National Green Tribunal
Tribunal On Its Own Motion Suo Motu Based ... vs Member Secretary State Wetland ... on 24 September, 2025
Item No.1:-
BEFORE THE NATIONAL GREEN TRIBUNAL
SOUTHERN ZONE, CHENNAI
Wednesday, the 24th day of September, 2025.
[Through Physical Hearing (Hybrid Option)]
Original Application No.91 of 2023 (SZ)
IN THE MATTER OF
Tribunal on its own motion SUO MOTU based
on the news item published in 'The New
Indian Express', Chennai E-edition dated
30.06.2023, "Road being laid inside
marshland in Perumbakkam"
WITH
1. The Member Secretary
Chennai Metropolitan Development Authority
Thalamuthu Natarajan Building,
No.1, Gandhi Irwin Road,
Egmore, Chennai - 600 008.
2. District Collector - Chengalpattu
Collectorate, GST Road,
Chengalpattu, Tamil Nadu.
3. Additional Chief Secretary
Department of Environment & Climate Change,
No.1, Jeenis Road, Panagal Building,
Ground Floor, Saidapet,
Chennai, Tamil Nadu.
4. Member Secretary
Tamil Nadu State Wetland Authority
Panagal Maligai, Saidapet,
Chennai, Tamil Nadu - 600 015.
5. M/s. Casagrand Builder Private Limited
Rep. by its Managing Director,
Mr. Arun, Reg. Off. at NPL Devi,
5th Floor, New No.111, Old No.59,
LB Road, Thiruvanmiyur - 600 041.
(R5 Suo Motu impleaded as per order dt.12.07.2024)
6. M/s. Grande City Development Company LLP
Rep. by its Authorized Signatory,
Mr. C. Sakthivel,
6th Floor, Tower - C, Tek Meadows,
No.51, Rajiv Gandhi Salai,
Sholinganallur, Chennai - 600 119.
[R6 impleaded as per order dt.09.01.2025 in I.A. No.139/2024 (SZ)]
...Respondent(s)
Page 1 of 19
For Applicant(s): Suo Motu.
For Respondent(s): Mrs. P. Veena Suresh for R1.
Dr. D. Shanmuganathan for R2 to R4.
Mr. S.R. Rajagopal, Sr. Adv. a/w.
M/s. Allwin Godwin, Niranjana Pandian and
Rahul Kanna for R5.
M/s. Ganesh & Ganesh, K. Mohan,
Rathipriya & K. Jayaraman for R6.
Judgment Reserved on: 01st September, 2025.
CORAM:
HON'BLE Smt. JUSTICE PUSHPA SATHYANARAYANA, JUDICIAL MEMBER
HON'BLE Dr. PRASHANT GARGAVA, EXPERT MEMBER
JUDGEMENT
Delivered by Smt. Justice Pushpa Sathyanarayana, Judicial Member
1. The above Original Application was Suo Motu taken up by this Tribunal, based on the news item published in The New Indian Express, dated 30.06.2023, under the caption "Road being laid inside marshland in Perumbakkam".
2. It was stated that the private realtor was constructing a road across the marshland by dumping construction materials inside the water body, employing heavy machinery. The news item further mentioned that Mr. Deepka Srivatsava, Member Secretary, Tamil Nadu State Wetland Authority (TNSWA) was aware of it.
3. The notices were issued to the respondents through the Tribunal.
4. Originally, the Director, Directorate of Town and Country Planning (DTCP) was arrayed as Respondent No.1, who had filed the report dated 31.07.2023, stated that the DTCP grants approval for residential, commercial, industrial layout purposes, etc. Whereas the laying of roads anywhere in the State of Tamil Nadu does not come under the purview of the Page 2 of 19 DTCP. The Chennai Metropolitan Development Authority (CMDA) is the competent authority for approving the layout for residential, commercial and industrial purposes for the Chennai Metropolitan Area. As the Perumbakkam Marshland comes under the purview of the CMDA, any development made in the said marshland is to be done only with the permission of the CMDA.
5. Based on the said report filed by the Deputy Director, DTCP, the Director, DTCP, was removed from the array of parties and the CMDA was substituted in that place.
