Q4-2 Water comes out of the hole in the retaining wall next to it. What's going to do?

It is called a "water drain hole" provided to prevent excessive force on the retaining wall when rainwater penetrates into the ground, and plays a very important role in the safety of retaining walls ( Please note that technical standards for residential land development).

Part of the guide on this answer

• About drain hole of retaining wall
  "Guide to Residential Land Development", Part 3, Chapter 3, Section 1, 4 (PDF: 415KB)
• About technical standard of construction about residential land development
  "Guide to Residential Land Development", Part 1, Chapter 2, 5 (PDF: 307KB)

Contact for inquiries regarding this answer

• About permission of construction about residential land development
  Housing and Architecture Bureau Residential Land Examination Department

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