Book excerpt: Lumpy Water Math was written to help wastewater treatment plant operators and collection system operators with the basic problem solving ability needed to evaluate and control these systems. This understanding will help the operator use math in day-to day operation as well as help prepare for certification exams. The math will be helpful to water supply and distribution system operators as the math used is basically the same.The instruction begins with basic instruction in solving for areas and volumes, detention time, flow calculations, hydraulic and organic loading and progresses to specialty areas such as activated sludge and laboratory calculations. The book includes tips for making problem solving and use of calculators easier. Typical state design standards are listed so that problem answers can be compared to accepted values. The book includes many practice problems with answers given in the appendix to help operators become proficient in basic problem solving.