In Japan, the Mj7.6 Noto Peninsula Earthquake occurred on January 1, 2024, causing severe damage over a wide area. In mountainous areas, natural slopes slid and road embankments collapsed in many places, cutting off traffic and leaving 3,345 people stranded in 24 districts, creating a critical situation. In the plains, liquefaction occurred in many residential areas, causing severe damage to houses, lifelines, and roads. This liquefaction caused the lateral flow of gently sloping ground at the inland edge of sand dunes. From Uchinada Town to Kahoku City, lateral flow of up to 2 to 3 meters occurred in various places over an area of about 10 km x 0.1 km, causing serious damage to low-rise houses, roads and lifelines. Not only did the low-rise houses settle and tilt, but they were also pushed or pulled horizontally and distorted so much that they had to be demolished. The road curved horizontally due to lateral flow and rose by up to 1 meter at the end of the flow. In Japan, during the 2011 Tohoku Earthquake, liquefaction occurred in the Tohoku region of northeastern Japan and in the Kanto region surrounding Tokyo, and about 27,000 low-rise houses were damaged due to liquefaction. After the Tohoku Earthquake, a new project to protect residential areas against liquefaction was established in Japan. Ten cities affected by the 2024 Noto Peninsula Earthquake have also begun to consider the possibility of using this project to lower groundwater levels over a wide area as a countermeasure, and soil investigations have been carried out since six months after the earthquake. However, in areas where liquefaction-induced ground flow occurred on gently sloping ground, new problems have arisen, such as how to avoid blocking the flow of groundwater.