This book is derived from chapter 5.1 of the main book “Dredging Technology Book1: The Basics”. In order to keep track of things section numbers and formula numbers are kept the same as in book 1. The centrifugal pump and its drive react to changes in the resistance to the flow:
1)  Blocking the flow causes the pump pressure to rise, however at the same time the drive uses less fuel and delivers less power and starts to rotate faster. 
Generating the high pressure apparently is not a problem for the drive. 
2)  Increasing the flow by reducing the hydraulic resistance causes a higher  fuel consumption  and a slower rotation speed.
Generating the lower pressure is apparently a problem for the drive.
In this book the how and why of the working of a centrifugal dredge pump with a diesel drive or electric drive is explained in detail.  
Following subjects are described:
   - Changing impeller diameter adapt to a change pipeline length .
   - Situation at the suction side of the pump.
   - The “cavitation” phenomenon. 
   - The working of the diesel engine  and electric engine.
   - Influence Engine characteristic on Pump characteristic.