DSD is implementing the Inter-Reservoirs Transfer Scheme (IRTS) project that builds a 2.8 km long water tunnel to connect Kowloon Byewash Reservoir and Lower Shing Mun Reservoir. The scheme serves dual purposes of reducing flood risk in Lai Chi Kok area and increasing the local yield. On one hand, it will substantially reduce the discharge of rainwater into the drainage system of Lai Chi Kok area; and on the other hand, the rainwater collected in Kowloon Byewash Reservoir can be diverted to Lower Shing Mun Reservoir to reduce overflow from the former reservoir and increase the yield of the latter reservoir. On its completion by around 2022, the IRTS is estimated to increase average local yield of around 3.4 mcm per annum, providing extra buffer of local fresh water resources.