Producing clean water from urban sewage streams in India
Recently in India a project started for local treatment of urban sewage streams for healthy reuse (LOTUS HR). This project aims to clean one of the most polluted streams in Delhi. “India is facing its worst water crisis in a decade,” says Tanya Singh of Wageningen Environmental Research (Alterra). “Its rapid urbanization keeps on putting more stress on fresh water supply, while simultaneously water resources are polluted by untreated wastewater discharge.”
Taking measures to maintain freshwater quantity and quality may cause large rises in societal costs. The introduction of low costs and efficient technologies for wastewater treatment and water reuse is urgently needed. The LOTUS HR project will demonstrate a novel, holistic water management approach for the recovery of water, energy and nutrients from urban wastewater. An experimental testing site along the Barapullah drain, which is located in the central part of New Delhi, will be created for this purpose. It receives urban sewage and discharges it into the highly polluted Yamuna River.
This location is an ideal demonstration site for water solutions focused on water reuse. The drain is characterized by complex sewage with emerging compounds and heavy metals that is representative for many other cities. The water is anaerobic and has a significant presence of faecal coliforms, a pH 6-8 and a temperature of 26-32oC. Fluctuations in storm water over the year show significant influences on the characteristics of the water in the drain.
Tanya Singh: “We will determine the required treatment and reclamation steps by the water quality needed for safe and healthy reuse in households, industry and urban agriculture. We will incorporate innovative, but proven robust technologies in a pilot treatment plant along the Barapullah drain. The programme aims at Water Reuse Safety Plans and their socioeconomic and legal impact in combination with quantitative risk assessments of the produced water qualities. Furthermore, we will focus on pre- and post-treatment of wastewater from the Barapullah drain to make it available for safe reuse. We will pay special attention to pathogen removal and conventional and emerging pollutants removal.”
The project is an Indian-Dutch partnership, amongst others supported by Minister Bert Koenders. He attended the official start of the project and said on this occasion: “The Barapullah project is a perfect example of the Indian-Dutch cooperation on innovation, to solve societal challenges. This project is unique, as researchers will work with companies to develop new technologies to clean waste water in an innovative and affordable manner to be reused for agriculture, industry and households.”
The final goal of the programme is to demonstrate that producing water, nutrients and energy is possible from the Barapullah drain wastewater. In this way, it will turn the drain into a profitable ‘mine’ that produces clean water for households, irrigation and industry, as well as energy by anaerobic treatment of the organic fraction of the drain, and nutrients for (urban) agriculture. Meanwhile it will lead to a reduction of the ‘expensive’ drinking water use and is a show case on how to reduce the poisoning of the Yamuna river. This leads to the development of reliable technologies for water reuse in other Indian mega cities.
Tanya Singh: “The local population is also participating in the project. This will ensure that the demonstration site becomes a self-sustaining initiative that will not finish at the end of the project and will be taken up by the end-users.”