This document, designed to serve as a training manual for technical instructors and as a field resource reference for Peace Corps volunteers, consists of nine units. Unit topics focus on: (1) water supply sources; (2) water treatment; (3) planning water distribution systems; (4) characteristics of an adequate system; (5) construction techniques; (6) operation and maintenance of a distribution and treatment system; (7) scope of disposal system projects in host communities; (8) the privy method of excreta design for a village; and (9) water carried sewage systems construction and maintenance. Each unit includes: an overview (statement summarizing significance of material to follow and points requiring special emphasis); an objective (definition of goal to be achieved); lists of tasks (steps followed to accomplish objectives), functional skills (knowledge skills needed to perform tasks), terminal performance tests; content information describing the knowledge and skills needed to perform tasks correctly; and lesson plans. (JN)