the given options:
- Option (a) 25,000 litres is incorrect.
- Option (b) 28,500 litres is incorrect.
- Option (c) 23,100 litres matches our calculation exactly.
- Option (d) 2,30,000 litres is incorrect (likely a decimal placement error).
Therefore, the correct answer is 23,100 litres.
Which structure is built for retaining soil?
A)
Septic tank
B)
Soak pit
C)
Infiltration gallery
D)
Retaining wall
Step-by-step reasoning:
1. Analysis of the requirement: The question asks for a structure specifically designed to 'retain soil'. In civil engineering, this refers to resisting the lateral pressure of soil when there is a difference in ground elevation.
2. Evaluating Option (a) Septic tank: A septic tank is a watertight underground container used for the primary treatment of sewage. Its purpose is waste decomposition, not soil retention.
3. Evaluating Option (b) Soak pit: A soak pit is a covered sloping pit that allows effluent to soak into the ground. It is a drainage structure, not a soil-retaining structure.
4. Evaluating Option (c) Infiltration gallery: An infiltration gallery is a horizontal structure used to collect groundwater from a permeable aquifer. It is used for water sourcing, not soil retention.
5. Evaluating Option (d) Retaining wall: A retaining wall is a structure specifically engineered to hold back soil (earth) to prevent slope failure or to create level terraces on sloped terrain. It resists the lateral earth pressure of the soil behind it.
Conclusion: Option (d) is the only structure designed for the purpose of retaining soil.
The pipe appurtenance that releases trapped air in pipelines is:
A)
Check valve
B)
Non-return valve
C)
Sluice valve
D)
Air valve
Step-by-step reasoning:
1. Analysis of the requirement: The question asks for a pipe appurtenance specifically designed to release trapped air from a pipeline. Trapped air can cause 'air locks,' reducing the flow capacity and potentially causing water hammer or pipe bursts.
2. Evaluating Option (d) Air valve: An air valve (or air release valve) is specifically designed to automatically exhaust air that accumulates at high points in a pipeline, ensuring smooth hydraulic flow. This matches the requirement perfectly.
3. Evaluating Option (a) Check valve: A check valve is a one-way valve that allows fluid to flow in one direction and prevents backflow. It does not release air.
4. Evaluating Option (b) Non-return valve: This is another term for a check valve. Its primary function is to prevent reverse flow, not to vent air.
5. Evaluating Option (c) Sluice valve: Also known as a gate valve, it is used to completely stop or allow the flow of water (isolation valve). While it can be used to manually drain a pipe, its primary purpose is not the automatic release of trapped air.
Conclusion: The air valve is the only component listed whose primary function is the removal of trapped air.
Which process is used to remove dirt and sand from raw water?
A)
Flocculation
B)
Chlorination
C)
Sedimentation
D)
Aeration
Step-by-step reasoning:
1. The goal is to remove 'dirt and sand' (suspended solids) from raw water. These materials are typically denser than water.
2. Sedimentation is a physical water treatment process that uses gravity to allow heavy particles (like sand, grit, and silt) to settle at the bottom of a tank over a period of time, effectively removing them from the water column.
3. Evaluating other options:
- Flocculation: This is a chemical/mechanical process used to clump small particles together into larger 'flocs' so they can be settled more easily; it does not remove the particles itself but prepares them for sedimentation.
- Chlorination: This is a disinfection process used to kill bacteria and viruses; it does not remove physical dirt or sand.
- Aeration: This is the process of mixing air into water to remove dissolved gases (like CO2 or H2S) or to oxidize dissolved metals (like Iron or Manganese); it is not used for removing sand.
What is the major advantage of ERW pipes?
A)
High flexibility
B)
Corrosion resistance
C)
Smooth surface and economical
D)
Fire resistance
ERW stands for Electric Resistance Welding. These pipes are manufactured by rolling a flat strip of steel into a cylindrical shape and welding the longitudinal seam using high-frequency electric current.
