Planning and arrangement of vertical well drainage

Reasonable well depth and well structure

In order for the wells to play the role of irrigation, flood control, prevention of stains, alkali modification, prevention of secondary salinization of the soil and desalination of groundwater, each well must have a large water output. In order to increase the infiltration of rainfall and irrigation water, improve the efficiency of salt compression, and form a certain groundwater reservoir in the surface layer, while ensuring that the wells are able to pump a larger volume of water from the aquifer, there should be a greater depth of descent of the submersible level. For this reason, in the planning and design of water wells must be based on the different hydrogeological conditions around the selection of reasonable well depth and well structure.

1) In the shallow layer of good sand layer or no good sand layer, but the soil permeability is good (such as fissure clay, etc.) in the case of shallow machine wells or vacuum wells, the well pipe from the top to the bottom of all the use of water filtration pipe, in this case, generally can guarantee a certain amount of water and diving level drop depth.

2) sand layer buried in a certain depth below the surface, but the sand layer VA t-_ no obvious water barrier, in order to make a single well to maintain a certain amount of water, water wells can be drilled to the water-bearing sand layer, pumping, although some of the water from the lower sand layer, but because the upper soil layer has no obvious water barrier, large-scale pumping dive can be reduced, so you can ensure the formation of a certain amount of diving depth and shallow underground reservoir. level drop depth and shallow underground reservoir capacity, is conducive to withstand the upper water, promote soil desalination and desalination of groundwater.

3) When the upper soil layer has poor water permeability and there is no good sand layer at a considerable depth, in order to ensure that the water wells have a larger water output and a greater depth of descent of the water table, it is necessary to select the appropriate well structure, such as large wells, large aggregate wells, radial wells, plum blossom wells (group of wells) and horizontal tube wells and so on.

Planning layout of wells

Wells with drainage tasks, the planning layout should depend on the natural characteristics of the region, water conditions and the task of the wells. In the surface water irrigation water source and the implementation of the combination of wells and canals in the region, the task of well irrigation and well drainage is to ensure that the irrigation water, control the water table, flood control and prevention of flooding, and to prevent secondary salinization of the soil. In this case, the spacing of wells on the one hand, determined by the water output of a single well can control the irrigation area, on the other hand, also determined by a single well to control the groundwater level requirements. In areas where vertical wells are utilized for simple drainage, the spacing of the wells is determined primarily by the requirement to control the water table.

Shafts in the plane generally more equilateral triangle or square arrangement. By the effective control area of a single well can be obtained from the effective control radius of a single well R and well spacing L. Wells and canals should be arranged in conjunction with the irrigation canal system.