River-bottom intake waterway

Slovak term: Slovenský termín

1. Method of collecting surface water from the bottom of a waterway (WHO et al. 2003).

Explanation

River-bottom or Tyrolean intakes for drinking-water systems are usually used in small rivers and streams where the sediment content and bed load transport are low. The water is abstracted through a screen over a canal (usually made of concrete and built into the river bed). The bars of the screen are laid in the direction of the current and sloping downwards, so that coarse material cannot enter. From the canal, water enters a sand trap and then may pass a valve and flow by gravity, or be pumped into the rest of the system.

The inlet must be checked regularly and obstructing debris removed and any damage repaired. The sand trap must be cleaned regularly. Preventive maintenance consists of painting the screens and other metal parts, such as sluices or valves. Depending on silt and bed load transport, the sand trap and screen will have to be cleaned regularly, and the screen or valve may need repairing. Any erosion undermining the structure must be repaired immediately. Every year, the concrete structure should be checked for cracks and repaired if needed. The water users may be required to help with annual cleaning and major repairs (WHO et al. 2003).

References

• WHO and IRC International Water and Sanitation Centre (2003) Linking technology choice with operation and maintenance in the context of community water supply and sanitation: A reference document for planners and project staff

Links

• WHO — The Health and Environment Lexicon