1. Why 'Smooth surface and economical' is correct: Because ERW pipes are produced from cold-rolled strips, they possess a very smooth internal and external surface finish, which reduces friction loss for fluids. Furthermore, the mass-production process of ERW is significantly more cost-effective (economical) compared to seamless pipes, which require complex piercing and drawing processes.
2. Why other options are incorrect:
- High flexibility (a): Steel pipes, including ERW, are rigid. Flexibility is a characteristic of plastics (like HDPE) or rubber, not ERW steel.
- Corrosion resistance (b): Standard ERW pipes are made of carbon steel and are highly susceptible to corrosion unless they are galvanized or coated. Corrosion resistance is a property of stainless steel or PVC.
- Fire resistance (d): While steel is non-combustible, 'fire resistance' is a general property of most metals and not a specific 'major advantage' unique to the ERW manufacturing process compared to other steel pipes.
The most economical channel section for open flow is:
A)
Semi-circular
B)
Circular
C)
Rectangular
D)
Trapezoidal
In fluid mechanics, the 'most economical channel section' is defined as the cross-section that provides the maximum discharge for a given cross-sectional area, slope, and roughness. According to Manning's equation, discharge (Q) is maximized when the hydraulic radius (R = Area/Wetted Perimeter) is maximized. This occurs when the wetted perimeter (P) is minimized for a constant area (A). Among all possible geometric shapes, a circle has the smallest perimeter for a given area. For an open channel (where the top is open to the atmosphere), the shape that minimizes the wetted perimeter is a semi-circle.
Comparing the options:
1. Semi-circular: The absolute most economical section because it has the minimum wetted perimeter for a given area.
2. Rectangular: Economical only if the width is twice the depth (b = 2y), but still less efficient than a semi-circle.
3. Trapezoidal: The most economical trapezoidal section is half of a regular hexagon, which is more efficient than a rectangle but less efficient than a semi-circle.
4. Circular: A full circle is used for closed conduits (pipes), not open flow channels.
Which type of intake is commonly used in rivers?
A)
Wet intake
B)
Direct pumping intake
C)
Ground intake
D)
Infiltration intake
In water supply engineering, intake structures are designed to withdraw water from a source (like a river, lake, or reservoir) and convey it to a treatment plant.
1. **Direct Pumping Intake (Option b):** This is a common method used in rivers where pumps are installed directly at the intake structure to lift water from the riverbed or water column and pump it directly to the treatment plant. It is efficient for rivers where the water level is relatively stable or where a pumping station can be constructed on the bank.
2. **Wet Intake (Option a):** While 'wet wells' are used in pumping stations, 'wet intake' is not a standard classification for a type of river intake structure in the same way direct pumping or infiltration galleries are.
3. **Ground Intake (Option c):** This is a generic term and not a standard technical classification for river intake structures.
4. **Infiltration Intake (Option d):** Also known as infiltration galleries, these are used when the river water is highly turbid or when the riverbed consists of permeable sand/gravel. While used in rivers, they are a specialized type of intake used for pre-filtration rather than the 'common' general-purpose intake used for bulk water withdrawal.
Therefore, among the given options, direct pumping is the most common general method for river water abstraction.
Which one of the following is not a component of water treatment plant:
A)
Rapid sand filter
B)
Flocculator
C)
Transformer
D)
Sedimentation tank
A Water Treatment Plant (WTP) consists of several unit processes designed to remove contaminants from raw water to make it potable.
1. **Rapid Sand Filter (Option a):** This is a core component used for filtration to remove suspended particles and turbidity from water.
2. **Flocculator (Option b):** This is a critical component in the coagulation-flocculation process where chemicals are added and water is gently stirred to form larger 'flocs' of impurities.
3. **Sedimentation Tank (Option d):** This is a unit where water is held still to allow heavy flocs and suspended solids to settle to the bottom by gravity.
**Transformer (Option c):** A transformer is an electrical device used to increase or decrease the voltage of alternating current (AC). While a WTP may use transformers in its electrical substation to power pumps and machinery, a transformer is an electrical engineering component, not a water treatment process component. Therefore, it is not a component of the water treatment process itself.
Which parameter is not considered in the design of pumping mains?
