According to the UN-Habitat, the average rainfall in Kathmandu valley is around 1,600mm, which is about twice the world average. But we don’t really value the rainwater, and see how unfortunate we are, not getting sufficient amount of portable water due to overpopulation, unmanaged urbanization, lack of knowledge and advocacy. [break]
Kathmandu Upatyaka Khanepani Limited (KUKL) states that the daily water demand in Kathmandu at present is 320 million liters/day but the supply is only around 130 million liters/day. So we have to seek a better alternative to fulfill our water demand. Always depending upon the government and blaming is not going to solve the problem of water scarcity.
A series of field visits to different parts of Kathmandu to learn about rainwater harvesting system was a real eye opener to me, as I saw how we can fulfill our water demand by rainwater harvesting. I’m writing this article to share what I’ve learnt.
My first spot of study was Bhuekhel Pokhari, where the ground water table was replenished with the help of rainwater harvesting. Narendra Dongol, a rainwater harvesting technical expert, informed that the ground water recharge of this pond was possible by the collaboration of Center of Integrated Urban Development (CIUD) funded by United Nations Development Project (UNDP) and Bhuekhel Community Development Committee.
This project was carried two years ago and completed with the cost of Rs 1 million. This pond was used mainly for storage, recharge and retaining of water. But due to the lack of technical knowledge, the use of black clay as the bed layer on this pond didn’t help. In summer, the clay would crack, making it impossible to retain water and maintain its aesthetic beauty. However, the ground water recharge was successful as the water was infiltrated from the pond and successfully helped to replenish the ground water table.
My second study spot was the house of Dangol himself where he’s been practicing the rainwater harvesting since the last three years. The catchment area of the house is 110 square meters. The total water demand of the house is 1200 liters/day, out of which 700 liters of raw water is directly pumped from the recharge tube well and 500 liters from the treatment of grey water. He said that it cost him Rs 200,000 to install the rainwater harvesting system in his house.
Likewise, the community hospital in Dallu, which also has installed the rainwater harvesting system, was my final spot of study. It has a storage tank of 25-30 thousand liters of water. There is one settling tank, one recharge zone and one well to fulfill the water demand of the hospital.
After learning from each of these spots, I have realized the value of water and the potential of rainwater harvesting. Once this understanding reaches each and every individual and the community is ready to take up rainwater harvesting seriously, I’m sure that water scarcity won’t be as rampant as it is today.
It’s now time to use our knowledge practically and set example amongst friends and family and community by installing rainwater harvesting system. We know that KUKL cannot fulfill our water demand, so what are we waiting for? Rainwater harvesting system is not an alternative. It is our necessity.
The writer is a student at School of Environmental Science and Management (SchEMS), Mid Baneshwar in Kathmandu.
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