New Delhi, May 26 : The National Mission for Clean Ganga (NMCG) on Wednesday signed two quadripartite agreements for development of sewage infrastructure, including a 35 million litres per day (MLD) Sewage Treatment Plant (STP) for Maheshtala situated on the east bank of Ganga in West Bengal. The agreement for the STP is signed under Hybrid Annuity Mode at a total cost of Rs 273.52 crore. One agreement is an Escrow Agreement between NMCG, Kolkata Metropolitan Development Authority (KMDA), M/s Maheshtala Waste Water Management Private Limited (MWWMPL) and Union Bank of India while the other agreement is a Substitution Agreement between NMCG, KMDA, MWWMPL and Oesterreichische Entwicklungsbank (Development Bank of Austria), a statement from the Ministry of Jal Shakti said. This project aims to stop the flow of sewage into River Ganga from the town. The major components of the project include a 35 MLD STP, four pumping stations, six diversion structures, Repair & Rehabilitation work and 15 years' Operation and Maintenance (O&M) etc. The project under Hybrid Annuity Mode (HAM) would mean 40 per cent of construction cost will be paid during 24-months construction period and balance 60 per cent will be paid as quarterly annuities along with interest and O&M cost over a period of 15 years. Oesterreichische Entwicklungsbank AG (Development Bank of Austria) is financing MWWMPL, which will be responsible for the entire development and operation of both sewerage network and STPs for 15 years of the concession period. The payment during the operations period will be subject to achievement of Key Performance Indicators (KPIs) in terms of treated waste water quality for the STPs, the statement said. /IANS