The work was so far ahead of schedule that filling the dam embankment with earth, the activity most susceptible to damage from rain, came up just before the beginning of the rainy season.
填壩就是將水壩中心灌滿混凝土，完成後才能繼續做表面的土石工程。填壩時最忌下雨，因為雨水會將未乾的混凝土沖走，除了功虧一簣外，還可能造成災害。因此印方不贊成他們在雨季將臨前填壩。