About 20 kilometres of Colombo’s 469-kilometre canal and drainage network have been upgraded since 2014, Cabinet Spokesman and Minister Dr. Nalinda Jayatissa said on Wednesday — roughly four per cent of the system in twelve years.
Speaking at the weekly Cabinet press briefing, Jayatissa put the capital’s recent flooding down chiefly to rainfall intensity: between 129mm and 150mm fell in one to two hours, the Daily Mirror reported.
The comparison he drew is the story. The existing network was designed for about 30mm of rain an hour. The sections upgraded from 2014 onwards were built to take up to 102mm an hour. Even the upgraded four per cent, in other words, would have been overwhelmed last week — and the remaining 96 per cent is working to a standard roughly a fifth of what the rain delivered.
Norris Canal: eight households left
On the cleaning of the Norris Canal near the National Hospital, Jayatissa said eight households have yet to be relocated, with Rs. 11 million in compensation prepared.
He said urban flooding could not be handled by the Colombo Municipal Council alone, referred to a rapid action programme running under the direction of the Presidential Secretariat, and named unauthorised structures, irregular development and improper waste disposal as contributors to blocked drains. Public cooperation was essential, he said, urging residents to stop dumping non-biodegradable waste into drains and canals.
The CMC’s account differs in detail
Municipal Commissioner A.D.S. Rohana gave the Daily Mirror a separate set of figures the same day: Colombo receives about 2,500mm of rain a year; the canal system built in the Dutch period discharges some 350mm a day; the British-era drains were designed for 30mm an hour, matching the minister; and the recent event he cites is 68mm in 40 minutes.
Rohana said people on land obstructing drainage would be relocated and that four families have already been moved. Read alongside the minister’s eight households still to go on the Norris Canal, those counts are not necessarily the same programme and should not be added together — neither filing links them.
He also said authorities are planning climate adaptation measures for residents and commuters, arguing that reliable same-day forecasts would let the city plan around them. No specific scheme is named.
Where this sits
The figures land after a fortnight in which flooding closed roads and rail, the Prime Minister’s two-week canal-cleaning deadline passed unimplemented, the CMC set up a special task force and began enforcement against unauthorised construction, and the opposition and former ministers traded blame over who built or neglected what. Wednesday is the first time the government has quantified how much of the network has actually been modernised.
Not reported
Neither filing explains why only 20km was upgraded in twelve years — no budget, no programme name, no responsible agency, and no account of what stalled. Neither gives a cost or timetable for upgrading the remaining 449km, says whether any such plan exists, or identifies which stretches were done. The two rainfall figures are not reconciled, no date is attached to either, and the “climate adaptation measures” remain unspecified.
On sourcing: both filings are Daily Mirror, so this report rests on a single verified newsroom, though they carry different reporters and different speakers. Searches of Hiru, NewsFirst, Daily News, news.lk, Island, Daily FT and EconomyNext found no independent account of Wednesday’s briefing figures at the time of writing.
Sources
- Only 20km of Colombo’s 469km drainage network upgraded since 2014 – Minister — Daily Mirror, 11 November 2026
- Authorities plan climate adaptation measures; families obstructing drainage to be relocated — Daily Mirror, 11 November 2026
- Why did Colombo go underwater in just two hours? — Daily Mirror, 11 November 2026
Update, 11 November (afternoon): the CMC answers for the drainage, and the army may be called in to clean it
A third Daily Mirror filing the same day puts a Colombo Municipal Council official on the record for the first time, and adds a response the morning’s figures did not carry.
Deepika Wijethilake, Deputy Director of Drainage and Water Supply at the CMC, confirmed the design standard the minister gave:
“Our drainage system is designed to handle around 30mm of rain within an hour. However, last week we experienced nearly 100mm within an hour.”
The intensity of the rain and the short time it fell in is what overwhelmed the system, she said — had the same volume fallen over a longer period, the network could have managed it better. Existing capacity is simply insufficient for a downpour of that kind, the Daily Mirror reported at 2.33 p.m. on Wednesday under the byline of Sheain Fernandopulle.
What the CMC says it is doing
- Drains are cleaned daily as a routine, despite a shortage of workers
- The council plans to expand the drainage system and recruit additional workers
- Tri-Forces support is under consideration for cleaning the drainage network
The last of these is the substantive new fact. Bringing the military in to clean municipal drains has not appeared in any earlier filing this desk has reported, and it is being considered rather than decided.
The filing also records that a section of the National Hospital was inundated, affecting hospital services.
The rainfall figure is now contested four ways
This article noted on Wednesday morning that the two rainfall figures then on the record were not reconciled. A third filing has made the problem worse rather than better. The event of 6 November has now been described as:
| Figure | Period | Source |
|---|---|---|
| up to 150mm | two hours | Minister, Daily Mirror 354648 |
| 68mm | 40 minutes | CMC Commissioner A.D.S. Rohana, Daily Mirror 354680 |
| nearly 100mm | one hour | CMC Deputy Director Deepika Wijethilake, Daily Mirror 354691 |
| 129mm | ”a few hours” | Daily Mirror 354359, 7 November |
The Daily Mirror’s own headline on the third filing — “Why did Colombo go underwater in just two hours?” — does not match the quotation printed beneath it, which says within an hour. NewsFirst’s 7 November headline independently gave “over 100mm of rain in under an hour”.
These are four different officials and filings describing one storm, and no account reconciles them. The direction of the conclusion is unaffected: on every figure given, the rainfall exceeded the 30mm-an-hour standard the unupgraded 96 per cent of the network was built to, and on three of the four it exceeded the 102mm-an-hour standard of the upgraded sections too. But no single authoritative rainfall figure for 6 November exists in the reporting, and this desk has not found one.
Still open
The filing does not say how many drainage workers the CMC has or how many it is short, what the expansion would cost or cover, or who would authorise a Tri-Forces deployment. It gives no date for any of it.
It does not reconcile its own rainfall figure with the minister’s or the commissioner’s, does not say which rain gauge any figure came from, and does not address why the upgrade programme reached only 20km in twelve years — the question the morning’s filings also left unanswered.