A)
Head
B)
Flow rate
C)
Efficiency
D)
Turbidity
The design of pumping mains (the pipelines that transport fluid from a pump to its destination) focuses on hydraulic performance and mechanical requirements.
1. **Head (Option a):** This is critical. Total Dynamic Head (TDH) includes static head and friction losses. It determines the pressure the pump must generate to move the fluid through the main.
2. **Flow rate (Option b):** This is fundamental. The design flow rate (discharge) determines the diameter of the pipe to ensure velocity stays within acceptable limits to prevent excessive friction loss or water hammer.
3. **Efficiency (Option c):** Pump and system efficiency are essential for calculating power requirements, operational costs, and selecting the appropriate pump model.
4. **Turbidity (Option d):** Turbidity refers to the cloudiness or haziness of a fluid caused by individual particles. While turbidity is a critical parameter for water *treatment* and *quality* analysis, it is not a hydraulic design parameter for the sizing or pressure calculations of the pumping main itself. Unless the fluid is highly viscous or abrasive (which is a different property than turbidity), turbidity does not affect the hydraulic design of the pipe.
In a field hydrostatic test, the test pressure is typically:
A)
2.5 times working pressure
B)
1.5 times working pressure
C)
equal to the working pressure
D)
2.0 times working pressure
In pipeline engineering and hydrostatic testing, the primary objective is to ensure the structural integrity of the pipe and the tightness of the joints without causing permanent deformation or failure of the material. According to standard engineering practices (such as ASME B31.3 or various IS codes used in Public Health Engineering), the standard test pressure for a hydrostatic test is typically 1.5 times the Maximum Allowable Working Pressure (MAWP) or the design working pressure.
Step-by-step reasoning:
1. Working Pressure: The pressure at which the system is designed to operate normally.
2. Safety Factor: To ensure the pipe can handle surges or unexpected pressure spikes, it is tested at a higher pressure than the working pressure.
3. Standard Ratio: A factor of 1.5 is the industry standard for hydrostatic testing to verify strength and leak-tightness.
Why other options are incorrect:
- Option (a) 2.5 times: This is excessively high and could lead to plastic deformation or rupture of the pipe walls.
- Option (c) Equal to working pressure: This does not provide a safety margin to ensure the pipe can withstand operational fluctuations.
- Option (d) 2.0 times: While used in some specific high-pressure industrial applications, it is not the 'typical' standard for general PHED pipeline field tests.
The key reason for conducting a water supply survey is to:
A)
Increase groundwater level
B)
Assess rainfall patterns
C)
Improve road network
D)
Plan intake and reservoir location
A water supply survey is a preliminary engineering activity conducted to gather essential data for the design and implementation of a water supply system. The primary objectives include identifying available water sources (surface or groundwater), determining the topography of the land, and analyzing the population distribution. This data is critical for the strategic planning of the 'Intake' (where water is collected from the source) and the 'Reservoir' (where water is stored for distribution), ensuring that gravity can be utilized where possible and that the system is cost-effective and sustainable.
Why other options are incorrect:
- Option (a): Increasing groundwater level is a result of rainwater harvesting or groundwater recharge, not a reason for conducting a survey.
- Option (b): While rainfall patterns are studied during a survey, they are a component of the data collection process, not the 'key reason' or ultimate goal of the survey itself.
- Option (c): Improving the road network is a function of transportation or civil infrastructure planning, not water supply planning.
Aeration in water treatment plant is the process of:
A)
Removing Turbidity
B)
Remove dissolved gases (like CO2, H2S)
C)
Filtration
D)
Disinfection
Aeration is a water treatment process that involves bringing water and air into close contact to facilitate the exchange of gases.
1. Why Option (b) is correct: The primary purpose of aeration is to remove dissolved gases such as carbon dioxide (CO2) and hydrogen sulfide (H2S), which can cause taste, odor, and corrosivity issues. Additionally, aeration introduces oxygen into the water, which helps in the oxidation of dissolved metals like iron (Fe) and manganese (Mn), converting them into insoluble precipitates that can then be filtered out.
