Lecturer: Fulvio Bollini   Ugo Moisello  

Course name: Hydrology and Watershed Hydraulic Management
Course code: 502561
Degree course: Ingegneria Civile
Disciplinary field of science: ICAR/02
L'insegnamento è caratterizzante per: Ingegneria Civile
University credits: ECTS 12
Course website: n.d.

Specific course objectives

Module 1 (Hydrology) gives the notions necessary for solving the hydrological problems most commonly met with in the engineering practice: analysis of water availability and analysis of floods. The module also gives the elements of statistics necessary for designing waterworks in accordance with the chosen risk level. Module 2 (Watershed Hydraulic Management) gives the basic elements for land protection, conservation and reclamation, and for a correct, environmental friendly land utilization.

Course programme

Module 1 (Hydrology) coincides with the 6-credit course of Hydrology, module 2 (Watershed Hydraulic Management) with the 6-credit course of Watershed Hydraulic Management.

Module 1 (Hydrology)
Lectures (40 hours)

• Introduction. Origin and classification of precipitation. Thunderstorms, hurricanes. The factors of the rainfall regime. The rainfall regimes in Italy.
• Rain gauges. Tables of the Italian Hydrographic Service with rainfall observations. Computation of the rainfall volume over an area (with different methods).
• Random variables, probability and axioms, non exeedance probability and probability density.
• The hydrographic basin: definition and principal characteristics. Different types of runoff. Determination of the concentration time.
• Probability distribution parameters, moments. Variables which are functions of random variables. Return period. Binomial distribution.
• Basin losses and different forms of water storage. Depression storage (short description). Dalton's law. Evaporation factors and steady evaporation. Evaporimeters (short description). Different evaporation types (short description). Actual and potential evapotranspiration. Infiltration (short description).
• The normal distribution and other continuous variable distributions.
• The practical determination of basin losses.
• The inference problem. Frequency, sample moments. Estimation of a probability distribution. Probability papers. Parameter estimation. Method of moments.
• River stage and discharge. Staff gauges and continuous water-level recorders. Current meters. Discharge computation. Stage-discharge relations.
• Statistical tests. Pearson's test of fit.
• The runoff regimes in Italy. Tables of the Italian Hydrographic Service with staff-gauge readings. The flood hydrograph analysis.
• Statistical analyses of floods: classification. At-site analyses. The relation between the annual maxima of peak and mean daily discharge. The probability distribution of the N-year maximum discharge.
• Dependence of rainfall depth on duration and area.
• Design hyetographs.
• The rainfall-runoff process. Mathematical models and relations. The rational method. White-box and black-box models. The determination of the net rainfall and of the stormwater runoff.
• Linear and stationary systems. The instantaneous unit hydrograph and its application to stormwater runoff models. Discretization of the instantaneous unit hydrograph.
• Series and parallel connections of linear stationary models. The linear channel and the time-area model. The linear reservoir and the sewerage network model constituted by a linear reservoir. The Nash model.
• The model determination: choosing model type and estimating parameters. The least squares method and the method of moments.
• Presentation and comment of slides showing measuring instruments and methods.

Module 1 (Hydrology)
Laboratories (12 hours)

• Lab. n. 1. The determination of the peak discharge with an assigned return period by means of Gumbel's law.
• Lab. n. 2 (part 1, in computer room). The determination of the peak discharge with an assigned return period with different probability distributions and the determination of the probability distribution of the N-year maximum (use of program MASSIMI).
• Lab. n. 2 (part 2). The determination of the peak discharge with an assigned return period: choice of the distribution and determination of the probability distribution of the N-year maximum (analysis and utilization of the computer program output).
• Lab. n. 3. Determination of a rainfall depth-duration-frequency curve.
• Lab. n. 4 (in computer room). The determination of a rainfall depth-duration-frequency curve and of some design hyetographs (use of program PIOGGIA).
• Lab. n. 5 (in computer room). Determination of the instantaneous unit hydrograph of a white-box model (use of program IUH) and flood hydrograph computation.

Module 2 (Watershed Hydraulic Management)
Lectures (36 hours)

• Water in the soil (7 hours). Soil physical and mechanical characteristics . Occurrence, nature and movement of water in soil: moisture, capillarity, infiltration, percolation, ground water flow. Hydraulics of wells .
• Land and soil drainage (6 hours) The effects of water excess on surface and in soil profile. Ground water drainage: horizontal pipes system, deep wells system: criteria and methods for planning and design. Subsurface and surface drainage systems.
• Land reclamation (9 hours.) The problem and the proposed solutions during the centuries. Estimation of design discharge for the channel network: statistical analysis of measured discharges, rainfall-discharge relationships and models. The drainage network: hydraulic design of stable channel section, and associated structures. Pumps ad pumping stations. Peak discharge reduction through storage.
• Soil erosion (5 hours). Physical processes, space and time scaling of the phenomenon. Modeling the erosion: the universal soil loss equation (U.S.L.E.), physically based models. Prevention and remediation: control methods and strategies.
• Mountain basin training and restoration (9 hours). Physical processes in natural channels (sediment transport, erosion, deposition) and on the slopes (surface erosion and mass movement). Criteria for the control of grading/degrading in the stream network and for the control of bank erosion: design of sills for bed fixation, revetments of bed and banks, sills and storage area for sediment control in alluvional fans. Monitoring and restoration of slopes: surface runoff control, deep and subsurface drainage for control and prevention of landslips and landslides, recovering of the green and wood cover.

