1. The layout of drainage pipes in residential quarters should be determined according to the principle of short drainage flow direction and small buried depth of pipes, and the drainage flow direction should be determined as far as possible.

2. The control in this article is mainly controlled by pipe diameter and drainage slope, and the spacing between inspection wells should not exceed 30m. When the diameter of outdoor domestic drainage pipeline is less than or equal to 150mm, the spacing of inspection wells should not be greater than 20m, and when the diameter is greater than or equal to 200mm, the spacing of inspection wells should not be greater than 30m.

Specific specifications can be found in GB500 15-2003 Code for Design of Water Supply and Drainage in Buildings.

Baidu library should have some specifications.

Supplement: There is no clear stipulation in the specification, but the minimum restrictions are made on the pipe diameter and slope used.

Minimum diameter, minimum design slope and maximum value of domestic drainage pipe in residential area

The design fullness shall be determined according to the table.

Buried plastic pipe: the minimum pipe diameter is 200 and the minimum slope is 0.004.

Concrete pipe: the minimum pipe diameter is 300 and the minimum slope is 0.003.

The maximum design fullness of both is 0.55.

The diameter of the injection pipe shall not be less than that of the building discharge pipe.

In other words, the design code allows a distance of 200 meters, but the pipe diameter and slope should be designed well, and there is a maximum fullness limit to ensure the smooth flow of this pipeline. In addition, the spacing between inspection wells is less than 30 meters, which is convenient for plugging and dredging.

Furthermore, the design should calculate the design flow according to the use function to ensure that the drainage requirements are met.