- How water enters the well
- Determine the reason for poor admission
- Deepen or move
- Well inspection and cleaning
- Replacing the bottom filter
The hotter the summer, the higher the likelihood of encountering a lack of water for household needs. What is the reason for the loss of water from the well: low rainfall or poor flow? Today we will teach you how to correctly determine the cause of the fall of the well mirror and eliminate it yourself..
How water enters the well
Determining the geomorphological features of a particular area is a primary task for a full understanding of how a well works. Both neighbors and specialized teams developing water sources in the adjacent territory can shed light on this issue..
In general, the situation looks like this: alternating layers of sedimentary rocks begin under the layer of chernozem. Clay is interspersed with sandy deposits, a so-called aquifer is formed on the surface of each water-resistant layer. The relief of these formations is very bizarre and can change quite quickly over time..
Layout of aquifers: 1 – top soil layer; 2 – loam; 3 – sand; 4 – top water; 5 – bottom filter; 6 – well; 7 – interstratal aquifer; 8 – clay; 9 – artesian aquifer
When digging a well, they try to “catch” the second or third water carrier from the surface: they pass a sand cushion, and, almost reaching the next layer of clay, form the bottom of the well at this level and arrange a bottom filter. It is through the bottom and the filter that up to 95% of the water enters the well. A small amount of it can seep along the walls from the layers located above through the joints in the rings, but they try to avoid such phenomena..
The variability of the geomorphological setting is the main reason for the sudden drainage of wells. Water carriers are best thought of as underground rivers, because a fold of a clayey water-resistant layer forms a channel with a certain width, depth and water level. Like surface rivers, these rivers can experience periods of flood and drought..
Determine the reason for poor admission
As a rule, a complete or almost complete drop in the static level of the well is associated with the depletion of the water carrier. This can occur both due to shifts in the water-resistant layer, and be the result of land reclamation in neighboring agricultural enterprises..
For the most part, water carriers are depleted once and water no longer appears in them. It happens suddenly: after the next spring flood, the bottom remains dry. A way out of this situation can be deepening the well with the achievement of a deeper water carrier or transferring it to another place if the water-resistant layer has a significant slope.
A more trivial reason for the loss of water from a well is a clogged bottom filter. It is arranged so that the incoming water does not deposit fine sand and salt from the permeable layer, but the smallest particles can clog the gravel bed and the flow of water stops or slows down significantly. In this case, the depletion of the well occurs gradually, from year to year the water in it becomes less and less..
It is worth mentioning that a sudden loss of water from the well can happen due to the “miss” of the diggers. If the bottom ring is located too close to the waterproof layer, it can sag over time and the well will clog itself. You can verify this defect by drilling a number of holes in the ring at the very bottom at several points around the circumference, and then going up 1-1.5 meters, making rows of holes every 15-20 cm. If after a while water does not appear – water carrier is definitely depleted.
Deepen or move
Deepening a well is always easier and cheaper than building a new one. Sometimes half a dozen rings are enough to break through to the underlying water carrier – the main thing is that it.
You can verify the presence of such by measuring the depth of wells in neighboring areas. If the water mirror has a drop of more than two meters – there is another aquifer and a deepening of the well below – a completely justified idea.
Please note that the decision to move the well is almost always accompanied by dismantling and backfilling of the old one. Therefore, even if the deepening is not successful, you only risk the diggers’ time. All rings used for deepening and part of the surviving old ones can be pulled out and used in the construction of a new well.
The question remains: where can the well be moved? If initially he dug into 3-4 aquifer, it is highly likely that there is still water at higher layers and in this case a new well can be dug near the old.
Geological exploration at the site will bring more clarity. With the help of a hand drill, you can independently investigate the location of the soil in several places, while a special examination will give a comprehensive report on the position and direction of underground rivers.
Sometimes the drainage of the well is accompanied by a steep subsidence of the channel, and at the same time it is necessary to move along the slope of the waterproof layer. In this case, it is possible to enter the water of the former aquifer, but in a different place of the site.
Well inspection and cleaning
Determining if the bottom filter is dirty is easy. The remaining water is pumped out of the well, and then a shallow well is punched in the center. As a rule, along the open path, the flow of water increases before our eyes and then the bottom filter is cleaned thoroughly and a new one is filled in..
But first you need to make sure that the residual water inflow does not come from the overlying horizons. To do this, you will have to go down into the well personally and carefully examine the walls for leaks. If the rings are displaced, and there is no way to close the gaps, the well can hardly be considered suitable for further intake of drinking water.
It is convenient to remove the bottom filter using a hand bucket: 30–40 cm of a large pipe section, one edge of which is cut at an angle of 30–35 °, and two cables are fixed 50–70 mm from the edges. This bucket is thrown with the sharp end down so that it fits snugly into the bottom, and then pulled out by the front cable, extracting the slurry in several passes.
Thus, only the center of the bottom deepens. The edges are then loosened with a rope crowbar and the remaining filter removed again. It often makes sense to shake up the fine slurry using a pump with a short piece of hose pointing downwards and pump out the water with the increased pressure of impurities several times..
When removing the filter, it is very important to stop in time without deepening the bottom too much. Each time you remove the bucket, you need to control the nature of the dirt in it. The presence of dense clay lumps is the first sign that the bottom is properly cleaned, or filter residues are only at the edges.
Replacing the bottom filter
After cleaning from the well, it is necessary to completely pump out the water several times, preferably after one of the drainages, go down and examine the bottom. Before installing a new bottom filter, the question of its need should be raised. For example, if the bottom is formed by dense clay and water comes out of it under a slight pressure, it is not recommended to fill.
The simplest bottom filter is made of crushed gravel or quartzite of 12-15 mm fraction. Granite crushed stone is not used due to its high toxicity, and stones should not be collected from road embankments and at the bases of power transmission lines.
Sometimes, in order to better purify water, they arrange complex filters containing several layers with materials of different fractions. With a loose clay bottom of the well, the layers are poured in such an order that the smallest fraction is at the bottom, and the largest at the top. If the bottom of the well goes straight into the sandy quicksand, the filter is poured in the opposite order..
1 – river pebbles; 2 – gravel; 3 – quartz sand; 4 – concrete rings
It is recommended to use washed quartz sand of 2.5–4 mm fraction as a fine fraction. The middle layer is arranged with ordinary gravel 15–20 mm, the largest – of river pebbles 50–80 mm in size. Sometimes a small amount of shungite or jadeite is poured between the middle and large layer of the bottom filter – these minerals well cleanse water from toxic substances, soften it and improve organoleptic qualities.