However, the International Red Cross said floods and landslides have claimed at least 53 lives over the past three days in the Terai region, bordering India, and other areas of Nepal.
Monsoon floods and landslides have killed at least 66 people across Nepal and India but officials fear that figure could nearly double as rescuers search for dozens believed lost under mud and in submerged villages.
Home Minister Janardan Sharma said hi-level talks are on between the two countries to open all the gates.
The country's home ministry said on Sunday that the death toll had risen to 49, with 17 people injured and thousands left homeless.
As many as 8,300 security personnel from Nepal Police, Armed Police Force and Nepal Army have already been mobilised in the rescue operation across the country.
Similarly, rescue works were ongoing at Madargachhi, Kapan, Kawas, Salpara, Saurghutu of Jhapa and Budhikhola of Sunsari, Hanumannagar and Tilathi of Saptari, Bagmati area of Sarlahi and Rautahat by using the rafting boats.
But dozens were still missing somewhere at the bottom of the ravine, with soldiers and rescuers clawing through the mud and rock to reach them.
Families perched on trees with young children overnight as floodwaters swept away homes in a village in southern district of Chitwan, local media reported.
Several hotels in Sauraha, in Chitwan district, have been inundated, trapping the tourists, many of them foreigners.
"There isn't a house without water".
Those rescued and evacuated have been sheltered at schools and other facilities, while the District Disaster Relief Committee has made arrangements for providing food to them.
Hundreds of houses have been submerged in Morang.
Prime Minister Sher Bahadur Deuba expressed his condolences and urged people to remain.
"I have already instructed authorities concerned to rescue flood victims, move them to safer locations and immediately provide relief to them", he said.
The latest casualties bring the death toll from this year's monsoon season to more than 100, government records show.
The monsoon season, which starts in June and ends in September, causes big floods in Nepal each year.