The house of Suvechha Manadhar, a resident of Kupondol, Kathmandu, is connected to the municipality’s drinking water supply but it’s hardly of any use. Since her house is in the end of the alley, water doesn’t reach her tap. To solve this drinking water problem, she spent thousands of rupees and dug a well but nothing could overcome the quality factor. Investment just went to waste.
But Manadhar soon solved her problem by learning the techniques of rainwater harvesting from NGO Forum for Urban Water and Sanitation. Until 6-7 years back, people were unaware that water could be collected and used for drinking purposes as well. Suvechha now filters and drinks rainwater that tips down from her terrace. With the growing need to conserve the country’s groundwater resources, rainwater harvesting is the next best option to meet our water needs. Rainwater is free, so why not make use of it?
Once the Melamchi water supply scheme comes into effect, water in Kathmandu will be more expensive. Thus, rainwater harvesting can provide a practical alternative.
Dr Roshan Raj Shrestha, Chief Technical Advisor to UN-Habitat’s Water for Asian Cities Programme, which is popularizing environment-friendly technologies in Nepal like rainwater harvesting, says that collecting rain that falls on a roof or a sealed surface is a “simple concept that brings a lot of benefits.”
“Rainwater-harvesting is very affordable. Everybody is capable of using the technology. We just need to re-popularize it,” Dr Shrestha says of the indigenous technology which has been edged out of Nepalis’ daily lives by “modern technologies.”
UNTAPPED RESOURCE
Despite these advantages, rainwater has become an “untapped resource” due to the introduction of piped-in water systems. If one were to study the actual water supply situation versus local rainwater management, it would become obvious that rainfall is typically not regarded as a water resource; instead, it is often seen as a hindrance to certain activities such as construction. Sealed areas, roofs of buildings and roads are provided with collection systems for water run off but these systems are, most of the time, used for drainage purposes into nearby rivers and streams.
The government has recently considered rainwater collection as a complement to the city water supply. Everyone prefers a water service delivery system that reaches consumers in their homes in potable form, 24 hours a day. Rainwater harvesting can be used as a viable supplement to such a main system, depending on an individual household’s water needs.
It’s worth noting that once the Melamchi water supply scheme comes into effect, water in Kathmandu will be more expensive than it currently is. Rainwater harvesting can provide a practical alternative and can be used by those households that consume more than the monthly minimum volume.
IS EXTRACTING WATER FROM BORING THE ONLY SOLUTION?
As a result of the water scarcity, some households have already constructed deep boring plants with huge investment. According to a study, about 300 deep boring wells have been constructed by both the Kathmandu Upatyaka Khanepani Limited and the public. When the ordinary wells stop generating water, people have started buying water from tankers. To meet the demand, the tanker owners themselves have erected deep boring plants. As a result, the storage of drinking water beneath the surface is decreasing and coming up with high iron content as a chemical reaction. In addition, due to haphazard disposal of solid waste, underground water has shown content of harmful elements like nitrate and ammonia in the water of different areas of the capital.
Such lethal elements that cannot be treated domestically will later lead to fatal diseases like cancer, and water with nitrate is even more dangerous for suckling children. World Health Organization has said that drinking of nitrated water could cause respiratory problems in suckling children and could also be fatal. We can safely say that underground water of the Kathmandu valley has become more dangerous due to concentration of ammonia and nitrate.
RE-POPULARIZING THE INDIGENOUS TECHNOLOGY
We should “re-appreciate” the culture of rainwater harvesting. It has been part of our ancestors’ lives. Our great-grandparents valued rainwater for good reasons. If they practiced it for centuries, why can’t we?
The re-integration of rainwater harvesting also means the formulation and incorporation of a national policy. A national policy on rainwater harvesting is needed.
If the government succeeds in re-popularizing the indigenous technology, experts say it could save as much as Rs. 2.8 billion annually in Kathmandu valley alone besides its environmental benefits.
Interestingly, Dharan municipality encourages the general public on utilizing rainwater, thus, it has announced a policy of providing 30 percent rebate on building permit revenue for households, which has installed rainwater harvesting system. The Ministry of Physical Planning and Works in its 20 years vision document emphasizes rainwater harvesting system in every house and has made it mandatory in new government building constructions.
There is no doubt that the reintroduction and mainstreaming of rainwater harvesting at both local and national levels, through regulations and a national law, could effectively address Kathmandu’s growing water needs.
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