6. The CMDA, upon notice, has filed its reply dated 17.01.2024, stating that the 5th Respondent/ private builder had applied for planning permission/ building permit by furnishing the required documentary evidence, namely the Sale Deeds, Parent Documents, and Revenue Records such as Patta, FMB sketch, etc., to establish the ownership of the land. From the documents submitted and as per the records of the Revenue Authorities, the subject lands are patta lands and the same were situated in the primary residential use zone. The planning permission for the buildings in adjoining lands to the subject lands was also granted to M/s. Casa Grande, after proper inspection and scrutiny of the documents submitted before the authorities. The access road from the existing public road, which is termed as link road is usually gifted to the authorities, as given in the approved plan. According to the CMDA, the marshlands are situated in Sy. No.534/4 (20.74.0 Hectares) as per G.O. No.147 dated 12.05.2014. Therefore, the CMDA has granted approvals only based on the official records of the Revenue Authorities and also the 2nd Master Plan. According to them, the TNSWA, who is in-charge of the encroachments in the marshland, has to establish the same and take action for the waste materials dumped in the marshland. Accordingly, the CMDA has categorically stated that it is the TNSWA that has to establish the fact that the sites in dispute are marshland and protect the same from any encroachments.
7. In the second report dated 06.05.2024 of the CMDA, it is stated that no planning permission/ application for development is entertained by the CMDA in the land earmarked Page 3 of 19 for Pallikaranai Swamp Area. The TNSWA declared the Pallikaranai Swamp Area as a Ramsar Site in July 2022. The CMDA is in the process of preparing the 3rd Master Plan. In the absence of the details of the survey numbers covered under the Ramsar Site and the width of the influence zone around the Pallikaranai Swamp Area, along with guidelines for permitting developments, the CMDA will not be in a position to effect any changes in the Master Plan. As the CMDA is in the process of preparing the 3rd Master Plan for Chennai Metropolitan Area, action will be taken to incorporate appropriate guidelines and influence zone around the Pallikaranai Swamp Area, in consultation with the TNSWA. The CMDA, which is in the process of preparing the 3rd Master Plan, will be collecting the exact details of the Ramsar Site from the respective departments to include it in the 3rd Master Plan.
8. In the CMDA's report dated 19.08.2024, it is stated that the TNSWA has declared the Pallikaranai Swamp Area as a Ramsar Site in July 2022. However, consequent to the said declaration, the CMDA has not received any communication from the TNSWA giving the details of the boundary and the survey numbers of the Ramsar Site, in order to incorporate the boundaries into the Ramsar Site and to earmark the influence zone for Pallikaranai Swamp Area in the Master Plan for Chennai Metropolitan Area. The CMDA has categorically stated that it is in the process of the preparation of the 3rd Master Plan and action will be taken to incorporate the appropriate guidelines and influence zone around the Pallikaranai Swamp Area, in consultation with the TNSWA. In this regard, there was already a meeting between the CMDA, TNSWA and the Forest Department on 01.04.2024. Based on this, the TNSWA has shared the shapefile presenting boundaries of the Pallikaranai Swamp Area, in which survey numbers and subdivision details of the Ramsar Site/Marshland and influence zone of the same were NOT provided. Therefore, the CMDA had requested the TNSWA to share the list of survey numbers and subdivision details of Ramsar Sites and marshlands with its influence zone within the Chennai Metropolitan Area, along with the approved guidelines for permitting developments in such sites, supported by suitable maps for incorporating the same in the Master Plan as per the Page 4 of 19 letter dated 08.08.2024. The CMDA has stated that once the requested details are received from the TNSWA, the CMDA will proceed to incorporate the same in the Master Plan and follow the restrictions insisted for the Marshland/ Ramsar Site.
9. In the additional report dated 10.07.2025, the CMDA has stated that, as per the communications received from the TNSWA dated 30.04.2025 and 30.05.2025, the TNSWA informed the Directorate of Survey and Settlement (DoSS) that a total of 304 survey and subdivision numbers falling within the Pallikaranai Ramsar Site have been identified across seven revenue villages, namely Perumbakkam, Sholinganallur - 1, Pallikaranai, Perungudi, Jalladianpet, Injambakkam, and Okkiyam Thoraipakkam. The survey number and subdivision details, along with the KML and Shapefile delineating the boundary of the Pallikaranai Marsh/ Ramsar Site, along with 304 survey and subdivision numbers, were enclosed as email attachments to the communication. It was indicated that the survey number details seem to be approximate such as Sy. Nos.439 and 602 of Shollinganallur - 1 Village, which contained several residential buildings and a substantial area of marshland without any subdivisions. The CMDA has further stated that the confirmed data is awaited and once the confirmed data are received from the TNSWA, the CMDA will incorporate the same in the Master Plan. Further, it was stated that no planning permission has been issued by the CMDA in areas earmarked as Pallikaranai Swamp Area in the 2nd Master Plan land use map for the Chennai Metropolitan Area.
