Slow sand filtration water treatment plants
Practical Action
• Impact evaluation
This consists of obtaining information regarding the application of the knowledge acquired
(IRC 1983; Waterlines 1997).
Example of a training programme on slow sand filtration
Programme of theoretical courses
Title Slow sand filter
OBJECTIVE
MATERIAL
METHOD
TIME
INTRODUCTION
DEVELOPMENT
EVALUATION
REVISION
Participants will be capable of describing the essential parts of a
filter and its function in their own words. To help them, they will be
provided with a drawing with no written information.
Whiteboard, felt pens, adhesive tape, flip charts and a drawing of a
slow filter with no written information
A talk followed by a discussion with questions and answers
An hour and a half
Explain that the operators need to know the essential elements of the
filter in order to understand why and how they must operate and
maintain the filter
1) Draw a filter step by step and explain its main parts and
their respective functions
2) Draw all the valves and explain their functions
3) Ask questions to verify whether the participants have
understood
4) Allow the participants to ask questions
1) Give the participants a drawing of the filter and ask them to
explain, in order, what happens in each part of the filter
(inlet-outlet) and why, as well as the operation of each valve.
2) Ask questions like the depth of the bed or the maximum or
minimum head of the supernatant layer of water.
Revise the parts that the participants were unsure of.
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