Sri Lanka, Nov. 11 -- Only around 20 kilometres of Colombo's total 469-kilometre canal and drainage network have been upgraded since 2014 to cope with heavy rainfall, according to Cabinet Spokesman and Minister Dr. Nalinda Jayatissa.

Recent flooding in several parts of Colombo was mainly caused by exceptionally heavy rainfall, with between 129mm and 150mm of rain falling within one to two hours, while Colombo's existing drainage network was designed to accommodate rainfall of around 30mm per hour, the Minister stated while speaking at the weekly Cabinet decisions media briefing.

Only around 20 kilometres of the city's total 469-kilometre network have been upgraded since 2014 to withstand rainfall intensities of up to 102mm per hour, whi...