16.6  Sanitary survey of springs

When a spring is chosen for a water supply, the sanitary survey should determine that the water quality is acceptable, the quantity of water available is adequate to meet the needs of the community and the spring is protected from contamination. The quantity of water available from a spring can vary significantly due to changes in groundwater storage.

Like wells, springs should have protective devices such as good fences and warning signs to discourage human and animal activities that might disturb the spring area. The spring box or storage tank and cover need to be watertight to prevent undesirable water from entering. Since most springs never stop producing water, an overflow is needed to ensure that water pressure does not build up and damage the spring box. The end of the overflow drain should have a screen to prevent the entrance of animals. Springs should have a diversion ditch located at the uphill end of the site which keeps rainwater from flowing over the spring area. A good impervious barrier, such as clay or a plastic liner, can help ensure high quality water by preventing potential contaminants from entering the collection facilities. Figure 16.4 shows what you should be looking for when you are doing a sanitary survey of a spring and Box 16.2 has a list of questions to be asked. The numbers in the diagram demonstrate particular points and correspond to the questions in the checklist.

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Figure 16.4  Sanitary inspection of a protected spring. The numbers refer to the questions in Box 16.2. (Source: as Figure 16.3)