Module 2 (Watershed Hydraulic Management)
Laboratories (18 hours)

• Lab. n. 1 (5 hours). Design of vertical groundwater drainage system: number and position of wells, pumps discharge and power. Design of horizontal groundwater drainage system: layout of the draining module, pipes spacing, diameter of drains and collector.
• Lab. n. 2 (5 hours). Design of the main channel of a reclamation network: computation of the critical design discharge, sizing of a stable channel section.
• Lab. n. 3 (4 hours). Design of a peak discharge reduction reservoir.
• Lab. n. 4 (4 hours). Hydraulic and structural design of a sills system for bed fixation.

Course entry requirements

Entry requirements for module 1 (Hydrology). MATHEMATICAL ANALYSIS: Concepts of function, limit, derivative, integral. Factorials, combinations. Concept of differential equation (particularly of linear constant coefficient differential equation). Concepts of multivariable function, partial derivative and partial derivative equation. Determination of the (unconditional) maximum of a one-variable and multivariable function. Computational skills: computation of simple derivatives and integrals and use of mathematical tables of limits, derivatives, integrals and definite integrals. GEOMETRY AND ALGEBRA: Basic elements of trigonometry. Elementary analytical geometry (in two- and three-dimension space). Concepts of linear and non-linear scale. Matrices and linear algebraic equation systems. Computational skills: elementary applications of trigonometry and geometry (computation of areas included). Graphic representation of functions, with both linear and non-linear (particularly logarithmic) scales. PHYSICS: Measurement of physical magnitudes and units of measurement. Basic concepts on the states of aggregation of matter and on the physical properties of bodies (density, viscosity, capillary action). Basic concepts of thermodynamics: heat exchange, specific heat,heat of vaporization, heat of fusion, vapour tension, partial vapour pression. Principles of thermodynamics. Principle of conservation of mass and principle of conservation of energy. MATHEMATICAL PHYSICS: Scalars and vectors. Sum and difference of two vectors. Vector decomposition in plane and space. Scalar product and vector product. Vector nature of forces. moment of a force about a point and an axis. Composition of forces. Moments (of different orders) of an area. Centre of gravity and moment of inertia. Cardinal equations of statics and dynamics. COMPUTER SCIENCE: Preparing and modifying a file. Working with an executable program. Entry requirements for module 2 (Watershed Hydraulic Management) The same requirements as for module one and all the arguments in the course programme of module one

Course structure and teaching

Lectures (hours/year in lecture theatre): 76
Practical class (hours/year in lecture theatre): 30
Practicals / Workshops (hours/year in lecture theatre): 0

Suggested reading materials

The computer programs, the transparencies used for the lessons and the notes relevant to lectures and laboratories can be found in internet and downloaded, for both modules, from the sites of the two 6-credit courses coinciding, respectively, with module 1 and module 2

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

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

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

Moisello, U. Idrologia tecnica. Pavia, Medea, 2014 (Archimede 3).

V.Ferro. La sistemazione dei bacini idrografici. Mc Graw Hill -2002.

AA.VV. Drainage Principles and Applications . Edited by ILRI, Wageningen, The Netherland, 1983.

G. Supino. Le reti idrauliche. Patron Bologna, 1965.

L.K.Smedema, D.W. Rycroft. Land Planning and Design of Agricultural Drainage Systems. Batsford London, 1983.

Testing and exams

The exam is composed, in principle, of an oral test on the subjects of both module 1 and module 2. The oral test on the subjects of module 1 (Hydrology) can be taken unconditionally; that on the subjects of module 2 (***) can be taken only if a written test on the same subjects has been passed (in the same scheduled exam). The student can replace the oral test relevant to the subjects of module 1 with the result of a written test taken in February. In this case, however, the mark relevant to module 1 can not be higher than 27/30, even if that of the written test is higher; moreover, the student must pass the test relevant to module 2 within the next month of September. The part of the exam corresponding to module 2 (***) is composed of an oral test. However, if the written test is passed, the student can make use (in the same scheduled exam) of that result, avoiding the oral test relevant to module 2. In this case, however, the mark relevant to module 2 can not be higher than 27/30, even if the corresponding written test mark is higher. When the student makes use of the results of two written tests, or of those of a written test (for module 1)and of an oral one (for module 2), the final mark is the average of the marks relevant to the two parts. Otherwise the final mark is that decided by the commission, based on the results of the oral test on the subjects of both modules.