Discharge in a Distributary Canal

In a distributary canal, the discharge refers to the volume of water flowing through the canal at a given point in time. The discharge is typically measured in cubic meters per second (cumec) and is an important parameter in hydraulic engineering.

Factors Affecting Discharge
Several factors can influence the discharge in a distributary canal, including:
- Catchment area: The size and characteristics of the catchment area directly affect the amount of water available for flow in the canal. A larger catchment area generally results in a higher discharge.
- Rainfall: The amount and intensity of rainfall in the catchment area influence the inflow of water into the canal. Higher rainfall can lead to increased discharge.
- Evaporation: The rate of evaporation from the canal surface can reduce the overall discharge.
- Upstream inflows: The presence of tributaries or other upstream water sources can contribute to the discharge in the distributary canal.
- Water demand: The amount of water being withdrawn from the canal for various purposes, such as irrigation or industrial use, can affect the discharge.

Discharge Limit in a Distributary Canal
The discharge in a distributary canal is typically limited by the capacity of the canal and the design considerations. Exceeding the maximum discharge limit can lead to flooding, erosion, and other undesirable consequences. Therefore, it is important to determine the maximum safe discharge for a distributary canal.

According to the given options, the discharge in a distributary canal generally does not exceed 30 cumec. This means that the design and capacity of the canal are typically based on a maximum expected discharge of 30 cumec. It is important to note that this value may vary depending on the specific design criteria and local conditions.

Importance of Discharge Limit
Setting a discharge limit is crucial for the safe and efficient operation of a distributary canal. By defining the maximum expected discharge, engineers can design the canal and its related structures, such as weirs, gates, and regulators, to handle the anticipated flow. This helps prevent overtopping, erosion, and other hydraulic issues that may arise from excessive discharge.

In conclusion, the discharge in a distributary canal generally does not exceed 30 cumec. This value is determined based on the design criteria, capacity of the canal, and other factors influencing the flow. By respecting the discharge limit, engineers can ensure the safe and efficient operation of the canal system.