CHONGQING (CQNWES) -- Recently, a large area of hollow stones appeared on the river beach under Youting Square in Nanbin Road, Chongqing. These stones look like “Tetris” and have attracted a great number of visitors.

What are these rocks? Why did they appear on the river beach? The reporter recently learned that these stones are ecological fish nest bricks designed by Chongqing Shipping Engineering Survey and Design Institute of the Yangtze River.

According to the staff of Chongqing Shipping Engineering Survey and Design Institute of the Yangtze River, the ecological fish nest brick, with a side length of 0.9 meters and a thickness of 0.25 meters, weighs about 920kg. For one thing, these stones protect the original riverbed from deformation caused by water erosion; for another, they raise adhesion of micro-organisms living in the riverbed, maintain the water connectivity, and offer favorable environments for aquatic animals to live and forge.

“In fact, next to these hollow stones, there is another kind of solid stone.” The staff said, solid stones resemble the twisted Chinese character “王 (wang)”, so they are also called “twisted Wang concrete blocks”. The blocks feature good friction and strong ability to resist wind and water, which contribute to the stability of the building structure. The weight of a single concrete stone is about 800kg.

These stones were submerged in the river, and they came into sight because of the low water level recently. The relevant staff reminded the public to be careful when coming to view these stones along the riverside. (Translated by Cai Xinyu, Fathom Language Limited)