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then don't read this one. Instead, read "The Big Necessity" (2008) by Rose George, which is a much breezier and exciting account of the global sanitation crisis.
If, on the other hand, you plan on reading more than one book on sanitation (if, for example, you want to/already work in the sector), then this book provides a lot more detail and case studies than George's book does and I recommend reading it next, though, as a result, it reads much more like a textbook (while George's reads like a gripping action novel). Don't get me wrong - this is an interesting and fulfilling book for someone like me, but may be a bit dry or technical for someone who is simply interested in getting inspired or interested in the field more generally.