Open Space Reservation (OSR) is a mandatory planning requirement under the Tamil Nadu Town and Country Planning Act, 1971 and allied Development Control Rules.
Every approved layout must earmark 10 % of its total extent as land reserved for community use — parks, playgrounds, or green zones. The developer executes a registered gift deed transferring that portion to the local body or planning authority, ensuring it remains public property.
The intent is simple: protect urban breathing space amid relentless construction. Courts have repeatedly treated misuse or diversion of OSR land as an encroachment on the collective right to clean air, recreation, and ecological balance.
Below are four recent judicial milestones (2022 – 2025) that defined the enforcement of OSR norms in Tamil Nadu.
⚖️ 1. Association of Vasanth Apartments Owners v. CMDA & Ors.
Supreme Court of India | 13 Feb 2023 | C.A. Nos. 1890-91 of 2010 & 7847-48 of 2013
Background
Residents of a 12-block complex (> 10,000 m²) had already gifted their OSR land to CMDA in 1994. When the land was later used as a connecting road, the association claimed ownership and demanded that it be retained as a private park.
Core Issue
Can flat owners reclaim or control OSR land once it’s gifted to CMDA?
Is Rule 19 of the Development Control Rules (10 % OSR + gift deed) constitutional?
Court’s Reasoning
- Once gifted, title vests *irrevocably in the local authority; residents have no proprietary right.
- CMDA may use the land for any legitimate public purpose, including a road, provided the objective remains public welfare.
- Rule 19 is a valid regulatory restriction, not *expropriation.
Order / Holding
- Appeals dismissed; CMDA’s and Corporation’s actions upheld.
- OSR reservation and gift-deed mandate affirmed as *constitutional.
Excerpt:
“Reservation of ten percent area for communal and recreational purposes is not a taking but a reasonable regulatory measure… execution of a registered gift deed ensures the land is not exploited later for private purposes.”
⚖️ 2. Trellis South Flat Owners Welfare Association v. CMDA & Ors.
Madras High Court | Justice M. Dhandapani | W.P. No. 17008 of 2022 | 14 Oct 2022
Background
The petition related to the alienation of OSR land by the CMDA authorities in favour of the respondents, viz., Chennai Metro Rail Ltd. (CMRL), the land that was maintained by the Trellis South flat Owners Welfare Association, who is the petitioner . CMDA alienated this OSR land to CMRL for infrastructure works.
Similar use of OSR land at Shenoy Nagar Park had earlier prompted a Supreme Court undertaking that the park would be restored — an undertaking the agencies had failed to honour.
Core Issue
CMDA promised to restore the park and greenery after using OSR land for Metro construction, but didn’t do it — so the High Court stepped in again to enforce accountability and monitor restoration through a committee.
Court’s Reasoning
- The State must honour its word; development cannot come at the cost of nature.
- The Court is the “custodian of law,” duty-bound to enforce environmental undertakings.
- Status reports filed by CMRL were “*bereft of detail” and failed to show genuine restoration.
Order / Directions
- Constituted a five-member Restoration Committee (Amicus Curiae + CMDA + CMRL + Horticulture Dept + Local Residents) to monitor regreening.
- Ordered periodic reports and field inspections.
Excerpt:
“Development should be directly proportional to maintenance of the environment… any destruction to the environment under the guise of development spells doomsday for the nation.”
🌳 3. S.P. Thiyagarajan v. Commissioner, Tirunelveli City Municipal Corporation
Madras High Court | 12 Apr 2022
Background
The petitioner sought permission to convert land reserved as a park/playground into residential plots.
Core Issue
Whether land earmarked as OSR in an approved layout can later be converted for private use.
Court’s Reasoning
- OSR dedication creates a permanent public trust.
- Neither the promoter nor subsequent owners can alter or sell it.
- Allowing conversion would “defeat the very scheme of the layout.”
Order / Holding
- Conversion refused.
- Directed the Corporation to preserve the area as a park and take action against any encroachment.
Excerpt:
“The land earmarked as park and playground must remain so for public benefit and cannot be alienated by any individual.”
🚇 4. CMRL Skywalk / Sewer Works on OSR Land (Vadapalani)
Madras High Court | Aug 2025 | Reported Times of India
Background
Residents objected to Metro authorities using OSR land (already gifted to CMDA) for constructing a skywalk and underground sewer line near Vadapalani.
Core Issue
To create a seamless, fare-controlled connection between Vadapalani Metro Phase I and Phase II stations, which will allow passengers to transfer between lines without exiting the fare zone. To lay a new sewage pipeline as the existing one for the Phase I station was damaged by roadworks. To determine Whether this temporary use of OSR land for civic infrastructure violates its protected status.
Court’s Reasoning
- Public infrastructure of unavoidable necessity can coexist with OSR preservation if usage is temporary and reversible.
- CMDA remains custodian; land cannot be commercially exploited or permanently re-purposed.
- Ordered strict timeline and post-completion restoration.
Order / Holding
- Allowed construction subject to restoration of the open area.
- Directed transparency and community updates.
Excerpt:
“Public convenience, when temporary and reversible, can coexist with preservation of OSR land… such projects shall not change its character or title.”
🏞️ The Importance of OSR and the Legal Stand on Encroachments
Open Space Reservation (OSR) land is not just another vacant plot — it is a legally protected public asset meant to serve as the green lungs of urban neighbourhoods. These spaces preserve ecological balance, improve air quality, and provide recreation and mental relief in crowded cities.
Once a layout is approved with designated OSR areas, that land becomes untouchable for private or commercial use. Any construction, sale, or alteration of OSR land amounts to encroachment on community property and is treated as an illegal act under the Tamil Nadu Town and Country Planning Act.
Courts in Tamil Nadu have consistently ruled that no individual, association, or authority has the right to alter the purpose of OSR land, and violators can face demolition, restoration orders, and even contempt proceedings.
🦁Verified.Realestate’s Take:
Calculate mandatory 10% open space reservation requirements for layouts and developments in Tamil Nadu. Determine whether to reserve land or pay fee-in-lieu based on plot size, jurisdiction, and development type as per 2024 regulations.
—— Visit https://verified.realestate/dashboard/utility/osr-calculator for more information.
*Irrevocably: Cannot be changed, taken back, or undone.
*Expropriation: When the government takes private property for public use, usually with compensation.
*Constitutional: Allowed or protected by the Constitution; legally valid under fundamental law.
*Bereft of detail: Lacking information or missing important specifics.