The unprecedented rain and flooding on Saturday, April 1st, across the nation’s capital, Port Moresby, was discussed internally at the National Capital District Commission (NCDC).
City Manager, Ravu Frank and the NCDC engineers, made a quick catchment analysis for the possible causes of the flood and several reasons was found to be the cause of the flooding.
The meeting also included the consultancy of a Papua New Guinean hydrology expert based in Brisbane, he advised that the downpour occurred over two hours in high intensity, therefore the impact was massive and unprecedented.
He stated that there was no well-designed drainage system that would have stood that volume of water, the pit openings could not capture the amount of surface flow that Port Moresby experienced, and there was too much flow. Other reasons was the climate change effect, rainfall intensities are getting higher.
Other causes include poor community behaviours, sanitation and hygiene causing blockages to the drainage system. Fridges, washing machines, tyres and other household items were found in the culverts, and large amounts of waste, silt, buai husks and plastics were found to be thrown into the drains including uncollected wastes.
The National Weather Forecaster, Peter Waupi confirmed yesterday the intensity of the rain was the main reason for the flooding.
“Saturday evening’s rainfall data was 145.8mm over 3 hours. It was above the average rainfall data. He also said April is the month for monsoon rains, which will continue in the next 2 or 3 days,” said Waupi.
The average rainfall in the entire wettest month of March is between 190 - 233 mm. Rainfall in one day with 145.8mm rain equals one month of rain just fell in 3 hours yesterday.
City experienced flash floods everywhere, but the most affected areas were Jackson’s Airport, Hohola, 8-mile and Malolo estate. These housing estates had poor drainage system due to the digging of the mountain at the back by developers respectively.
The poor hygiene practiced by communities didn’t also help.
Frank said he will engage experts to do the hydrology, audit the drainage network, develop and propose solutions. He said NCDC will take immediate action to rectify the situation.
“In the meantime, we have scaled up the cleaning and unblocking of the drains. We also assure everyone that we identified 26 drainage hotspots in the city; we have been fixing the problem at Hohola, and we will also work with NAC to resolve the issue of the collapsed bridge at the airport.
“We will get the developers at 8-mile including Malolo Estate, to address the problems there too.” assured Frank.
Frank also added that they will simultaneously start work on another three locations out of the 26 hotspots, as soon the notice period to those who encroached on the drainage reserves are demolished.
NCDC would like to remind its city residents to exercise caution when driving on wet roads and carefully or refrain from driving through flood water. Plan your journey ahead of time. Allow extra travel time and adhere to all signs.