The Water Festival this year falls on November 7-9. But with Cambodia set to host the ASEAN summit and related meetings in the same week this month, the festival are not being celebrated in Phnom Penh, though some provinces have been holding celebrations since October.

Known locally as Bon Om Touk, the festival takes place in late October or early November to mark the end of the monsoon season as well as the change in flow of the Tonle Sap River.

The second day of the festival aligns with the date of the full moon on the Khmer lunar calendar month of Katdoek (or Kartika in Sanskrit), which is said to be when the long-cycle rice crop is ready for harvest.

The festival usually features dragon longboat races on its first day. Royal boat races have been held in Cambodia since at least the time of King Jayavarman VII to celebrate the victory of the Khmer navy over Cham invaders from the Champa kingdom in a large boat battle on the Tonle Sap Lake.

During the Longvek period of the 16th and 17th centuries, King Ang Chan I appointed Ponhea Yat as the “earth-guardian” in Kampuchea Krom’s Bassac district and he organised the navy into three groups to defend the region from invasion by the Da Viet kingdom under ruler Mac Dang Dung.

After his forces were victorious, King Ang Chan I celebrated with a lantern lighting ceremony that still takes place after the boat races each year.

Originally, there were only three types of boats that participated in the races: large motorless freight barges, the oum boats and chaev boats. The three types of boats each have men’s and women's teams.

However, in recent years, the National Committee for Organising National and International Festivals has allowed foreign boats to participate in the race.

A short boat has 20 to 30 crew members and a long boat has 40 to 50 crew members typically but sometimes up to 70.

Most of the participants in the past have been from river adjacent provinces such as Phnom Penh, Kandal, Kampong Cham, Kratie, Prey Veng, Stung Treng and so forth and they still enter the largest number of boats, but today boats enter the races that come from every province, even those without major rivers or lakes.

Crew members must be strong enough to row and need to know how to swim should any accidents occur, though there are rescue crews on standby to fish people out of the water.

This year, organised boat races have been held in Kandal, Prey Veng, Svay Rieng, Kampong Cham, Pursat, Takeo, Kampot, Kampong Thom and Siem Reap provinces.