Project: sc090025/R1

 

4%
74%

2%
20%
Figure 2.1: Thames Water ‘Life Cycle Costs Model’ 
Contribution 
to whole life 
costs (%) 
1 Acquisition costs 
4 
2 Basic energy costs 
74 
3 Additional energy 
costs 
2 
4 Maintenance costs 
20 

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5 
This report primarily aims to help the engineer to be independently capable of defining his/her 
system, to ensure the most efficient pump is selected for a particular application. However, the 
report also aims to impart sufficient understanding and depth of knowledge to allow the 
engineer to think beyond the textbook, to the possibility of encountering unusual circumstances 
in a particular pumping scheme where normal practices do not apply. 

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3. Pumping station fundamentals 
3.1 Pump selection 
Pump selection is largely driven by the requirements of the application in question (Terry 1995)
.
The different types of pump fall into two main categories. Low flow and high head pumps are 
generally used for transfer of water over long distances or up large height differences and are 
commonly found in sewer networks, whereas high flow and low head pumps tend to be used on 
flood defence and are the main focus of this guidance.
Of the pumps encountered in flood defence there are four main designs. These are: 
•
Archimedean screw pumps; 
•
axial flow rotodynamic pumps;
•
mixed flow rotodynamic pumps; 
•
centrifugal (radial) flow rotodynamic pumps. 
Figure 3.1 shows typical operating ranges for the different pump types. As can be seen, the 
typical operating ranges of flood defence applications can be serviced by axial flow or mixed 
flow type pumps. In practice, there will be overlaps between manufacturers’ ranges of pump 
types.