Hydrology Basics

Definition and Scope of Hydrology

• Hydrology is the science of the properties, distribution, and effects of water on a planet's surface, in the soil and underlying rocks, and in the atmosphere.
• It is the branch of science or geology that studies the Earth's water.
• Hydrology encompasses the study of water on the Earth's surface and beneath the surface of the Earth, the occurrence and movement of water, the physical and chemical properties of water, and its relationship with the living and material components of the environment.

Importance of Hydrology

• Hydrology is important because the hydrologic cycle is essential for plants, animals, and humans to receive water.
• The hydrologic cycle moves nutrients, pathogens, and sediment in and out of aquatic ecosystems.

Engineering Hydrology

• Engineering hydrology deals with the study of water resource engineering.
• It involves the estimation of water resources, study of the components of the hydrological cycle, and study of the problems of floods and droughts and preventive actions.
• The scope of engineering hydrology includes the determination of maximum probable flood, water yield from a basin, study of groundwater development, and determination of maximum intensity of the storm.

Features of Engineering Hydrology

• Estimation of water resources.
• Study of the components of the hydrological cycle like precipitation, runoff, transpiration, and their interactions.
• Study of the problems of floods and droughts and preventive actions.

Applications of Hydrology

• Hydrology helps in determining the maximum probable flood that can occur at a particular location.
• It is essential for the design of hydraulic structures like dams and reservoirs, channels, and other flood control structures.
• Hydrology is necessary for the design of dams and municipal water supply units, river navigation, etc.