Lecturer: Ugo Moisello  

Course name: Idrologia LS
Course code: 064051
Degree course: Ingegneria per l'Ambiente e il Territorio, Ingegneria Civile
Disciplinary field of science: ICAR/02
The course relates to:
University credits: CFU 6
Course website: n.d.

Specific course objectives

The course is aimed to give the student (who already can solve the problem of estimating flood discharges by simple methods) the complementary knowledge, necessary for carrying out the hydrological study, requiring an accurate analysis of water availability and floods, of important projects involving water resouces.

Course programme

Lessons (the length of a lesson is two hours): hydrology
1. Energy exchanges between the Earth and the outer space. Standard athmosphere. Athmospheric stability. Athmospheric pressure distribution./ 2. Air masses and fronts. Winds and jetstreams. The relationship between pressure gradient and wind velocity. The general circulation of the athmosphere. Hadley’s cell, polar cell and Ferrel’s cell. Extratropical cyclones. The influence of orography on the athmosheric circulation. The influence of water masses. Ocean currents. Monsoons./ 3. Regional statistical analyses of floods./ 4. Probable maximum precipitation (part 1)./ 5. Probable maximum precipitation (part 2)./ 6. Irrigation water requirements./ 7. Complete models of the rainfall-runoff process. The model of Dawdy and O’Donnel. The linear perturbation model./ 8. Clark model, routed triangle and routed rectangle. The use of dimensionless moments for choosing the model. The origin of the Nash model./ 9. The concept of unit hydrograph. Synthetic unit hydrographs and synthetic instantaneous unit hydrographs. Snyder’s unit hydrograph. The Nash of British catchments. The synthetic flood model of MacSparran./ 10. The analysis of water availability./ 11. The regulation of reservoirs./ 12. The use of stochastic processes in the analysis of water availability. Thomas-Fiering model. Montecarlo method./ 13. Minimum acceptable flow./ 14. Flood routing. De Saint Venant’s equations. Simplified De Saint Venant equations./ 15. Kinematic model and parabolic model./ 16. The solution of De Saint Venant’s equations (basics). Linearized models. Lumped flood routing. Fantoli-De Marchi method, Muskingum method

Statistics (the length of a lesson is two hours): statistics
1. Joint probability distributions./ 2. Regression./ 3. The multivariate normal distribution. The regression in multivariate normal distribution. The choice of variables in multiple regression.

Laboratories (the length of a unit is two hours)
1 (2 units). Estimation of the peack discharge with an assigned return period by the index flood method./ 2 (1 unit. Use of a complete model of the rainfall-runoff process for determining mdaily mean flows./ 3 (1 unit). Determination of some hydrological relationships by means of multiple regressions (linear and logarithmic)./ 4 (2 units). Estimation of the peack discharge by means of design hyetographs and a synthetic instantaneous unit hydrograph.

Course entry requirements

MATHEMATICAL ANALYSIS, GEOMETRY AND ALGEBRA, PHYSICS, PHYSICAL MATHEMATICS, COMPUTER SCIENCE: the same entry requirements as for the course of Hydrology. HYDRAULICS: uniform, steady, unsteady motion. Hydrostatic pressure distribution.Continuity equation. Bernoulli's theorem. Friction formulae. Main characteristics of open channel flows. Under critical, critical, hypercritical flow. Steady flow profiles. HYDROLOGY: basic terminology and units of measurement. Precipitations. Precipitation measurements. Rainfall depth-area-duration relationship. The catchment. Catchment losses (evapotranspiration, infiltration) and different forms of water storage. Practical methods for estimating the catchment losses. Surface runoff. Streamflow measurements. Rainfall-runoff process. Different model types. Linear and stationary models. Instantaneous unit hydrograph. The linear channel and the kinematic model. The linear reservoir and the Nash model. STATISTICS: The concept of random variable and that of probability distribution. Axioms of probability calculus. Return period. Main probability distributions (normal, lognormal, Gumbel's). The concepts of sample and frequency. Estimation of the probability function. Parameter estimation: the method of moments. Probability charts. Tests of statistical hypotheses. Pearson's goodness-of-fit test.

Course structure and teaching

Lectures (hours/year in lecture theatre): 38
Practical class (hours/year in lecture theatre): 12
Practicals / Workshops (hours/year in lecture theatre): 0
Project work (hours/year in lecture theatre): 0

Suggested reading materials

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

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

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

U. Moisello. Idrologia tecnica. La Goliardica Pavese, 1998.

Testing and exams

Two written tests are given during the term (one at half term, the other at the end). The average of the two marks, if sufficient, can be adopted as final mark (in this case the two written tests are equivalent to the final exam). If the average mark is not sufficient, an oral exam has to be taken by the student. If only one of the two written tests is sufficient, the student can take the exam only on the subjects of the failed test, and the final mark is the average of those of the successful test and of the passed oral exam. The student can always give up the results of the written test and take an oral exam on all the subjects of the course.