KATHMANDU: With monsoon gaining momentum, the Flood Forecasting Section of the Department of Hydrology and Meteorology alerted people against possibility of sudden rise of water level and flash floods in a few small streams of provinces 1,3,5 and Gandaki Province on Saturday morning. According to a flood forecast bulletin issued by the FFS, the water bodies of Ilam, Taplejung, Panchthar, Dhankuta, Bhojpur, Kavre, Sindhuli, Gorkha, Lamjung, Kaski, Syangja and Rukum are likely to witness flash floods. The water level in small rivers originating from Chure Range and the Tarai in provinces 1, 2 and 3 is expected to rise. The water level in the Koshi, Karnali, Narayani, Mahakali, Kankai, West Rapti and Babai rivers is below the red mark.