Windhoek: Jinan, the capital of east China’s Shandong Province, famously known as the “City of Springs,” has integrated advanced technologies in its subway construction efforts to protect its renowned natural springs.
According to Namibia Press Agency, in addition to the three existing subway lines situated far from sensitive spring areas, Lines 4 and 8 are in trial operation, with three more lines under construction. Research indicates that Jinan’s springs originate from the southern mountains, where precipitation penetrates the ground and moves northward, creating approximately 1,000 springs, including the notable Baotu Spring.
To safeguard these springs, the Shandong Provincial Bureau of Geology and Mineral Resources developed high-precision geological survey technology to map underground water channels. Zhao Zhiqiang, chief engineer, compared the technology to an “ultrasound scan” for karst groundwater channels, which has laid the groundwork for spring water flow protection.
During the planning of rail transit lines, workers monitored the highest water levels of springs in sensitive areas. Rail lines and stations were designed to maintain a buffer distance of two to three meters above these levels. Subway Line 4, which is close to Baotu Spring, employs a groundwater diversion system using a “U-shaped pipe” to redirect water without obstructing its flow.
The team also devised technical measures to minimize construction impact on the springs, such as redirecting subway lines from water-sensitive areas and reducing tunnel depth. These measures have been applied to several subway projects in Jinan.
Zhang Yunfeng, head of the team, stated that their comprehensive protection strategy has enabled Baotu Spring to maintain a continuous flow for 22 years, proving that modern infrastructure can coexist with natural springs. Sources at Baotu Spring reported that the spring’s water level reached 30.29 meters, the highest since 1966, owing to rainfall since late September.
Furthermore, the team developed a groundwater monitoring platform for spring protection across 213 locations, a first in north China. Ma Hekuan, platform manager, described the system as a smart monitor for springs, providing real-time data on water levels, quality, extraction, and replenishment, and offering early warnings for water level changes.
“The monitoring system acts like a ‘CT scan,’ transforming groundwater management from guesswork to data-driven precision,” Ma explained.