Core Viewpoint - The construction of the Jinan Metro lines is facing challenges due to the need to protect the city's abundant underground springs while ensuring the metro's operational efficiency [2][3][4]. Group 1: Metro Construction and Environmental Impact - Jinan, known as the "Spring City," has over 1,000 springs, making the integration of metro construction with spring protection a primary challenge [2]. - The Shandong Provincial Geological Bureau's 801 Team has conducted preliminary investigations and environmental impact assessments for the metro lines, addressing critical questions about suitable construction areas and potential impacts on spring water [2][3]. Group 2: Advanced Geological Survey Techniques - The 801 Team proposed high-precision geological survey techniques to accurately map the underground spring networks, akin to a detailed ultrasound of the water flow channels [3]. - During the planning of metro routes and stations, monitoring of sensitive spring water levels is essential, ensuring that construction does not exceed a safe distance of 2 to 3 meters from the highest water levels [3]. Group 3: Innovative Water Management Technologies - The team has implemented groundwater diversion technology during the construction of the metro, allowing underground water to flow around the metro tunnels using a "U-shaped pipe" principle [3]. - Techniques such as "original water, original position, same layer, same quality, same quantity" are employed to maintain groundwater levels within ±10 cm [3]. Group 4: Long-term Spring Protection Strategies - The 801 Team has developed a spring protection model focusing on "regulating, storing, supplementing sources, and conserving" to ensure the sustainability of the Baotu Spring for over 22 years [4]. - A self-developed groundwater monitoring platform integrates 213 monitoring points, enabling early warnings of water level fluctuations and visualizing groundwater movement [4].