10. The District Collector, Chengalpattu District, in its first report dated 22.09.2023, has stated that the Deputy Tahsildar, Tambaram, Revenue Inspector and the Village Administrative Officer, Perumbakkam, inspected the subject area on 07.08.2023 and stated that the building and road are being constructed in Marshland owned by the Forest Department and the field was inspected by this office with Subordinate Officers. He has also provided the Revision Survey Re-Settlement Paisathi Register (RSR) particulars as well as the UDR 'A' Register details. He has also stated that the building image that appeared in the Page 5 of 19 newspaper is on the Sy. No.534, which is the Government Manavari Waste Barren Land. The details given in the said report are only about Sy. No.534 and its subdivisions and not about the disputed Sy. No.286/1, etc.
11. In the report dated 16.09.2024, the District Collector, Chengalpattu District, has stated as per the 1911 RSR Record in respect of Perumbakkam Village in Chengalpattu District, the Sy. No.286 is a patta land, wherein a Ryotwari patta had been granted to private individuals. As they are Ryotwari Patta, they cannot be categorized as conditional pattas. The District Collector has further stated that the Sy. No.534/4 of UDR 'A' Register is classified as 'Sathupu Nilam' (Marshland), admeasuring an extent of 20.74.0 Hectares, has come into existence by subdividing the Sy. No.430 of RSR Register classified as Perumbakkam Reserved Forest, admeasuring 643.90 Acres. As per the report, barring the Sy. No.534/4, no other subdivisions created from the original Sy. No.430 of the RSR Register has been classified as 'Sathuppu Nilam' in the revenue records. From the available records, no patta has been issued to any private individual or organization in respect of the land comprised in the aforesaid marshland in Sy. No.534/4 of UDR 'A' Register.
12. In the next report dated 17.10.2024 of the 2nd Respondent/ District Collector, the following facts are set out:
The records since 1911 were perused, as per which, the Perumbakkam Village is originally a Ryotwari Village. The entire village of Perumbakkam consisted of 2055.60 Acres of land as per the RSR Register. As per the RSR, 1911, the entire village land was broadly classified into two categories, namely Government land and Inam land. The category of Government land consisted within itself the following sub-categories i.e. Government Wet - Patta Wetlands, Government Dry - Patta Dry lands, Government Poramboke - Government lands. Accordingly, the Sy. Nos.286/1 and 286/2 of Perumbakkam Village were classified as 'Government Wet', as per the RSR and therefore, they are patta lands. The said survey numbers also stand in the name of private individuals with specific patta numbers assigned to each of the pattadars. Therefore, during Page 6 of 19 the Updating Register Scheme (UDR), the above lands were categorized as 'Ryotwari Wetland' owned by private patta holders. The status of the patta lands, as per the UDR 'A' Register, is also furnished in the report by the District Collector, who has categorically stated that Sy. No.286 and subdivisions have never been classified as Government Poramboke Lands throughout the history of those lands since the year 1911.
13. The District Collector filed yet another report dated 17.04.2025, which is after verifying the records and certified copies of the Sale Deeds executed, which were called from the concerned authorities and Sub Registrar, Tambaram, connecting Perumbakkam Village. Sy. No.285 was perused by the District Collector from the year 1901 till date by summoning the documents from the Sub Registrar. It is stated that Sy. No.285 of Perumbakkam Village, Tambaram Taluk, has been recorded as in the RSR Fasli Register of Sy. No.279 of Perumbakkam Village. The RSR shows that the Revision Survey Number and the Old Survey Number are 285 only. In the UDR 'A' Register, the said Sy. No.285 has been subdivided into 285/1A, 1B, 2A, 2B and classified as wetlands. Subsequently, the said Sy. No.285 of the Perumbakkam Village has been recorded in the Computerized 'A' Register, which also shows that the Sy. No.285 and subdivisions are 'Ryotwari Wetlands'.
14. The District Collector has also enlisted the documents, which are the sale transactions from the year 1966 relating to Sy. No.285 only. Accordingly, it was stated by the District Collector that the RSR 1911, UDR 'A' Register, Computerized 'A' Register, Village Adangal Records for the Fasli year 1434 (Gregorian Calendar year 2024) and the sale transaction details obtained from the Sub Registrar, Tambaram, and found that the land comprised in Sy. No.285 (Patta land) is classified as 'Ryotwari Nanja' in the revenue records.
