Tan (second from right) gives his apprentices a navigation lesson.Photo By Qian Cheng / For China Daily

Over the years, he has witnessed hundreds of accidents and garnered extensive experience in the region. He knows all the villages along the waterway and the hidden reefs and trees that lie in wait for unsuspecting mariners.

In 2008, after four years' work, he completed a guide to navigating the 348-kilometer stretch of the Mekong River from Jinghong in Yunnan to Chiang Saen in Thailand.

Since the mass shooting, Tan's squad has escorted 420 merchant ships, 116 of which needed assistance, as part of the 53 joint patrols that have been carried out by China, Laos, Myanmar and Thailand.

They have also uncovered more than 200 human trafficking cases in that time.

During his patrols, which start at Guanlei port, Yunnan, Tan not only takes charge of the ship, he coaches apprentices too.

"I hope they can steer the ship on their own next year. I feel that I need to pass on the skills I possess and help more people shoulder this noble responsibility," he said.

For many of the officers in the water police squad, Tan is a selfless coach. He spends much of his spare time giving free lectures on how to familiarize yourself with shipping passages and the skills of navigating a ship in difficult conditions. By doing so, he hopes to make the Mekong safer for all.

"Every time I pass through those waters where my 13 friends lost their lives, I cannot help thinking of them," Tan said. "But I am happy now, to see my fellow sailors working on the river in safety and able to make more money to support their families. I will give every ounce of my strength to guarantee their safe navigation."

Contact the writers at zhang_yi@chinadaily.com.cn