Engineering hydrology, in general, may be understood as the branch of engineering that deals with the study of water resources. It is also commonly referred to as water resources engineering.
Precisely, engineering hydrology may be defined as the multidisciplinary specialization of civil engineering that deals with the occurrence, circulation and distribution of water on Earth. It is a very important branch of civil engineering as it is necessary for the construction of various types of water resource-related infrastructures. Mostly, engineering hydrology is focused on the scientific study of the water cycle, water resources and water resource sustainability.
Engineering hydrology has been an important study for a very long time. Ever since the dawn of civilization, various hydraulic structures have been constructed by the use of hydrological tools. For example, during the Mesopotamian civilization dams were constructed for protecting the Mesopotamian towns from the flood. Numerous aqueducts were built by the Greeks and Romans. Irrigation activities were evident since the history of Chinese development. The development and advancement of engineering hydrology began in the first century( BC). Robert Elmer Horton is regarded as the “Father of Modern Engineering Hydrology”. He was an American civil engineer and soil scientist.
Engineering Hydrology and its applications are inevitable for planning and building hydraulic structures. It is important for solving the various existing water-related problems such as problems regarding the quantity of water, control and mitigation of flood, irrigation etc. Some of the importance are listed as follows:
1. It is necessary for determining the maximum probable flood(Maximum flood level) at the proposed construction site. For example, dam construction.
2. It facilitates engineers and hydrologists for establishing the relation between surface water and underground water resources.
3. It enables one to determine the flow over various hydraulic structures such as spillway, highway culvert, urban storm drainage system etc.
4. It is important for studying the on-site drainage and seepage condition before the commencement of any engineering construction.
5. The nature of variations of water flow, rainfall pattern etc can be obtained from the use of engineering hydrology applications.
6. It is necessary for determining the reservoir capacity to assure an adequate supply of water for domestic and other purposes.
APPLICATION AREAS OF ENGINEERING HYDROLOGY
The main application areas in the field of civil engineering can be listed as follows:
1. Irrigation Projects and Schemes.
2. Hydroelectric Power Generation Projects and Dam Constructions.
3. Water Supply Projects.
4. Disaster Prevention or Flood Control Projects.
SCOPE OF ENGINEERING HYDROLOGY
i. Determination of Maximum Probable Flood:
It is necessary to determine the frequency and occurrence of flood or maximum flood level before designing and building hydraulic structures such as dams, flood control structures and reservoirs.
ii. Determination of Maximum Intensity of Storm:
The determination of the maximum intensity of the storm is necessary to determine the drainage conditions at the site and to design the needed drainage systems.
iii. Determination of Water Yield of Basin:
For the design and construction of various structures such as municipal water tanks, reservoirs, inland navigation etc it is necessary to determine the yield of the basin (i.e. the occurrence, frequency and quantity of water that can be obtained from the basin.)
iv. Ground Water Development Study:
Engineering hydrology facilitates the study of groundwater and its development.