Kathmandu Metropolitan City has adopted rainwater harvesting and groundwater recharge system as part of a water replenishing tool to ensure sufficient water supply in the capital city.

Speaking at a webinar on 'Issues, Challenges and Way Forward for Rainwater Harvesting' organised today, Jayashree Rajbhandari, an expert at KMC Urban Planning Commission, informed that the metropolis came up with the rainwater harvesting and groundwater recharge campaign to meet the water demand through the traditional sources like stone spouts, well and groundwater.

"Currently, the demand for water in Kathmandu is around 450 million litres per day. Even if Melamchi Water Supply Project distributes 170 million litres on a daily basis, there will be a shortfall of nearly 280 million litres. There is a need to opt for alternative sources to bridge the gap between demand and supply," Rajbhandari said. Groundwater recharge is a hydrologic process in which water moves downward from surface water to groundwater.

Similarly, KMC will be installing rainwater harvesting system in communities as per necessity to meet the growing water demands.

Water being supplied by Kathmandu Upatyaka Khanepani Limited accounts for nearly 50 per cent of groundwater, which is extracted through deep boring. It is also contributing to depletion of water level in Kathmandu. The campaign aims to raise level of groundwater of the capital city.

The groundwater level of the city is depleting and needs to be recharged.

Groundwater recharge is a process in which water moves downward from earth's surface to groundwater.

Gongabu-Ranibari Groundwater Recharge Project has already been completed. Rehabilitation of the pond in Bhuinkhel, Swoyanbhu, is over. Recovery work of Kamalpokhari, a historical pond, is underway. KMC has also started conservation of Hiti Pokhari and Nagpokhari. Rainwater will be harvested in the ponds. Priority has also be accorded to hotels, hospitals, schools and apartment buildings for rainwater harvesting.

Shekhar Raghavan from Tamilnadu-based Rain Centre said that rainwater harvesting was a process of collecting and utilising the rain that falls on rooftops and other surfaces for short-term and long-term use. "The fresh rainwater harvested during two-three months could be used to meet the water demand for remaining months of a year," he said.

Anisha Karna from Smart Pani highlighted that the rainwater collected in wet season could be utilised in dry season to meet the water demand. Engineer Kishor Thapa, a former secretary, suggested that the use of ponds, lakes, check dams, deep well and porous pipes were some of the measures to groundwater recharge.

A version of this article appears in the print on July 24 2021, of The Himalayan Times.