15. The 4th Respondent, which is the Tamil Nadu State Wetland Authority (TNSWA), in its original report dated 23.08.2023, has stated that the land in question in Perumbakkam was inspected on 03.07.2023. It is found that the area is a marshland and the said road lies within the zone of Page 7 of 19 influence and adjoining to the boundary of the Ramsar site i.e. Pallikaranai Marshland Reserve Forest, which is approximately 150 meters away from the Ramsar site boundary. The area is a patta land belonging to M/s. Casa Grande Builders, as per the claim made by the Site Engineer. The pathway has been developed by the builders through mobilizing the construction materials within the marshland's ecosystem. The waste materials are being dumped in the Pallikaranai marshland ecosystem. After citing the order passed in W.P. No.1081 of 2017 by the Hon'ble High Court of Madras, it is stated by the TNSWA that the Pallikaranai Marshland has been designated as a Ramsar Site on 08.04.2022 and the said activity of laying road adjoining the Ramsar Site may adversely affect the hydrological, ecological and socio-economic parameters of the wetland, making the marshland more vulnerable to the anthropogenic factors. Accordingly, the Member Secretary, CMDA, was advised to ensure that the builders or individuals do not fragment the Pallikaranai Marshland by way of the construction of road and building adjacent to the marshland, which has become a wetland of international importance. The TNSWA also referred to the communication dated 19.07.2023 issued to the Member Secretary, CMDA.
16. The TNSWA, in its report dated 13.06.2025, has stated that a meeting was convened by the CMDA on 07.10.2024 to ascertain the survey and subdivisions that fall within the Pallikaranai Marsh Ramsar site and it was decided that the survey and subdivision numbers of the entire area of Pallikaranai Marsh Ramsar Site will be furnished to the CMDA with the support of the Directorate of Survey and Settlement (DoSS), in order to incorporate the same in the Master Plan 2026. The TNSWA has further stated that the digital survey number details provided appear to be approximate and not entirely accurate. Therefore, the communication was sent on 30.04.2025 to the DoSS, which is a competent authority in such matters, to verify the survey data, which is now being carried out by the DoSS. Accordingly, once the survey numbers, which fall within the Pallikaranai Marsh Ramsar Site boundary, are finalized, the Page 8 of 19 survey numbers falling within the zone of influence of the Ramsar Site can also be ascertained.
17. In the next status report dated 10.07.2025 filed by the TNSWA, it has referred to the Integrated Management Plan (IMP) prepared by M/s. Care Earth Trust, Chennai, for Pallikaranai Marsh, in which a general zone of influence of 1 Km has been demarcated from the boundary of the marshland using the Direction Model and Buffer Model. The guidelines for delineating the zone of influence for wetlands with diffused drainage, such as Pallikaranai Marshland, are provided in the guidelines for implementing wetlands. In the above-referred IMP, it is said to be mentioned that the hydrological influence of the Pallikaranai Marsh land seems to be limited to sheet flows and very minimal channelized flow due to connecting channels being converted to other land uses. In this regard, though the zone of influence has been delineated as 1 Km due to the presence of patta lands and high urbanization of lands surrounding the Pallikaranai Marshland, it would be prudent to delineate the zone of influence based on the inlet, outlet channels and satellite wetlands found in the catchment area that can be managed and has a significant effect on the Pallikaranai Marshland. This shall aid in the effective conservation and management of the marshland. After the declaration of Pallikaranai Marshland as a Ramsar Site in the year 2022, the NCSCM, Chennai, has taken up the work of preparation of IMP based on the Wetlands (Conservation and Management) Rules, 2017. The zone of influence shall be delineated during the process of preparation of IMP and prescriptions/regulations for the zone of influence shall also be part of IMP. After the approval of IMP, the zone of influence shall be effective.
