Kathmandu, July 4:

Tapping rainwater can be cheaper as compared to purchasing tanker-water to meet Kathmandu’s water demand during the dry season, states a survey.

Besides the piped water supply by the Kathmandu Uptayaka Khanepani Limited, the dry season water needs in Kathmandu are met by purchasing water delivered by tankers.

A survey conducted by Fulbright scholar Tyler G McMahan, with the help of NGO Forum for Urban Water and Sanitation, on cost and benefits of rainwater harvesting in Kathmandu showed harvesting rainwater would cost less than buying tanker water.

With an investment of Rs 17,000, a water storage system with a capacity of 2,000-litre can be set up, which is cheaper than the cost of the tanker water, as the system can be used for for many years after a one-time investment, says the report. It would certainly be cheaper than buying tanker-water.

Referring to the case of Shuvatara School, Sanepa, he said, with the installation of a rainwater harvesting plant with the storage capacity of 68,000 litres, the school is saving Rs 6,000 each month during the dry season. He said the cost of construction of the rain-harvesting system paid back within three years.

According to McMahan, the Association of Craft Producers in Kathmandu has installed a 300,000-litre storage system, which increased their dyeing capacity with adequate water even during the dry season.

McMahan said the harvested rainwater was not for use in the rainy season as such but for the dry season. He also said rainwater harvesting is safe as well.

The survey has concluded that the system could be economically advantageous and save water.

Prakash Amatya, executive director of the forum, said rainwater harvesting system could revive the traditional water sources. According to an estimate, if all households in Kathmandu collected rainwater, 280 million litres of water could be stored annually.