Lecturer: Ugo Moisello  

Course name: Complementi di idrologia
Course code: 502947
Degree course: Ingegneria Civile, Ingegneria per l'Ambiente e il Territorio
Disciplinary field of science: ICAR/02
L'insegnamento è caratterizzante per: Ingegneria Civile, Ingegneria per l'Ambiente e il Territorio
University credits: CFU 6
Course website: n.d.

Specific course objectives

The aim of the course is to give the student (who already has the basic concepts and tools of hydrology, generally aimed to estimating peak discharges with the simplest methods) the notions necessary to carry out the hydrological analyses required for master plans and important projects (which generally require the water availability analysis and an advanced study of floods). The necessary statistical notions are also given.

Course programme

Hydrology

• Energy exchanges between the earth and the outer space. The standard atmosphere. The atmospheric stability. The pressure distribution.
• Air masses and fronts. Winds and jet-streams. The relationship between pressure gradient and wind velocity. The general atmospheric circulation. The Hadley cell, the Ferrel cell and the polar cell. Origin and development of extratropical cyclones. The influence of orography on the atmospheric circulation. The effect of water masses. Marine currents. Monsoons.
• Regional statistical analyses of floods.
• The probable maximum precipitation (part 1).
• The probable maximum precipitation (part 2).
• Irrigation water requirements.
• Complete models of the rainfall-runoff process. The model of Dawdy and O'Donnel.
• The Clark model, the routed triangle model and the routed rectangle model. The use of dimensionless moment diagrams for choosing the model. Additional considerations on the Nash model.
• The unit hydrograph and the Snyder synthetic unit hydrograph. The Nash method for determining a synthetic unit hydrograph. The McSparran method for determining a synthetic flood hydrograph.
• The analysis of water availability.
• Run of river power plants and reservoir regulation.
• The minimum acceptable flow.
• Flood routing. De Saint Venant's equations. Simplified De Saint Venant's equations.
• The kinematic model and the parabolic model.
• The solution of the equations of De Saint Venant (short reference). Linearized models. Hydrologic river routing: the Fantoli-De Marchi method and the Muskingum method. Black-box models (short reference).

Statistics

• Multivariate probability distributions.
• The regression.
• The multivariate normal distribution. The regression in the multivariate normal distribution. The choice of the independent variables.
• Stochastic processes and Thomas-Fiering model.

Laboratories

• Determination of the peak discharge with a given return period by means of the index flood method.
• Determination of daily discharges by means of a complete model.
• Determination of hydrological relationships by means of a regression analysis.
• Determination of the peak discharge with a given return period by means of a synthetic unit hydrograph.

Course entry requirements

MATHEMATICAL ANALYSIS, GEOMETRY AND ALGEBRA,PHYSICS, RATIONAL MECHANICS, COMPUTER SCIENCE: The same requirements as for Hydrology (first level course). HYDRAULICS: Different kinds of flows: uniform, steady and unsteady. Hydrostatic pressure distribution. Continuity equation. Bernoulli's theorem. Friction formulae. Main characteristics of open channel flows. Undercritical and hypercritical flows, critical flow. Steady flow profiles. HYDROLOGY: Basic hydrological vocabulary, measurement units. Precipitations. Precipitation measurements. Rainfall depth-duration-frequency curves. The catchment. Basin losses (evapotranspiration, infiltration) and forms of water storage. Engineering methods for assessing losses. Surface runoff. Discharge measurements. The rainfall-runoff process: different types of models. Linear and stationary models. The instantaneous unit hydrograph. The linear channel and the time-area method. The linear reservor and the Nash model. STATISTICS: The concepts of random variable and probability distribution. Probability theory axioms. The return period. Main probability distributions (normal, lognormal, Gumbel's). The concepts of sample and frequency. The estimation of a probability distribution. Parameter estimation: the method of moments. Probability papers. Tests of hypotheses. Pearson's fitting test.

Course structure and teaching

Lectures (hours/year in lecture theatre): 38
Practical class (hours/year in lecture theatre): 14
Practicals / Workshops (hours/year in lecture theatre): 0

Suggested reading materials

Computer programs and lecture notes can be downloaded from the internet.

V.T. Chow, D.R. Maidment, L.W. Mays. V.T. Chow, D.R. Maidment, L.W. Mays. Mc Graw-Hill Book Company, 1988.

R.K. Linsley,M.A. Kohler , J.L.H. Paulus. . Applied Hydrology. Mc Graw-Hill Book Company, 1949.

U. Maione, U. Moisello. Elementi di statistica per l'idrologia. La Goliardica Pavese, 1993.

U. Moisello. Idrologia tecnica. La Goliardica Pavese, 2010.

Testing and exams

The exam consists of a written and an oral test. The oral test may be taken only after passing the written test, and the final mark is determined by both results. The student can also give up the oral test and use the result of only the written test for passing the exam.