Chapter X Macro Drainage System in CMA
Chapter X Macro Drainage System in CMA, issued by the Chennai Metropolitan Development Authority, describes the rivers, tanks, canals and drains that form the Chennai Metropolitan Area's macro drainage system and summarises past flood studies and improvement proposals. It identifies the public agencies responsible for storm water management, but does not state any parcel-level land use change, building restriction or approval requirement.
What the chapter covers
Chapter X Macro Drainage System in CMA explains how water and flood flows move through the Chennai Metropolitan Area. The area is crossed by the Kosasthalaiyar, Cooum and Adyar rivers and contains major tanks, canals, channels, ponds and flood accommodators.
The Chennai Metropolitan Area receives most of its rainfall between October and December. Its generally flat terrain and development within former tank beds and agricultural lands contribute to flooding risks, particularly where local drainage is inadequate or not operating.
Main waterways and storage areas
The macro drainage network described by the Chennai Metropolitan Development Authority includes:
- The Kosasthalaiyar River, which flows from Poondi Reservoir through Thiruvallur District and enters the sea at Ennore.
- The Cooum River, which flows from Kesavaram Anicut through Kancheepuram District and reaches the sea near Fort St. George.
- The Adyar River, which originates from the Pillapakkam and Kavanur tank groups and reaches the sea near Adyar.
- Sholavaram, Red Hills and Chembarambakkam tanks, which have water storage and flood management roles.
- Buckingham Canal, Otteri Nullah, Captain Cotton Canal, Mambalam Drain, Velachery Drain and Virugambakkam-Arumbakkam Drain.
- About 320 tanks and lakes that were previously used for irrigation and now also accommodate floods.
The listed major waterways have a combined length of 157.8 kilometres within the Chennai Metropolitan Area.
Public agency responsibilities
The Chennai Metropolitan Development Authority is responsible for project packaging and management, monitoring and coordination. The Public Works Department plans, designs and implements macro drainage works, while the Chennai Municipal Corporation handles micro drainage works. The Tamil Nadu Slum Clearance Board formulates and implements rehabilitation and resettlement packages.
Flood history and proposals
Government records identify major Chennai floods in 1943, 1976, 1985, 2002 and 2005. The chapter links severe flooding to failures of major rivers and drainage systems, while regular flooding in low-lying areas is associated with inadequate or inoperative local drainage.
Recommendations described in the chapter include improving Captain Cotton Canal, diverting selected tank surpluses, providing an additional discharge arm across Manali-Tondiarpet Road and constructing a short cut canal to the sea in the Thiruvottiyur area.
Relevance to property owners and buyers
Chapter X Macro Drainage System in CMA provides area-level information about waterways, flood paths and drainage responsibilities. It may help readers understand broader flood conditions near a property, but it does not identify individual survey numbers or impose a stated property-specific restriction.
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
Does this chapter change the land use classification of my property?
No land use reclassification or parcel-specific change is stated in Chapter X Macro Drainage System in CMA. The chapter describes the regional drainage network, flood history and proposed drainage improvements.
Which agency handles major drainage works in the Chennai Metropolitan Area?
The Public Works Department plans, designs and implements macro drainage works. The Chennai Metropolitan Development Authority handles project packaging, management, monitoring and coordination.
Why are low-lying parts of Chennai described as vulnerable to flooding?
The chapter states that Chennai and its surroundings are generally flat. It also attributes recurring flooding in low-lying areas to inadequate or inoperative local drainage infrastructure.
Can I use this chapter to determine whether a specific property will flood?
The chapter provides regional information about rivers, tanks, canals, drains and past flooding. It does not provide a property-specific flood assessment or identify individual survey numbers.
