Rainwater Harvesting for Reconstruction
Practical Action
Collection Surfaces
The most common form of collection
surface is the corrugated iron roof; other
surfaces such as tiles or thatch are also
used, but are more difficult to clean and
maintain. Regular cleaning of the collection
surface can prevent biological
contamination or pollution of the rainwater
as it lands, and also reduces the workload
on any filtration devices that are fitted.
Other collection surfaces can include paved
walking areas and rock surfaces,
particularly where underground storage
facilities are used.
Guttering
Figure 2: Typical Corrugated Iron Roof, Photo:
Practical Action
In most cases, factory-made gutters are too expensive to be considered in developing scenarios
and especially in PCR contexts where local materials are preferable. Local timber can be used,
but it is likely to degrade quickly, so should only be considered as a short-term measure. More
durable is to use corrugated iron or steel sheet. A common technique is to use a clamp and two
lengths of straight timber to hold a steel or iron sheet, which can then be bent into a V-shape.
Alternatively, plastic piping can be cut in half lengthways where it is available.
It is often difficult to attach these gutters to downpipes, so they may be run straight into storage
facilities if this is the case. The figures below demonstrate the technique described and some
pictures of common gutter options.
Figure 3: Simple gutter-making process
Illustration: Martin Bounds (based on Practical
Action technical brief ‘Rainwater Harvesting’
Ahmed, S. (2008)
Figure 4: Simple gutter fixing options
Illustration: Martin Bounds (based on Practical
Action technical brief ‘Rainwater Harvesting’
Ahmed, S. (2008)
Timber
Folded steel sheet
Half plastic piping
Warwick University’s Development Technology Unit (DTU) has produced a comprehensive guide to
gutter design for RWH applications available here.
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