**Executive Summary**
This document presents the Minister of Jal Shakti's response to Starred Question No. *80 in Lok Sabha, answered on December 4, 2025, concerning the ecological health assessment of the Thamirabarani River. The statement addresses the water quality, ecological health, flow sustainability, funds allocated, challenges related to declining flow patterns, and steps taken to strengthen rejuvenation measures. A comprehensive statement addressing parts (a) to (d) of the question is laid on the Table of the House.
**Key Points / Main Content**
* **Responsibility for River Health:**
* Cleaning and rejuvenation of rivers are a continuous process.
* States/Union Territories and local bodies are primarily responsible for treating sewage and industrial effluents before discharge.
* **Water Quality Assessment:**
* The Central Pollution Control Board (CPCB) reported Biochemical Oxygen Demand (BOD) levels ranging from 4.0 mg/L to 6.2 mg/L in 2022 & 2023, placing the Thamirabarani River under Priority-IV category.
* Based on 2024 sampling, BOD levels ranged from 2.0mg/L to 3.1mg/L, indicating improvement in water quality.
* **Fund Allocation and Projects:**
* Under the National River Conservation Plan (NRCP), a 24.20 MLD Sewage Treatment Plant (STP) was set up in Tirunelveli between 2001-2007 with a cost of Rs 54.93 crore for pollution abatement.
* Atal Bhujal Yojana is not implemented in the Thamirabarani river basin.
* Groundwater recharge works have been undertaken by the State Government under MGNREGS. Funds under JJM are not maintained Basin wise.
* **River Flow and Monitoring:**
* The annual run-off depends on rainfall pattern and climatic conditions.
* The annual average run-off at Murappanadu site is 22 Million Cubic Metres (MCM) for the period 2014-15 to 2024-25.
* Central Water Commission monitors hydrological parameters through three observatories.
* Tirunelveli Municipal Corporation has formulated proposals for STPs, Solid Waste Management, Biological Parks, etc.
* **Regulatory Oversight:**
* River Rejuvenation work is monitored through a State-level River Rejuvenation Committee.
* Central Pollution Control Boards/SPCB/Pollution Control Committees monitor river water quality and industries to ensure compliance with environmental laws.
**Impact Analysis**
**Key Stakeholders: States/Union Territories (UTs) and Local Bodies**
* **Impact:** Bear the primary responsibility for cleaning and rejuvenating rivers, ensuring proper treatment of sewage and industrial effluents to meet prescribed norms before discharge.
* **Action Required:** Implement effective sewage and industrial effluent treatment processes to maintain and improve river water quality.
**Key Stakeholders: Central Pollution Control Board (CPCB)**
* **Impact:** Responsible for monitoring river water quality through the National Water Monitoring Program (NWMP), including monitoring BOD levels.
* **Action Required:** Continue to monitor river water quality and compliance with environmental regulations.
**Key Stakeholders: Tirunelveli Municipal Corporation and Tamil Nadu Government**
* **Impact:** Formulated proposals for STPs, solid waste management, biological parks etc.
* **Action Required:** Implement approved proposals and monitor river rejuvenation efforts through the River Rejuvenation Committee at the State level.
**Key Stakeholders: Central Water Commission**
* **Impact:** Monitoring annual run off of Thamirabarani River.
* **Action Required:** Continue to monitor hydrological parameters of the river through three Hydrological Observatories.
Key Entities Referenced
Ministry of Jal Shakti: The ministry responsible for water resources, river development, and Ganga rejuvenation in India, and the primary responder in this parliamentary question.
Thamirabarani River: The specific river in Tamil Nadu whose ecological health and water quality are the subject of the parliamentary question.
Tirunelveli: The district in Tamil Nadu through which the Thamirabarani River flows and where water quality assessments were conducted.
National River Conservation Plan (NRCP): A central government program under which funds were allocated for river conservation, including a Sewage Treatment Plant (STP) in Tirunelveli.
Central Pollution Control Board (CPCB): The agency responsible for monitoring water quality and reporting on polluted river stretches, as mentioned in the response regarding the Thamirabarani River.
