PETALING JAYA: The Drainage and Irrigation Department (DID) will further improve its existing flood forecasting and early warning system to better manage future episodes of heavy rain.
Its Water Resources and Hydrology division director Datuk Hanapi Mohamad Noor said the department hopes to collaborate with the Malaysian Meteorological Department (MMD) and get experts to develop tools with high resolution software as well as train staff to quantify rainfall based on radar data.
Hanapi said the proposed project would develop software and a forecasting model using real time radar images of rain clouds accumulated in 24 hours in order to arrive at the total one-day rainfall forecast.
“From the data, we can forecast one to two days ahead the water level at the downstream of bigger catchment areas such as for Sg Johor, Sg Pahang, Sg Kelantan and Sg Sarawak,” he said in an interview.
For smaller catchment areas such as Sg Kelang and Sg Damansara, flooding could be forecast a few hours ahead, he added.
Hanapi was asked if the DID could have predicted the severe floods that hit Terengganu, Pahang, Kelantan, Johor, Sabah and Sarawak last month, which resulted in nearly 90,000 people needing evacuation besides millions of ringgit in damage.
Hanapi said the DID currently did not have the expertise for detailed forecasts, while MMD could forecast rain only in general terms, such as under its current colour coded (yellow, orange or red) weather warning system, but could not quantify the amount of rainfall before it rains.
The present forecasting system was based on input from the DID’s telemetry stations that measure water levels, but this gives little time for warning and evacuation.
Hanapi said the DID would be asking for an allocation amounting to RM2mil from the Government for the project.
Hanapi said that on Dec 3, Kemaman in Terengganu received 777mm of rainfall, and Kuantan in Pahang 541mm, both the highest rainfall ever recorded in those towns since the 1970s.
At the Jabur station of Kemaman, the highest amount of daily rainfall before this was 607mm, which occurred on Feb 13, 2001.
For Kuantan, the highest amount of rain per day before this was 256mm, which occurred on Dec 11, 2004.
“This is extraordinary,” said Hanapi, who added that flood mitigation projects such as the construction of bunds for Sg Kisap, Kuantan, completed in 2010, was meant to cater for rainfall intensity of 380mm per day.
Hanapi acknowledged that the DID and other relevant authorities also needed to improve on the dissemination of flood warnings.
He believed that many could have missed the warnings as they might not have access to the Internet, television or short message services.
In Kuantan, for instance, electricity was cut off for a few days after dozens of Tenaga Nasional’s substations there were inundated. In total, more than 1,000 substations nationwide were damaged by flooding last December.