The description of the river is complicated by the local naming convention: instead of using the name Kelantan river from estuary to source, the name is only used for the section from the estuary to the confluence of its two main tributaries, the Galas River and the Lebir River, near the town of Kuala Krai. The same naming convention applies to these tributaries. Thus to describe the main river from source to mouth involves four names: the River Betis, then the River Nenggiri, then the River Galas, and finally the Kelantan River.
Route
The river tributaries rise in the forested mountains in Gua Musang region in southern Kelantan, where many Orang Asli tribes live. The area is known for its limestone outcrops and caves. Along the River Nenggeri section some cave systems show evidence of habitation going back to 9000 years ago, such as Gua Cha near Kuala Betis. Lower down, Malay villages dot the banks of the river which passes through one of the most densely populatedflood plains on the Malay Peninsula whose padi fields produce around 12% of Malaysian rice production. The river flows past seven important towns, from south to north: Kuala Krai, Tanah Merah, Machang, Pasir Mas, Tumpat, the state capitalKota Bharu, as well as Pengkalan Chepa, which lies near the mouth of the river. Towards the estuary there are several islands in the river. The area around the actual estuary, known as Kuala Besar, is dotted with picturesque fishing villages, which are also well known for the production of batik for which the State of Kelantan is famous. The mouth of the Kelantan River is also notable for being the site where Japanese troops first landed during their invasion of Malaya in December 1941.
Flooding
The Kelantan River regularly overspills its banks during the months of November to February because of the northeast monsoon season. The estimate flood volume under the 50 year flood condition at Kusial Bridge is about 6 billion m3. Severe flooding occurred in 1926 and 1967. In the 1967 floods 84% of the Kelantan population were badly affected. Some 125,000 people were evacuated and 38 drowned. More recently a telemetric flood forecasting system has been installed to give warning of high river levels. Some of the worst floods in recent years have been:
