This survey and assessment project was prepared for a client operating a hospital facility in rural Bihar, an Indian state south of the eastern half of Nepal which is known for its poverty and poor education level.
The major issue with the campus water resources was the high levels of iron content in the water supply. Though not a health hazard, the high iron content of the main deep well made water use problematic for the numerous residents of the campus, forcing them to rely on unprotected and contaminated shallow wells for water supply. After investigating the situation, the eMi² team discovered that the shallow wells also had high levels of iron content, but because of the method of use, the water appearance was of greater clarity than from the main well and central tank. The team built awareness of some of the key concepts for the treatment of water with high iron content:
1. Keeping the iron sediment undisturbed
Iron sediment will naturally settle out of water and will collect at the bottom of the tank or vessel the water is in. If the outlet pipe is located near the bottom of the tank, this iron sediment will be drawn out with the water flow. This was why the main tank water was discolored and the shallow well water, though also containing iron content, was clear. When the main tank was emptied completely, water refilling the tank disturbed the iron sediment, thoroughly mixing it back into the new water, producing a very reddish / tea colored appearance.
2. Water rest time for iron sedimentation
Simple water sample tests showed and campus staff knew that iron sediment will naturally settle out by giving the water rest time. Simple visual tests showed to everyone that deep well water ‘clarified’ significantly in less than 12 hours of rest.
3. Chlorine chemical treatment
Dosed chlorine in the water will cause a greater, more complete sedimentation of iron than is possible through natural resting, and causes it to happen with less rest time. A proper dosing of chlorine will also have the side benefit of killing bacteria contaminants which may occur in the water source or in the piping network.
To help the client take immediate steps to improve the quality of water and to eliminate their reliance on the shallow, contaminated wells, a low cost remediation program was developed which implements the three key treatment concepts above. This program will be the first step toward and will build interest in a longer-term solution for iron treatment. The remediation program plan is a series of work notes with key illustrations that covers the first 9 steps which target the critical areas for water supply and utilize the infrastructure assets which are already in place.