18. The 4th Respondent/ TNSWA's report dated 03.08.2025 states that as per the Wetlands (Conservation and Management) Rules, 2017 and the guidelines for their implementation issued by the MoEF&CC, the zone of influence of the wetland is not a fixed or uniform area but is determined based on site-specific factors such as local hydrology, topography, drainage patterns and adjoining land use. Therefore, the extent of the zone of influence, which varies from Page 9 of 19 one wetland to another, must be delineated accordingly using scientific methods, including digital elevation models and field validation. As per the guidelines, the zone may include directly draining basins, peripheral agricultural lands and adjoining settlements, depending on their impact on the ecological functioning of the wetland. It is stated that the drainage canal from Perumbakkam Lake carries water from the upper catchment area into the Pallikaranai Marshland. This canal passes through Sy. Nos.286 and 472. Any alteration in these areas is likely to significantly affect the inflow of water into the Pallikaranai Marshland, particularly during the monsoon, thereby disrupting the hydrological connectivity of the wetland and potentially causing inundation in the surrounding settlements. Additionally, there are 50 stormwater inlets that discharge directly into the Pallikaranai Marsh Reserve Forest. Based on the report received from the DoSS, the TNSWA states that the Sy. No.286 falls within the vicinity of the Ramsar boundary with a measured distance of approximately 246.99 Meters from the said boundary. As per the National Disaster Management Guidelines on the management of urban flooding, any unauthorized development in this area is illegal and may adversely affect the local population due to potential overflow of water.
19. The 5th Respondent, which is the Project Proponent, in its reply dated 20.08.2024, has stated that it has considered the development of properties situated in Sy. No.283/1A, 283/1B, 283/2A, 284/1, 284/3, 286/2A, 286/2B, 286/2C (Pt), 285/1A, 285/1B2, 285/1B3, 285/2B2, 285/2B3, 286/1B2 (Pt), 285/1B1, 285/2B1, 286/1B4 (Pt), 286/1B3 (Pt), 473/1A2 (Pt) and 473/1AD at Perumbakkam Village, in an extent of 970.72 Cents. The Project Proponent also claims to have entered into a General Power of Attorney dated 01.06.2023 and an Agreement of Sale on 01.06.2023. According to it, the said area is classified as a 'Primary residential use zone' by the CMDA. The patta in relation to the proposed project is mutated. Thereafter, the Project Proponent applied for a land survey of the subject land in relation to the Sy. No.286/2A before the DoSS. For the purpose of the survey, at the request of the authorities, the subject land in Sy. No.286 was to be levelled. To facilitate Page 10 of 19 the same, the 5th Respondent carried out the levelling activities with respect to the subject land in Sy. No.286, by using certain scrap construction materials. It is categorically stated that the Project proponent had not laid any access road on the subject land in Sy. No.286 and it is only the construction materials that were used to level the ground in the subject land. According to the Project Proponent, the Sy. No.286 has not been notified as a wetland or marshland or zone of influence under the Wetlands (Conservation and Management) Rules, 2017. The activities undertaken by the Project Proponent in the subject land are only for the proposed development of the project and have levelled the subject land, which was only a vacant site.
20. Heard the learned counsels appearing for the official respondents as well as the learned Senior Advocate, Mr. S.R. Rajagopal, appearing for the Project Proponent and also perused the materials available on record.
21. The Pallikaranai Marsh Reserve Forest in Chennai is a well-known South Indian Marshland. It could be said to be the last surviving marshland in the region, which serves as a vital flood buffer, a rich habitat for diverse flora and fauna, including migratory birds and endangered reptiles.
22. From time immemorial, the wetlands have played a critical role in fostering culture and civilization. Unfortunately, they did not receive due consideration of appreciation. As a result, wetlands have diminished in size and quality at an alarming rate throughout the globe. Perhaps it was considered as a wasteland to be filled with garbage and other waste. The real estate activities around the urban centres are also a threat to the wetlands.
23. Only in the year 2022, the Pallikaranai Marshland was designated as a Ramsar Site, having realized that it acts as an aquatic buffer for Chennai and surrounding districts, absorbing flood waters and releasing them during dry spells. The urban development, including the construction of IT corridors and residential areas, has drastically shrunk the original area of the marsh. This has resulted in the sewage and sullage water Page 11 of 19 and industrial effluents contaminate the marsh. Additionally, the solid waste dumped also pollutes the ecosystem, reducing its water storage capacity.
24. The value of the wetlands can be expressed in many ways. The ecosystem services offered by the wetland include flood water storage and control, recharge of aquifers, water quality improvement, while habitats for fish and wildlife and several other animals and plant species. Besides, the wetlands have high aesthetic and heritage value, which provides opportunities for recreation and research. The wetlands also stabilize the levels of available Nitrogen, Atmospheric Sulphur, Carbon dioxide, and Methane. Thus, the invaluable ecosystem services provided by marshlands, which are recognized globally for their significance, are now being taken for granted. While the marshlands have inherent and unique characteristics of wetlands, which function like a natural tub or sponge, storing water and releasing it gradually. It has been neglected by allowing infrastructure development, land reclamation and over harvesting. These have caused hydrological perturbations, pollution and several after effects. After neglecting the natural resources available, the construction of a sponge park with recreational facilities to mitigate the urban flood risk is being contemplated by the Government.