GOVERNMENT OF INDIA
MINISTRY OF JAL SHAKTI
DEPARTMENT OF WATER RESOURCES, RIVER DEVELOPMENT & GANGA REJUVENATION
LOK SABHA
STARRED QUESTION NO. *80
ANSWERED ON 04.12.2025
ECOLOGICAL HEALTH ASSESSMENT OF THAMIRABARANI RIVER
*80. SHRI ROBERT BRUCE C:
Will the Minister of JAL SHAKTI be pleased to state:
(a) whether the Government has undertaken any recent assessment of the water quality, ecological health and
flow sustainability of Thamirabarani river in Tamil Nadu, particularly in its stretch passing through
Tirunelveli district and if so, the details thereof;
(b) the details of Central funds sanctioned, released and utilised under programmes such as the National
River Conservation Plan (NRCP), Jal Jeevan Mission (JJM) and Atal Bhujal Yojana (ABY) for river
conservation, pollution control and groundwater recharge initiatives connected with Thamirabarani basin
during the last five years;
(c) whether the Government has taken note of challenges related to declining flow patterns affecting the river
and dependent communities in southern Tamil Nadu and if so, the details thereof; and
(d) the steps being taken by the Government to strengthen river rejuvenation measures, ensure strict
enforcement of pollution-control norms and enhance Central monitoring of ecological and hydrological
parameters of the Thamirabarani river?
ANSWER
THE MINISTER OF JAL SHAKTI
(SHRI C R PAATIL)
(a) to (d) : A statement is laid on the Table of the House.
1STATEMENT REFERRED TO IN REPLY TO PARTS (a) TO (d) OF STARRED QUESTION NO.
*80 TO BE ANSWERED ON 04.12.2025 IN LOK SABHA REGARDING “ECOLOGICAL HEALTH
ASSESSMENT OF THAMIRABARANI RIVER”
(a) Cleaning and rejuvenation of rivers is a continuous process. It is the primary responsibility of the
States/Union Territories (UTs) and local bodies to ensure proper treatment of sewage and industrial effluents
to the prescribed norms before discharge into rivers, other water bodies, coastal waters or land.
As per the Central Pollution Control Board (CPCB) report on ‘Polluted River Stretches for
Restoration of Water Quality’ through National Water Monitoring Program (NWMP), based on assessment
of water quality carried out in 2022 & 2023 i.e 5 different locations/ stretches from Tirunelveli Downstream
Side (D/S) To Kallidai - Kurichi, Tirunelveli on the Thamirabarani River, the Biochemical Oxygen Demand
(BOD) levels was ranging between 4.0 mg/L to 6.2 mg/L, placing the river stretch under Priority-IV
category. As per inputs received from CPCB, based on sampling taken at 9 locations in Tirunelveli District
in 2024 through SPCB, the BOD level is ranging from 2.0mg/L to 3.1mg/L which is showing decrease in
BOD levels, which means, an improvement in water quality.
(b) Under National River Conservation Plan (NRCP), one Sewage Treatment Plant (STP) of capacity 24.20
million litres per day (MLD) was set up between 2001 – 2007 at Tirunelveli with a cost of Rs 54.93 crore, for
pollution abatement river Thamirabarani. Atal Bhujal Yojana is not implemented in Thamirabarani river
basin. During the last 05 years several groundwater recharge works have been undertaken by the State
Government under MGNREGS Scheme in the Districts falling under Thamirabarani River Basin. Funds
under JJM are not maintained Basin wise.
(c) The annual run-off pattern depends on the rainfall pattern and the climatic conditions of a particular
region. As per the Central Water Commission, the annual average run-off of the Thamirabarani River at the
Murappanadu site in Tamil Nadu is 22 Million Cubic Metres (MCM) for the period 2014-15 to 2024-25.
However, the majority values of the actual run-off varies around this average.
(d) The Tirunelveli Municipal Corporation has informed that Tamil Nadu Government have formulated
proposals for setting up of STPs, Solid Waste Management, Biological Parks, etc. to contain pollution in
Thamirabarani River and River Rejuvenation work is also monitored through River Rejuvenation Committee
at State level. Central Pollution Control Boards/SPCB/Pollution Control Committee monitors river water
quality and industries to ensure compliance of the provisions of Environment Protection Act,1986 and
Water(Prevention & Control of Pollution) Act,1974. Central Water Commission monitors hydrological
parameters of the river through three Hydrological Observatories in Thamirabarani River.
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