Abstractions and effective rainfall are discussed, interception, infiltration, phi index, initial and constant loss, deficit and constant loss, infiltration equations, infiltration models of HHorton, Philip, Holtan, Green-Ampt, Smith-Parlange, effective rainfall estimation by NRCS curve number method, surface storage, time dependent infiltration, initial abstractions, and soil moisture accounting, infiltration measurements.

Introduces an abridged history of hydrology and provides a brief discussion of hydrologic science and engineering, hydrologic system, hydrologic processes, hydrologic modeling, hydrologic models, and hydrologic data sources.

Deals with watershed geomorphology and characteristics, including hierarchical structure of a draiange basin, morphological parameters, hypsometry, stream order, Horton’s laws, stream power, longitudinal stream profile, hydraulic geometry, drainage density, drainage pattern, lag time, and time of concentration.

Geographic information systems (GIS) are discussed encompassing data base management, geodatabase, data structure of geographic features, topologic data structure, geographic data model, type of data models, Earth datum, map projection, map scale, geoprocessing and geovisualization, delineation of drainage areas and streams, and derivation of hydrologic parameters using GIS.

Hydrologic modeling with particular focus on model calibration. Beginning with a short discussion of hydrologic models, the chapter goes on to discussing model calibration through optimization, goodness-of-fit indices, measures of model performance, optimization methods, model validation, and sensitivity analysis. The chapter is concluded with a discussion of optimization models included in HEC-HMS.

Describes channel routing, including governing equations, characteristics of flood wave movement, channel routing methods, modified Puls, Muskingum, Lag and K, and Muskingum-Cunge methods of channel routing, selection of a routing mehod, comparison of hydrologic and hyraulic methods of routing, and channel routing in HEC-HMS.

Covers erosion process, types of erosion, estimation of erosion using universal and modified universal soil loss equations, sediemnt yield and its determination, temporal distribution of sedienmnt yiled, sediemnt loads in channels, sediemnt transport, sediemnt properties, fall velocity, sediemnt transport functions, sediment routing, reservoir sedimentation, and erosion and sedimentation modeling in HEC-HMS.

Many design problems, such as urban drainage and channel sizing require only peak discharge which is often estimated by the rational method which is described by presenting the rational method equation, the rational coefficient, drainage area, characteristic time, implications of the method, modified rational method and implications, and applications.

Groundwater and baseflow covering aquifers and their properties, gaining and losing streams, governing equations for groundwater flow, baseflow separation, baseflow models, parameter estimation, exponential decay and linear reservoir model.

Deals with rainfall measurements and models, methods of rainfall measurement, types of rainfall, rainfall statistics, spatial and temporal distributions of rainfall, NRCS type curves, Huff curves, annual maxima and partial duration series, design storms, frequency analysis, intensity–duration–frequency relationships, depth-area relation, temporal distribution of design rainfall, probable maximum precipitation, gridded rainfall, and design of rain gauge network.

One of the main physically- based methods for overland flow and channel flow modeling is the kinematic wave method. Kinematic wave models, including kinemtic wave equations for channel flow and overland flow, analytical solutions, numerical solutions, distinguishing features of kinemtic wave model, and implementation of kinematic wave model in HEC-HMS are discussed.

Unit hydrograph models dealing with the representaion of a watershd as linear time invariant system, response function and convolution, unit hydrograph characteristics, unit hydrograph derivation, synthetic unit hydrographs, gamma distribution, Snyder, NRCS, and Clark unit hydrograph models, instantaneous unit hydrographs, instantaneous unit hydrograph models, parameter estimation, and application of unit hydrographs and instantaneous unit hydrographs, S-hydrographs.