Books
Chow's Open-Channel Hydraulics is a reference, not a first textbook
Ven Te Chow's 1959 Open-Channel Hydraulics still defines the vocabulary of GVF, jumps, and routing. What to use it for, which parts age badly, and what to read first if you actually design channels.
Recommendation
Recommended for
- hydraulic engineers who already know uniform flow and need a reference
- readers who must interpret older papers, reports, and software manuals
- graduate open-channel or river-mechanics courses
Not recommended for
- a first undergraduate fluid-mechanics or open-channel course
- SI-only offices unwilling to convert English-unit examples
- engineers expecting a modern CFD or sediment-transport handbook
What problem this book solves
Open-channel problems in civil engineering are still classified the way Chow classified them: uniform versus gradually varied versus rapidly varied versus unsteady. Software will happily march a water-surface profile through a reach. Chow is what you open when the profile is nonsense and you need to know whether the control is downstream, whether the jump can sit where the model put it, or whether the routing method assumed a diffusion behavior the channel does not have.
Open-Channel Hydraulics (McGraw-Hill, 1959) is a landmark monograph. Chow died in 1981; there is no revised “Chow 2nd edition” that updates units, resistance formulas, and computational methods. Later reprints exist. Treat the book as a classic reference with a date stamp, not as the channel-design specification for a 2026 project.
Who it is for
Engineers and graduate students who already compute normal depth and specific energy and now need the theory of transitions, controls, and unsteady flow in a single, coherent voice. Historians of the field, in the useful sense: HEC-RAS still speaks Chow’s language. It is a poor first textbook for someone who has not yet seen a specific-energy diagram in a modern SI course.
Required background
Undergraduate fluid mechanics: continuity, energy, and momentum in control-volume form. Uniform flow (Manning or equivalent) and the Froude number as a classification, not as a slogan. Ordinary differential equations help for gradually varied flow; finite-difference thinking helps for unsteady chapters. If that background is missing, use a current open-channel textbook first (Sturm is the usual English-language recommendation; French, Chaudhry, or Henderson depending on the course).
Chapter map
Chow built the book as a taxonomy of flow, which is why it is still cited.
Basic principles. Classification of flow, energy, and momentum. This is the vocabulary. Specific energy and the hydraulic jump as a momentum balance belong here in spirit even when later chapters expand them.
Uniform flow. Resistance, conveyance, composite sections, and the practical computation of normal depth. Useful, but this is the part later textbooks and software documentation have updated most (unit systems, n-value guidance, composite-section conventions).
Gradually varied flow. The GVF differential equation, water-surface profile classification (the M1/M2/S1 family every hydraulic engineer still sketches), and methods of computation. This is the intellectual core of the book and of most 1D profile programs.
Rapidly varied flow. Transitions, controls, spillway and jump behavior treated as local phenomena that GVF cannot resolve. If your model inserts a jump, this is the chapter that tells you whether the sequent depths are even possible.
Unsteady flow. Flood wave movement and routing ideas that later became the lineage of kinematic, diffusion, and dynamic wave models. Read this to understand what a hydrologic routing method is dropping on the floor, not as a coding spec for a 2026 solver.
Best chapters
The GVF classification and the energy–momentum pairing at controls. If you can sketch the twelve profile types and name the control, you can audit a 1D model. The jump and transition material is the second best investment: software will not apologize for a drowned jump that violates sequent depth.
What to skip, depending on the goal
- First job on a drainage channel in SI units. Skip Chow as the teaching text. Learn GVF from a modern book, then return to Chow when you need the classification or a derivation.
- HEC-RAS user who can already compute profiles. Do not skip GVF theory and controls. You may skip dated resistance tables and worked examples in English units after you have converted one of them yourself, once, to see the algebra.
- Unsteady 2D flood modeler. Chow’s routing chapters are ancestry, not a substitute for the shallow-water equations as implemented in current codes. Read them for vocabulary (kinematic versus dynamic wave), then use the manual of the solver you actually run.
- Sediment, morphology, or 3D turbulence. Wrong book. Chow is clear-water hydraulics of prismatic and mildly irregular channels.
Theory quality
Exceptional for its time and still exceptional as a classification of 1D open-channel flow. Derivations are complete. The book taught a generation to stop treating the water surface as a CAD polyline. Weaknesses are the ones a 1959 monograph must have: resistance research has moved, computational methods have moved, and environmental and two-phase topics are largely absent.
Practical value
Rated moderate because the examples and unit system fight a modern office, and because design also needs a current standard (culvert manuals, road drainage guides, dam-safety procedures) that Chow does not try to be. The practical value that remains is diagnostic: when a profile, a jump, or a routing result looks wrong, Chow is still one of the fastest ways to name the failure.
Programming and computational value
Low as a programming book. High as the specification of what a 1D solver is supposed to be doing. If you write a standard-step GVF integrator, Chow tells you the physics; a numerical-methods text tells you the integration. Do not paste a language-model “RASify this reach” script in front of a regulatory model and call it hydraulics.
How it compares
- Sturm, Open Channel Hydraulics. The book I would assign as a first serious text today. SI-friendlier, computational, still theoretical enough. Then Chow for depth and history of the classification.
- Henderson, Open Channel Flow. Elegant, still loved, also dated. A peer classic rather than a replacement.
- Chaudhry, Open-Channel Flow. Stronger on computation and unsteady flow for readers who will write or closely check solvers.
- French, Open-Channel Hydraulics. More textbook pacing for US undergraduate courses.
Final recommendation
Own Chow if you practice open-channel or river hydraulics and read papers or old reports. Do not make it the first book in the stack. Learn uniform flow and GVF in a current text, keep Chow for controls, jumps, and the language your software inherited, and never treat a 1959 example’s roughness or unit system as a design input. The book is a reference with a spine, not a code.