25. In the wake of the above facts, this Tribunal has to take judicial cognizance of the news item titled "Road being laid inside marshland in Perumbakkam". The said Perumbakkam wetland is an extension of the larger Pallikaranai marshland system. Pallikaranai is a well-known marshland, but Perumbakkam is a suburb known for its IT companies and residential developments and it feeds into the main marsh. Perumbakkam Wetland acts as a feeding source for the Pallikaranai Marsh with rainwater flowing from the Perumbakkam Wetland into the Pallikaranai Marsh, before reaching the Okkiyam Maduvu Canal.
26. As per the newspaper report, a private realtor was allegedly constructing a road across the Perumbakkam Marshland and tonnes of construction materials and soil were Page 12 of 19 dumped inside the water body and heavy machinery was deployed to fill the area.
27. The Perumbakkam Village and the nearby area of Pallikaranai are in close proximity within Chennai and they are largely influenced by the same weather systems. Therefore, Perumbakkam is directly within the zone of influence of the Pallikaranai Marshland.
28. The report of the District Collector has stated that the category of Government land consisted of three subcategories, namely (i) Government Wet - Patta Wetlands (ii) Government Dry - Patta Drylands and (iii) Government Poramboke - Government Lands. The survey numbers under consideration i.e. 286/1 and 286/2 of Perumbakkam Village, were originally categorized as Government Wet, as per the RSR and therefore, they are patta lands. The report further stated that the said survey numbers, as private patta lands, has been continuing as such since the time of the RSR Register till date. Therefore, they do not come under the classification of Government Poramboke lands.
29. The TNSWA, which is the 4th Respondent, has also stated that M/s. Care Earth Trust, Chennai, had prepared the IMP for Pallikaranai Marshland, in which a general zone influence of 1 Km has been demarcated from the boundary of the marshland using the Direction Model and Buffer Model. The guidelines for delineating the zone of influence for wetlands with diffused drainage are provided for implementing the Wetlands (Conservation and Management) Rules, 2017. The report has stated that the hydrological influence of the Pallikaranai Marshland seems to be limited to sheet flows and very minimal channelized flow due to connecting channels being converted to other land uses. Though the zone of influence has been delineated as 1 Km due to the presence of patta lands and high urbanization of land surrounding the Pallikaranai Marshland, it would be prudent to delineate the zone of influence based on the inlet and outlet channels and satellite wetlands found in the catchment area that can be managed and have a significant effect on the marshland. However, it is stated by the TNSWA Page 13 of 19 that the work of preparation of IMP based on the Wetlands Rules, 2017, has been taken up and the zone of influence will be part of the IMP and only after the approval of IMP, the zone of influence shall be effective.
30. The TNSWA has also stated that based on the digital survey and subdivision boundary records that are found in and around the Pallikaranai Marsh Ramsar Site, the TNSWA has identified 304 survey and subdivision numbers across seven revenue villages, including the Perumbakkam Village. As it was felt that the details were only approximate and not accurate, it was directed to verify the same by the DoSS. Thereafter, the TNSWA and the DoSS have identified survey numbers and subdivisions falling within the Pallikaranai Marshland, which is the Ramsar Site. The preparation of a brief document of the Ramsar Site in Chennai, undertaken by Anna University, should have been made ready, based on which the zone of influence should have been decided.
31. In this regard, the subsequent report of the TNSWA stated that the zone of influence of the wetland is not a fixed or uniformed area but it is determined based on site-specific factors such as local hydrology, topography, drainage pattern and adjoining land use. However, it is stated that the revision of the existing IMP is currently under progress, in which the delineation of the zone of influence will be carried out and will be included in the revised IMP.
32. Mr. S.R. Rajagopal, the learned Senior Advocate appearing for the 5th Respondent, submitted that the patta with respect to the Sy. No.286 is in the name of M/s. Grande City Development Company LLP. For the purpose of the survey and at the request of the authorities to do an effective survey, the subject land in Sy. No.286 had to be levelled. To facilitate the same, the Project Proponent had carried out the levelling activities with respect to the subject land in Sy. No.286 used scrap construction materials and levelled the ground. It was further argued that the Sy. No.286 has not been notified as a wetland or marshland or a zone of influence under the Wetlands (Conservation and Management) Rules, 2017. Further, it was Page 14 of 19 reiterated that the said survey number is a primary residential use zone as per the 2nd Master Plan of the CMDA.
