A well point is a pipe with wall openings big enough to allow water to enter and small enough in order to keep the water-bearing formation in place. They are suitable for hand driving and available in different sizes from 1 1/4 to 2 inches in diameter while from 19 inches to 3 feet long. A Well point Cape Town consists basically of a series of diligently spaced small diameter water abstraction points connected by a manifold, to the suction side of an appropriate pump. Why Well Points are Used They are required to develop a water supply for gardens, sprinkling lawns, etc. Well points are also used to obtain an economical supply from a shallow aquifer. The water table must be high, if possible within 10 feet but no farther than 15 feet underground. In addition to this, the well point should be driven deep enough to enter a water-bearing formation below the water table, and should not exceed 25 feet in depth. Furthermore, shallow water tables are prone to pollution and things like drain fields, animal wastes, dry wells, heavy fertilizer application can contaminate this table. Recharge is frequently from rainfall, and falling directly above and permeating downward to the water table. The water may carry contaminants as it moves downward it. Therefore, care and regular testing are necessary if you are using the water for drinking. Types of Well Point The well points are important components of every installation. There are mainly two types of well points- 1) Single Stage Well Point and 2) Multistage WellPoint. Single Stage WellPoint A single well point consists of a pipe about 1 m long and 50 mm in diameter and has perforations covered with a screen to prevent clogging in. A jetting nozzle is given at the lower end and it acts as a drive point. Apart from this, a ball valve provided at the lower end which allows the water to flow in a downward direction only during installation. A riser pipe, also known as a vertical pipe in a building have the same diameter as the well point connects the well point at the bottom end. These pipes are connected to a horizontal pipe at the ground level and this pipe connected to a pumping unit. Also, the well points are installed to the necessary depth by jetting water through vertical pipes in the downward direction. Pumping is started for the excavation once installed. Multistage WellPoint Multistage Well Point s is used if excavation exceeds 4.5 m and is installed in stages. For example- In the first stage, Multistage Well Point s are installed to a 4.5 depth and put into action till the water table is lowered by 4.5 m. After that, the area is excavated up to this 4.5 m depth. The second stages of well points are installed after this within this already excavated area. After that, the water table is lowered by another 4.5 m. Read more: Borehole: A Great Alternative If You Have Poor Water
1 Comment
10/6/2023 05:48:44 pm
The well point is connected at its bottom end by a riser pipe that has the same diameter as the well point. At the ground level, a horizontal pipe called a header pipe connects the riser pipes. A pumping unit is joined to the header pipe. The well points are put to the desired depth by jetting water through riser pipes in a downward manner. The well points are separated every 0.6 to 1.5. Pumping is initiated after installation and continues until all excavation work is done.
Reply
Leave a Reply. |