Kathmandu Valley has a daily requirement of more than 360 million liters per day. However; currently less than 50 per cent of the required supply is available from the municipal water supply. Furthermore, the groundwater level in the valley is being depleted at an alarming rate of average of 2.5 meters down annually, more than 3 times the sustainable recharge rate. As a result, it is important for the future of the valley that alternative sources of water are utilized.
The Lazimpat branch is one of the flagship buildings of Standard Chartered Bank Nepal Limited (SCBNL) which was initially built with a deep borewell as the main source for water supply. The average annual requirement of the water in the building is 1.8 million litres. To reduce their impact on the deep groundwater source, a more sustainable system was installed in July 2014, rainwater harvesting and recharge.
The rainwater harvesting system collects 397,000 litres of rainwater annually, which directly reduces their dependence of deep groundwater. The rainwater was collected in the existing reservoirs and to reap better benefits, the storage capacity of the premises was also extended. Additionally, the rainwater recharge system recharges 2.38 million litres of rainwater annually. The excess rainwater is recharged through recharge pits, once water runs over the overflow point from the tank. Surface rainwater is also collected in these recharge pits, reducing flooding risks in the premises as well.
Seeing the benefits of the system at their Lazimpat branch, another rainwater harvesting system was installed at the head-office of the bank in New Baneshwor in 2016. This system collects 1,072,027 litres of water annually, reducing their demand from the water source there.
Since the bank has been an advocate of promoting sustainable solutions, and has ripped the benefits of sustainable water solutions, when the opportunity presented itself, the bank continued to expand and improve rainwater harvesting collection system in Lazimpat. During renovation work happening at the branch, the team realized the opportunity to add to the rainwater collection by adding the catchment of the renovated part. Addition of this catchment allows the bank to collect further 297,290 litres annually, making the total annual collection to be 687,290 litres, for the branch.
The bank, for their work with rainwater harvesting has won an award as the Top FTSE Financial Institution Climate Performance Leadership Index it 2014. It continues to look for new ways to reduce its impact, including working to promote sustainable water management within the staff with several installing the systems at their own homes as well.
The best way to reduce reliance on the deep groundwater is to reduce demand, Standard Chartered is doing that. In addition, they are managing stormwater and recharging rainwater to replenish the shallow aquifer in the area. If more institutions like them can follow this path, it will go a long way toward a sustainable solution for water management in Kathmandu.
Standard Chartered Bank’s Current Positive Impact to date:
Rainwater Collected Annually: 1,759,317 Litres
Lazimpat Branch – 687,290 litres or nearly 40% of their yearly demand
Baneshwor Branch – 1,072,027 litres or nearly 30-40% of their yearly demand
Rainwater Recharged Annually: 2.38 Million Liters