Wearing oversized rubber boots, Tan used a shovel to turn over knee-high grass on the dike to spot any leakage points. The patrol along the 1-kilometer dike takes 40 minutes and is conducted once every three hours.

"I used to be terrified by snakes, but I have seen so many in the past few days that I'm used to them now," said Tan.

Scorching sun, relentless rain, buzzing mosquitoes, hard bunk beds, all these make dike patrols tough. "One night, a storm blew open the tent's curtains. We were all soaked," said Tan.

"Dike patrolling is hard work. But for me, it's a daily routine, just like helping with farm work during the school holidays," Tan added.

During patrolling, Tan reflects on where his future will bring him. Having studied in computer science, he finds that the world is more than keyboards and screens.

"I see the patrols as my graduation ceremony," said Tan.