The Delhi Jal Board (DJB) has initiated a new project to closely monitor water quality in the Yamuna River at Kalindi Kunj, where frothing issues at the Okhla barrage have once again become a topic of political debate. As Chhath Puja approaches, DJB officials have set up a temporary water-testing laboratory to assess water quality and share its findings with the public. This laboratory was established following a directive from a meeting led by the Chief Secretary in September, with the aim of providing real-time updates on various water quality parameters.

This laboratory evaluates water quality upstream and downstream of the Okhla barrage by taking samples and measuring key parameters, including Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), ammoniacal nitrogen, chlorides, and pH levels, among others. These metrics help assess water health and the impact of pollutants, essential information for planning interventions to address pollution in the Yamuna.

As part of efforts to minimize foam formation, the DJB has installed large tanks filled with silicone dioxide-based anti-foaming solutions in the Kalindi Kunj area. These solutions are formulated with a poly-oxypropylene group, with doses adjusted based on surfactant levels in upstream water. According to an official, approximately 1.2 tonnes of this solution has already been sprinkled, and it is anticipated that 12-15 tonnes will be required this year to tackle the persistent frothing issue. This is the third consecutive year that anti-foaming agents have been applied in the area to reduce froth levels.

Foam in the Yamuna is mainly caused by the fall of water from a height and its subsequent churning at the Okhla barrage, which agitates pollutants and surfactants in the water. DJB officials explored engineering changes to make the slope of the river gentler, hoping to reduce frothing naturally. However, the Uttar Pradesh irrigation department, which manages the barrage, found such changes unfeasible due to the barrage's structural design, which was built according to specific hydraulic criteria.

To address the frothing problem, the DJB has implemented a multi-pronged strategy. First, fabricated foam arresters are used to filter water and reduce froth. Second, static sprinklers are stationed across the barrage to target foam in specific areas, while mobile sprinklers on boats are used to treat larger patches of froth. These efforts are aimed at controlling foam formation across different sections of the river. For example, officials report that the TSS (Total Suspended Solids) levels currently stand at 250 units, pH at 7.5, and ammonia levels at 29, indicating significant pollution and contributing factors to the froth formation.

The frothing issue is being addressed by a team of eight stakeholders: Delhi’s irrigation and flood control department, Delhi Jal Board, Uttar Pradesh irrigation department, pollution control boards of both Uttar Pradesh and Haryana, the Delhi Development Authority (DDA), Municipal Corporation of Delhi (MCD), and independent experts. This collaboration aims to tackle frothing issues on a large scale, reflecting the complex challenges posed by pollution in the Yamuna River.

According to a DJB official, the froth results from “soap-like surfactant molecules” in the water, which cause bubbles when churned by the flow of water at the barrage. These molecules often come from untreated sewage containing detergents and industrial effluents, as well as the decay of water hyacinth weeds in the river, which adds to the pollutant load. Similar toxic frothing issues have been reported in other Indian cities like Bengaluru and Hyderabad, where polluted lakes have faced similar problems. This widespread issue highlights the urgent need for effective water treatment solutions and pollution controls to prevent frothing and protect water bodies.

Overall, the DJB’s efforts underscore the importance of real-time monitoring and proactive intervention to address Yamuna’s pollution issues, especially as religious festivals like Chhath Puja approach, drawing public attention to the river’s condition. The findings from the laboratory are expected to inform future strategies for reducing pollution levels and maintaining better water quality, thus helping safeguard one of Delhi’s critical water resources.

(Input from various sources)

(Rehash/Yash Kamble/MSM)