2. Why other options are incorrect:
- Option (a) Removing Turbidity: This is typically achieved through coagulation, flocculation, and sedimentation, not aeration.
- Option (c) Filtration: This is a separate physical process used to remove suspended particles and precipitates from water using a porous medium (like sand).
- Option (d) Disinfection: This is the process of killing pathogenic microorganisms, usually achieved through chlorination, UV radiation, or ozonation.
The slope of an open channel affects:
A)
Width of pipe
B)
Flow velocity
C)
Temperature
D)
Odour level
In open channel flow, the movement of water is driven primarily by gravity. The slope of the channel (bed slope) provides the gravitational force necessary to overcome the frictional resistance offered by the channel boundaries. According to Manning's Equation (V = (1/n) * R^(2/3) * S^(1/2}), the flow velocity (V) is directly proportional to the square root of the slope (S). Therefore, increasing the slope increases the flow velocity.
Why other options are incorrect:
- a. Width of pipe: The width of a pipe or channel is a geometric design parameter determined by the required discharge capacity, not by the slope itself.
- c. Temperature: Temperature is a thermodynamic property of the fluid and is not affected by the physical slope of the channel.
- d. Odour level: Odour is caused by chemical composition and biological decomposition of organic matter in the water, which is independent of the channel's slope.
What is the unit of measurement for earthwork volume?
A)
Square meters
B)
Liters
C)
Cubic meters
D)
Tons
In Civil Engineering, 'earthwork' refers to the process of moving, removing, or adding soil, sand, or rock to prepare a site for construction. Since earthwork involves calculating the space occupied by the material (Volume = Area × Depth/Height), it is measured in three dimensions.
1. Cubic meters (m³) is the standard SI unit for volume, making it the correct unit for earthwork volume.
2. Square meters (m²) is a unit of area, used for tasks like plastering or flooring, not volume.
3. Liters is a unit of volume typically used for liquids, not for bulk construction materials.
4. Tons is a unit of mass/weight, used for weighing materials, but not for measuring the geometric volume of an excavation or embankment.
What is the main purpose of maintaining a logbook in a Water Supply System?
A)
To record personal attendance
B)
To track daily weather report
C)
To record operational data and performance of system
D)
Sedimentation tank
In the context of System Maintenance for a Water Supply System, a logbook serves as the official technical record of the facility's operation.
1. Why Option (c) is correct: A logbook is essential for tracking critical operational parameters such as pump running hours, flow rates, pressure readings, chemical dosage (e.g., chlorine levels), and energy consumption. This data allows engineers to monitor the system's performance, identify trends, predict potential failures (predictive maintenance), and ensure compliance with water quality standards.
2. Why Option (a) is incorrect: Personal attendance is recorded in an attendance register or biometric system, not a technical system logbook.
3. Why Option (b) is incorrect: While weather might occasionally be noted if it affects raw water turbidity, the 'main purpose' of a system logbook is the operation of the machinery and distribution network, not meteorology.
4. Why Option (d) is incorrect: A sedimentation tank is a physical component (infrastructure) of a water treatment plant, not a purpose for maintaining a record book.
The Mizoram Water Supply (Control) Act mainly regulates:
A)
Use and supply of drinking water
B)
Construction of dams
C)
Water quality testing
D)
River water disputes
The Mizoram Water Supply (Control) Act is specifically designed to regulate the distribution, use, and supply of water intended for drinking and domestic purposes within the state. Its primary objective is to ensure that water resources are managed efficiently to provide a steady supply of potable water to the public and to prevent the wastage or unauthorized diversion of such supplies.
Why other options are incorrect:
- Option (b) Construction of dams: This typically falls under larger infrastructure laws, environmental clearances, or the Dam Safety Act.
- Option (c) Water quality testing: While quality is a component of supply, testing is usually governed by the Bureau of Indian Standards (BIS) or the Water (Prevention and Control of Pollution) Act.
- Option (d) River water disputes: These are generally handled at the Central Government level under the Inter-State River Water Disputes Act, 1956, rather than a state-level supply control act.