33. In this regard, he also invited our attention to the communication from the Chief Engineer, Water Resources Department (WRD) to the CMDA dated 24.09.2019 with reference to the planning permission for the proposed construction of a high-rise building group development for two blocks in Sy. Nos.470, 471, 472/1, 472/2 and 476/1B of Perumbakkam Village with specific remarks on the inundation point of view, along with permission for the construction of culvert access over the channel portion. In the said communication, based on the revenue records and considering the site conditions and technical opinion along with NOC on the inundation point of view, the planning permission for the proposed construction was issued to the CMDA, subject to certain conditions and technical suggestions besides the other mandatory clearances and statutory permissions from various departments. Among the various terms and conditions, a cut and cover section were also made mandatory in a size specified therein and as per the directions of the Departments of Public Works Department/ Water Resources Department Field Engineers and standards. The said cut and cover section will be the property of the Government, PWD and WRD, after the construction is over.
34. A similar communication was issued by the Chief Engineer, WRD, to the CMDA dated 17.07.2025 (which is pending the present proceedings) regarding the planning permission for the proposed construction of a high-rise group development for the project presently in question in Perumbakkam Village.
35. Here also, the department had already accorded NOC along with specific remarks on the inundation point of view for planning permission and construction of a high-rise building with various conditions. The communication has also specifically mentioned about the historical rainfall of 2015 and 2023 (2100 MM per Annum) for the entire surrounding lakes had a surplus and some of the upper tanks were breached. So, the entire area of the Sholinganallur, Perumbakkam, Chemmanchery, Navalur Page 15 of 19 and downstream of Perumbakkam Tanks ayacut area, including the applicant's site, was submerged and inundated up to a level of 4 - 5 feet. As the site is in close proximity with the surplus course of Perumbakkam Tank and the Perumbakkam Big Tank (Periya Eri), it could be susceptible against inundation and hence, the inundation potential must be ascertained based upon the existing field levels. Therefore, in the lines of the Planning Permission (2019), the Chief Engineer, WRD, has mentioned that to protect the site safe against any inundation in the near future, it is recommended to raise the field level from 5.4 to 5.9 Meters below sill level of Sluice No.2 of Perumbakkam Big Tank, which is due to the existing terrain condition where the terrain slopes from west to east direction. So, with the other conditions, the planning permission was issued to the CMDA subject to the special and technical conditions, which included the cut and cover system section with inlet arrangements.
36. On the strength of the said recommendation, it was submitted by Mr. S.R. Rajagopal, the learned Senior Advocate, that necessary precautionary provisions will be made by the Project Proponent in the event of inundation.
37. The purpose of registering the above-captioned Original Application is to avoid any kind of permanent structures or damage to the wetland/ marshland and its zone of influence.
38. While the Project Proponent contends that the zone of influence study has not yet been conducted, the WRD, relying on the findings of M/s. Care Earth Trust, Chennai--who prepared the Integrated Management Plan (IMP) for the Pallikaranai Marshland--states that the zone of influence or percolation has been delineated as 1 km from the boundary of the marshland using the Direction Model and Buffer Model. However, in the latest report dated 29.08.2025, the WRD has stated that the NCSCM has undertaken the preparation and upgradation of IMP in accordance with the Wetlands (Conservation and Management) Rules, 2017 and the revision of the existing IMP is currently under progress. As part of the process, the delineation of the zone of influence will be carried out and the corresponding prescriptions or regulations for the zone will be included in the Page 16 of 19 IMP. The zone of influence will become effective only upon approval of the updated IMP.
39. While so, would it be appropriate for the authorities to grant any planning permission/ approval when the said process is under consideration?
40. Admittedly, the Sy. Nos.470 and 471 are very much within the zone of influence and the very same Project Proponent had completed the construction in Sy. No.470 and the construction is under progress in Sy. No.471. The application mentioned area is on the west of the said constructions. The mere fact that constructions have been permitted in Sy. Nos. 470 and 471, which fall within the Ramsar Site Influence Area with approval from the competent authorities, does not preclude the authorities from refusing planning permission or approval for an adjacent site, particularly when it is yet to be determined whether the said site falls within the zone of influence.
