What Is Hydrology Engineering?

Engineering hydrology refers to the disciplines that analyze the temporal and spatial variation of hydrological elements in river basins, provide hydrological data for the planning, design, construction, and management of water conservancy and hydropower projects and other water-related projects, and carry out hydrological calculations and forecasts. One of the branches of hydrology. The main contents include hydrological test, hydrological calculation, hydrological forecast, etc. ^[1]

The main research contents of engineering hydrology include

Due to the deterministic, geographical distribution, and statistical laws of hydrological phenomena, the research methods are divided into genetic analysis methods, geographical comprehensive methods, and

The basic environmental space for human existence is composed of the aerosphere, hydrosphere, and geosphere. Among them, air and water are only different forms of water, and they all belong to the research category of hydrology. Engineering hydrology provides a basis for human beings to understand natural laws and scientifically arrange national economic activities. Therefore, it has a wide range of applications, such as river and dam water energy utilization projects, water resources projects, highway and railway transportation projects such as river crossing or river crossing bridges, urban and industrial and mining water supply and drainage projects, water, oil, gas, etc. Energy pipeline project, adjacent river project, protection and sustainable use of river resources, etc. Engineering hydrology is applied to all stages of engineering construction.

During the planning and design phase of the project, according to the engineering design standards, hydrological analysis and calculation are needed to predict the amount of incoming water and changes in the river or river basin during the project's use period in order to determine the design scale of the project. If the regional water volume is expected to be too large, the project scale will be too large, resulting in excessive project investment. On the contrary, the scale of the project is too small, causing the building to fail to meet the expected design standards, and the application standards are reduced. At this stage, the project's environmental impact assessment and the preparation of soil and water conservation plans also require hydrological knowledge.

During the construction phase of the project, it is necessary to forecast or estimate the design flood during the construction period in order to determine the size of the cofferdam and diversion buildings. At the same time, the hydrological forecast is also used to scientifically arrange the construction progress. For example, cofferdams and diversion dikes are commonly used for bridge pier foundation construction in river environments.

Real-time hydrological forecasting is required during project operation management to improve project utilization efficiency. Hydrological flood forecasting is essential and important information for flood prevention, emergency rescue, disaster prevention and mitigation, and ensuring the safety of engineering buildings during flood season. The construction management of cross-river highways, railway bridges, etc., requires annual flood prevention preparations before floods based on hydrological forecasts and the conditions of lines and bridge equipment, and preventive measures should be taken as early as possible to avoid flood disasters on traffic lines. ^[5]

As early as 3000 BC, the Egyptians began to observe the Nile water level. From 450 to 350 BC, Plato and Aristotle of Greece proposed the theory of hydrological cycle. In 250 BC, China's Li Bing set up a stone man to measure the water level in Dujiangyan, Sichuan. Thereafter, the Eastern Han Dynasty Wang Chong discussed the concept of the water cycle in the book "On Heng" from 100 to 200 AD. In 1452, the "Rain Gauge System" was promulgated. In 1452 AD, Da Vinci of Italy used a buoy to measure the flow velocity, and through observation to demonstrate the r water cycle, some basic principles of hydrology began to take shape. This period is considered to be the budding period of hydrology.

During the period from 1600 to 1900, experimental hydrology emerged, and some hydrological test instruments were successfully manufactured, such as Pitot tube and Waldman flowmeter. The scientists discovered some hydrological principles, such as the Bernoulli equation and the Xiecai velocity formula that have been passed down to the present day. , Darcy's law, Manning formula, etc. In particular, in 1674 AD, the Frenchman P. Belott published the book "The Origin of the Fountain" in Paris, which raised people's understanding of the hydrological cycle to the height of quantitative description. The book describes his three-year rainfall observation on the Seine, and calculated that the annual runoff of the Seine in the basin above the Burgundy is only one-sixth of the precipitation. The announcement of this conclusion is considered to be modern hydrology. The beginning of science. To commemorate his contribution to hydrology, in 1974, UNESCO and the World Meteorological Organization jointly held a 300-year anniversary of hydrology in Paris. This period is called the founding period of hydrology.

From 1900 to 1950, countries gradually established regular hydrological stations and rainfall stations, and further explored the hydrological laws. The basic theories of hydrology have been greatly developed and applied to production practices. The application of hydrology has been widely developed. Due to the advancement of science and technology and the large-scale development of water conservancy, transportation, and power, it is urgent to solve many hydrological problems in the construction of the project; the growth of measured hydrological data and the development of hydrological station networks have promoted hydrological forecasting and calculation. In addition to many empirical formulas and forecasting methods, many inference formulas, rationalization formulas, and related factor forecasting methods combined with genetic analysis have also appeared, and the mechanism of the hydrological process has been discussed. Such as Sherman's convergence unit line in 1932, Holden's infiltration theory in 1940 and so on. At the same time, statistical methods have also begun to be used in hydrological calculations. This period is called the practical period of hydrology.

After the 1950s, new factors emerged in the world's hydrological sciences: first, the in-depth study of hydrological theories and the penetration of related disciplines, leading to many new methods for hydrological calculations and hydrological forecasting; The application of remote sensing, telemetry, and nuclear technology has brought hydrology into a modern era, such as automatic hydrological telemetry systems, online forecasting systems, and various hydrological models. In particular, the application of global positioning system, geographic information system, and remote sensing telemetry system technologies in hydrology has shown a broad prospect for real-time hydrological forecasting. Many new branches of hydrology, such as stochastic hydrology, urban hydrology, agricultural hydrology, forest hydrology, and environmental hydrology, have also emerged. ^[2]