Chapter IX Macro Drainage System in CMA
Chapter IX Macro Drainage System in CMA is CMDA planning guidance on flood management, waterways, water bodies and drainage within CMA. It identifies flood-prone and conservation areas, calls for protection and restoration of water bodies, and restricts unsuitable development in sensitive locations such as Pallikkaranai swamp and the Redhills catchment area.
What the chapter covers
Chapter IX Macro Drainage System in CMA describes the major rivers, tanks, reservoirs and drainage conditions affecting Chennai City and its surrounding areas. The principal rivers are the Kosasthalaiyar River, Cooum River and Adyar River. Major water bodies include Sholavaram Tank, Red Hills Tank and Chembarambakkam Tank.
The chapter records regular flooding in developed and settled areas despite 158 km of drainage and extensive water storage systems. It links flooding to silted waterways, encroachments and structures that obstruct channels and banks, development on former tank and anicut areas, inadequate local drainage and geological conditions that limit water infiltration in the south-west.
What the land use plan does
The CMDA land use plan uses macro drainage conditions to guide development and flood remediation. Its main provisions are:
- Important macro drainage features are identified, together with the extent of conservation areas.
- Lakes and water bodies are to be protected from encroachment.
- Existing encroachments are to be removed so that water bodies can be restored to their original state.
- Areas subject to annual flooding are identified for remediation by local bodies working with the PWD.
- Development may be prohibited or severely restricted where uses other than open space are unsuitable.
- Pallikkaranai swamp and the Redhills catchment area are specifically identified as sensitive areas.
- Safeguards against undesirable development near waterways and water bodies are incorporated in the Development Regulations.
These provisions may matter to buyers, owners and developers where land lies near a water body, waterway, flood plain, catchment or identified conservation area.
Drainage responsibilities and strategy
The PWD is identified as the principal stakeholder for macro drainage, with responsibilities also involving Chennai Corporation, Metrowater and the Revenue department. Municipal corporations, municipalities and other local bodies are responsible for micro drainage and storm water drainage.
The planning strategy calls for additional storage capacity, a network of open spaces that can moderate floods, integration of micro drainage with the macro system, and local micro drainage plans prepared in consultation with the PWD. The Plan also recommends implementing measures from the MMFR/SWD Master Plan Study Report.
Monitoring
A Shelter and Infrastructure Committee, including government and non-government stakeholders and experts, is proposed to monitor drainage policies and strategies. It is intended to meet at least once every three months, or more often when needed, and may create specialist working groups.
This summary is generated from the source document to help you find what is relevant. The PDF above is authoritative. For advice on your own property, use LandLens One or speak to a qualified professional.
Common questions
Can development be restricted on land near Pallikkaranai swamp?
Yes. The CMDA land use plan identifies Pallikkaranai swamp as an area where development other than appropriate open-space use must be prohibited or severely restricted.
What does the chapter say about encroachments on lakes and water bodies?
Lakes and water bodies must be protected from encroachment. Existing encroachments should be removed so that the water bodies can be restored to their original state.
Who is responsible for storm water drainage in local areas?
Municipal corporations, municipalities and other local bodies are responsible for micro drainage and storm water drainage. Their systems are intended to be integrated with the macro drainage system.
Does the land use plan identify areas that flood every year?
Yes. The CMDA land use plan identifies critical areas subject to annual flooding so that local bodies can undertake remediation measures in collaboration with the PWD.
