Kullu: Himachal Pradesh govt has informed National Green Tribunal (NGT) that around 11.6 million litres per day (MLD) of effluent flows from Sirmaur district in Himachal Pradesh into neighbouring Haryana with domestic sewage and not industrial pollution as the primary contributor.A revised action plan for tackling pollution in the Markanda river system, submitted by Sirmaur deputy commissioner Priyanka Verma on behalf of the state chief secretary, identifies wastewater from commercial establishments in Kala Amb’s Jattanwala Nallah along with untreated domestic sewage as the main sources of pollution, attributing the problem to incomplete sewer connectivity and inadequate arrangements for intercepting and treating wastewater.According to the plan report, Jattanwala Nallah carries an estimated 5.6 MLD of wastewater at its exit point in Himachal Pradesh. The drain receives discharge from residential areas, roadside eateries, hotels and other commercial establishments, besides some industrial effluent. Monitoring results, particularly elevated faecal coliform levels, indicate that untreated domestic sewage constitutes the predominant component of the pollution load in the drain, states the report.The state said around 85% of sewer connectivity in Kala Amb had been completed, but work on the remaining connections was still underway. In one identified area, only 55 of 443 proposed household connections had been released in Kala Amb, with the remaining work targeted for completion by December 31, 2026.A dispute over operation and maintenance costs has also held up the connection of domestic sewage to the treatment system. The district administration said funds had been sought through communications issued in 2023 and May 2026. A stakeholder meeting was held on May 16 to discuss cost-sharing and operational arrangements.The Kala Amb sewage treatment plant has a capacity of 1.7 MLD. The Jal Shakti Vibhag has been tasked with completing sewer connectivity, intercepting wastewater entering Jattanwala Nallah and diverting it to the treatment system by Dec 31, states the report.The report maintains that industrial units made a limited contribution to Jattanwala drain’s pollution load and that no major untreated industrial discharge had been observed.According to the report, the industrial contribution to the pollution load in Jattanwala drain is limited and only Ruchira Papers, which falls under the category of highly polluting industries, discharges treated water as per the prescribed limit.The unit generates around 8 MLD of wastewater, recycles approximately 4 MLD and discharges about 4 MLD after treatment. The unit has consent to discharge up to 4 MLD of treated effluent, which the report says is monitored online and complies with prescribed standards.The report also identifies solid and plastic waste dumped along the drain as a source of obstruction, stagnation and secondary pollution. Waste collection centres have been installed at identified locations, while door-to-door collection and transportation arrangements have been initiated, states the report.Efforts to restore phytoremediation measures along the drain have faced resistance from local residents, who claim possession of the land as common land. Following a joint inspection in July, the authorities recommended involving panchayat representatives and revenue officials to resolve the dispute and identify suitable sites.In its May order, the tribunal found that the earlier plan did not specify the number of drains and discharge points or provide clear commencement and completion dates.It may be mentioned that a letter petition was filed in 2022 by Dharamvir, a resident of Naraingarh in Ambala district of Haryana, stating that industrial units located in Kala Amb in Sirmaur district have been discharging polluted water into the Markanda river.The petition had stated that the Markanda is regarded as a holy river and the industrial units of Kala Amb are not only polluting her, but also causing serious diseases among the villagers and cattle of the area downstream.Markanda originates in Jogiban village in Nahan tehsil in Himachal Pradesh and flows for approximately 22 km before entering Haryana near Ogli in Kala Amb and continues its stretch in the state for another 125 km.