Reverse back to have a look, the scenarios at Bukit Lalang Village, Tikam Batu during flood time. It was October, 2003. Where the big flood (second time happened after year 2002) waves attacks almost lower part of nothern area of Malaysia.
The Kuala Muda-Yan district in Kedah and Nothern Seberang Perai in Penang badly influenced by the big flood.
The heavy rain kept falling down from the monsoon clouds.
Wherereas on the other hands, the waters from upstreams of Muda rivers was coming down to downstream, the waters level rose immediately, from the river went to the cannals sytem, from the cannals to the drain system, from the drain to the paddy field, from the paddy field rose up to housing area.... that was the mechanism
"Flood indicator - already reached half-heighted phone booth"