Chongqing Baiheliang Underwater Museum uses scientific and technological means to ensure the safety of cultural relics
Millennium inscription, reproduced underwater
Ride the 91-meter-long tunnel-type escalator gradually into the water, cross the 146-meter horizontal corridor, and walk through the 40-meter-deep visiting corridor under the Yangtze River. This is the Chongqing Baiheliang Underwater Museum located in the middle of the Yangtze River. .
The original site of Baiheliang is a natural stone beam with a length of 1600 meters and an average width of about 15 meters. It is located at the intersection of the Yangtze River and the Wujiang River in the north of Fuling City.
There are 165 inscriptions on the beam, which record the hydrological data of the dry years of the Yangtze River for more than 1,200 years since the Tang Dynasty and the original poems of a large number of historical celebrities.
Through 23 circular glass observation windows, you can clearly see the thousand-year-old inscriptions and stone fish left by the ancients on Baiheliang.
From the ancient hydrological station to the underwater museum, how was it built?
After the Three Gorges Dam was impounded for 175 meters, in order to prevent the Baiheliang inscription from being submerged at the bottom of the river, the Baiheliang inscription protection project was launched in 2003, using the principle of "non-pressure container" to protect the original appearance of the inscription.
How to create a good visiting experience for the audience?
The difficulty lies in the "water".
The clear water body is the premise for tourists to see the inscriptions of Baiheliang directly from the observation window.
Purifying water has become the focus of this underwater museum.
At the entrance of the visiting corridor of the Baiheliang Underwater Museum, two professionally qualified divers are preparing for the water. The temperature is low underwater, so they need to wear warm clothes in the diving suit and increase the waist. Counterweight to control buoyancy in the water.
After strictly checking the air-tightness of the diving gear, the diver jumped into the diving cabin.
"Every 3 months of operation, there will be problems such as poor transparency of the water body in the protection body, algal blooms and the growth of biofilms on the surface of the inscriptions, so professional divers need to dive and clean regularly." said Yang Bangde, director of the Baiheliang Underwater Museum in Chongqing.
The diver swims back and forth in the closed glass cover, while opening the sewage valve, and using the sewage hose to remove the sediment in the protected body by the pressure difference between the inside and outside of the water.
On the other side, wipe the algae on the observation window and lighting with a towel.
The deeper the water and the greater the water pressure, the more difficult it is to work underwater.
Therefore, under normal circumstances, each underwater work does not exceed 1 hour, and the next underwater work can only be carried out after 24 hours.
"The temperature and material of underwater lighting fixtures will affect the water quality." To this end, Yang Bangde led the team to continuously update the deepwater lighting system.
The materials of the lamps are changed from aluminum lamps to stainless steel lamps, so as to reduce the analytes produced by long-term immersion of aluminum lamps in deep water; lamp beads are changed from warm white light beads to cool white light, which effectively reduces the temperature of the water, so as to slow down the Growth rate of algae.
Coupled with the 24-hour uninterrupted circulation system filtration and other methods, "the water in the hood today is of a higher standard than drinkable mineral water in terms of turbidity." Yang Bangde said.
"Stone fish come out of water, and it is a folk proverb passed down from generation to generation in Fuling area with a mega-year of prosperity," said Yang Bangde.
Through the glass window, following the direction of Yang Bangde's finger, you can clearly identify the double carp stone fish inscription on the beam wall.
More than 1,200 years ago, local people came to a rule by observing the water level of the Yangtze River. Once the stone fish inscription appeared on the water surface, it means that the dry water cycle has passed, the harvest year is approaching, and the next year will be full of rain and harvest.
In Yang Bangde's eyes, the inscription on Baiheliang is such a book that is hidden underwater and records a thousand-year history.
Our reporter Wang Xinyue