41. Admittedly, the proposed construction is within 1 Km from the boundary of the Pallikaranai marshland. The above 1 Km distance is said to be the zone of influence or percolation as per the Care Earth Trust, Chennai, which prepared the IMP. The Pallikaranai marshland is one of the last remaining natural wetlands of Chennai City, which is locally known as 'Kazhuveli', which means a floodplain or a waterlogged area. The southern and western boundaries are bounded by mixed residential and institutional land use. To the north of the marshland, there are dense human habitations and public infrastructure, such as the Mass Rapid Transport System (MRTS). The topography of the marsh is such that it always retains some storage, thus farming a classic wetland ecosystem. It is one of the few natural coastal aquatic habitats that qualify as a wetland in India. The seasonal dynamics in water volumes have rendered the Pallikaranai marsh a biodiversity-rich South Indian Wetland.
42. In fact, large parcels of the Pallikaranai marsh have been lost due to the reduction of wetland area, fragmentation and ad-hoc manipulation that destroyed 90% of the marsh. The remaining 10%, which is now being protected, is the last hope Page 17 of 19 for the city of Chennai. The city of Chennai and its surroundings are known for their water-stressed areas. The rainwater harvesting structures and other mechanisms can be created wherever possible. However, the alternative sources of water from water bodies can be identified for permanent solutions. It would be appropriate to restore the entire wetland complex rather than focusing on individual water bodies. Admittedly, the extensive infrastructure developments have already shrunk the wetland, resulting in a thinning of the water flow. In this regard, the only site-specific ecotourism initiatives could be formulated keeping the local carrying capacity in consideration.
43. It appears that the Water Resources Department had already granted permission for the construction of a culvert access over the channel portion, which is right in the zone of influence. Though the Ramsar Convention was in the year 2022, from the year 1986, the importance of the marshland has been emphasised and the preservation of the same was reiterated. The authority concerned, namely the TNSWA, has not yet surveyed the Ramsar site and declared the area to be preserved. The IMP prepared by M/s. Care Earth Trust has already recommended a general zone of influence of 1 Km to be demarcated from the boundary of the marshland.
44. The Water Resources Department has given the technical suggestion to raise the field level from 5.4 to 5.9 Meters below the sill level of Sluice No.2 of Perumbakkam Big Tank, considering the terrain condition, where the terrain slopes from west to east. Be that as it may, now the NCSCM has undertaken the preparation of IMP in accordance with the Wetlands (Conservation and Management) Rules, 2017 and the revision of the existing IMP is currently in progress. In the said exercise, the delineation of the zone of influence will also be carried out. Until the preparation of the IMP is completed, the authorities shall not grant any approvals, sanctions, or permissions that may alter the character of the marshland.
45. Even if the Project Proponent was allowed to construct in Sy. Nos.470 and 471, with the technical suggestions given by the Water Resources Department, they are not only Page 18 of 19 falling within 1 Km from the boundary of the marshland but are also adjacent to the same, falling within the zone of influence, which is prohibited. Even assuming that the impugned project in this Original Application is situated to the west of the projects permitted to be constructed by the Project Proponent, it is admittedly located within the zone of influence of 1 km, i.e., at a distance of less than 150 meters. Even though the Water Resources Department has sent a communication dated 17.07.2025 regarding the planning permission for the proposed construction, the CMDA is yet to grant the planning permission. The CMDA is also in the process of preparing the 3rd Master Plan, for which, it is awaiting the survey report from the TNSWA and the DoSS. Therefore, any approval on the marshland and its zone of influence can be granted by the CMDA only after the IMP is prepared based on the survey taken or to be taken by the TNSWA.
46. Hence, the authorities concerned, namely the Water Resources Department (WRD), Tamil Nadu State Wetland Authority (TNSWA), and Chennai Metropolitan Development Authority (CMDA), are directed to work in coordination to expedite the preparation of the Integrated Management Plan (IMP), based on the survey of the Ramsar Site Wetland and the guidelines required for maintaining the Ramsar Site. Hence, while considering the grant of planning permit by concerned authorities, the above directions should be strictly followed.
47. With the above directions, the Original Application [O.A. No.91 of 2023 (SZ)] is disposed of.
Sd/-
Smt. Justice Pushpa Sathyanarayana, JM Sd/-
Dr. Prashant Gargava, EM Internet - Yes/No All India NGT Reporter - Yes/No O.A. No.91/2023 (SZ) 24th September, 2025. Mn.
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