Physicist and astronomer Stefan Feeney of University College London, one of the...
A well on the site is an opportunity to use natural water free of chlorine and other impurities chemical substances. It can serve as the main or additional source of water consumption. Many landowners have encountered a situation where there is little water in the well. The cause of fluid leakage may be drought, errors in the installation of the structure, or other factors. The problem can be solved independently, the main thing is to find out its cause and the procedure for restoring the well.
Types of wells
Local sources in the areas have the following classification:
- Accumulative - the period of filling after complete drainage is about 10 days. Slow recovery of the level is a distinctive feature of such sources. Their aquifer has a small head. Filling occurs through the walls and bottom of the shaft.
Information. The height of the water column of the storage well reaches 3-7 rings, 90-100 cm in size.
- Key - concrete rings mines are installed directly above the key beating from the soil. The well fills up quickly, but has a limited debit. Its filling after complete emptying takes from several hours to 2 days. The reason for the decrease in fluid flow is contamination or the ingress of foreign objects into the mouth of the key.
- River - the source is characterized by a significant depth, reaching the level of an underground river. It reliably serves the owners, fills up quickly, has a large debit. If the water has left the well, it means that the river has changed its course. In such a situation, one way out is to dig a new well.
Types of wells
Reasons for leaving water
The water level in the well is not constant, but in some cases it drops catastrophically. What factors influence its value:
Natural
- seasonal fluctuation in the amount of liquid (summer drought);
- change in the course of an underground river;
- the natural composition of the soil.
constructive
- depressurization of the joints of the rings;
- installation errors;
- technical defects that appeared in the source shaft;
- bottom silting.
The influence of temporary natural factors explains the low water level in the well at certain seasonal intervals: the end of summer or winter. This is due to the long absence of precipitation. Usually, all owners of autonomous sources find themselves in such a situation. To exclude other options, it is enough to find out about the state of the water supply from the neighbors.
Attention. Springs dug to the depth of the first water horizon regularly experience a seasonal shortage of filling.
Low water level
There is nothing to be done about the seasonal lack of precipitation, leading to the drying up of water. We'll have to be patient and wait for the natural return of the liquid after the rains. In order not to find yourself in a similar situation, you should listen to the advice of experts on the optimal time for building a well. Drilling should not take place during the season high water(autumn, spring), otherwise it will stop at a time horizon that disappears with the onset of drought.
Underground stream that feeds autonomous well, may disappear (change direction) as a result of movements earth's crust. This process is not noticeable, so it remains only to assume its influence.
Another reason why the well is left without water is the appearance of a powerful productive well nearby. It takes the bulk of the liquid, significantly reducing the debit of small sources.
Dry well - equipment errors
The most common reason for the loss of productivity of a personal well is siltation of the bottom. Through it and the bottom filter, 95% of the liquid enters, so clogging significantly affects the filling of the mine. Why is this happening:
- collapse of the soil, blocking the supply streams;
- Work vibration pump, provoking the rise of particles of sand or clay;
- lack of gravel backfill or insufficient layer thickness.
Elimination of siltation of the bottom
You can notice the appearance of pollution by the changed type of liquid, the bucket does not scoop up clear water, but a mixture of silt and clay. What to do in this case? We'll have to clean up the source. If the site has the possibility of connecting to central water supply, then the work will require little effort. A hose is lowered to the bottom of the well shaft, supplying clean water, and the muddy suspension is pumped out fecal pump and taken away from the source.
Cleaning the bottom of the well
You can raise the low water level in the well in another way, more complicated and dangerous. On safety ropes, a person is lowered to the bottom of the well, equipped with a bucket and a scoop. A volunteer collects sludge, and an assistant takes it out and throws it aside. The old, worn-out bottom filter also needs to be replaced by pouring new gravel.
In order to qualitatively purify the incoming liquid, multilayer filters are used, which are poured according to a certain scheme:
- for clay bottom: 1 - pebbles, 2 - gravel, 3 - sand;
- for sandy quicksand: 1 - sand, 2 - gravel, 3 - pebbles.
Location of filter layers
Attention. Fluid deficiency can cause a significant increase in its consumption. The source slowly fills up, giving the impression of its shallowing.
Violation of the integrity of the well shaft turns into the departure of water. Various factors lead to depressurization of joints:
- ground pressure;
- temperature changes;
- poor-quality sealing of joints between concrete rings.
Covering cracks
Found cracks must be repaired. For repairs, a ditch is dug outside, reaching the level of depressurization. Reliable sealing of the joint is made with special materials: "Gidroplomba" - a special dry mixture for sealing cracks in wells, cement mortar, liquid glass and sand 1:1:1. After plastering the joints, a layer of clay is poured, creating a waterproof lock.
Deepening the well - to do or not to do
If the water in the well has disappeared, then beginners see the solution to the problem in deepening the mine. This choice is not always justified. Work with an old well can be compared in cost with the development of a new one, so deepening is advisable in the following cases:
- high quality well water;
- there is no possibility (place) for the device of a new source;
- complete drying up of the source.
If the well shaft is not damaged, then it can be deepened using concrete rings of a smaller diameter or a plastic pipe.
Information. Before deepening the well, it is necessary to find out the geology of the layers, otherwise you can get on the quicksand.
The working depth at the bottom is 3 m or more, it depends on several factors:
- type of soil (dense, loose);
- occurrence of the aquifer;
- volume of water inflow.
Technology of deepening the source
Before starting work, the integrity of the shaft is checked, the rings must be connected with brackets, and the joints must be well greased. If the existing well is made of rings 100 cm in size, then the diameter of the products for deepening is 80 cm. The process of additional digging is especially difficult on the quicksand, in some cases it is transferred to the winter, when the water level is minimal.
To refill the well without water, you will need to install 2-4 additional rings. Under them, you will have to remove the soil from the bottom. The work is difficult and tedious, so it is often assigned to professional teams with the appropriate experience and equipment. They will drill to the desired depth, and then install a large-section plastic pipe with slots at the bottom for water to enter.
Installation of additional rings
For self-development, you will need a pump, which will have to periodically pump out the incoming water. The excavation of the soil takes place in a container fixed on a cable with a winch. The lowering of the rings is carried out carefully, in compliance with safety standards. New shaft links are attached to it with brackets, and the seams are covered with a special solution. At the bottom, a filter is formed from a filling of various fractions.
You can evaluate the result of the work done in a few weeks. The incoming water will have to be pumped out 2-3 times until an acceptable transparency of the liquid is established.
Low water levels in wells are a common problem. There are many factors that cause moisture loss. Regular maintenance of the source, control and prompt response to a decrease in the water level will restore occupancy from minimal cost.
For areas where a well is the only source of water, a decrease in its level is more than an unpleasant event. The design itself is simple, durable, you can build it yourself, but it also has a significant drawback - it is impossible to guarantee uninterrupted water supply. The presence and amount of water in the well depends on many factors: the season, the saturation of the aquifer, the number of hydraulic structures that feed from it. Why is there not enough water in the well and what to do?
Why is there not enough water in the well?
If there is little water in a new well, then very often this is due either to errors in design, construction, or to the wrong time for digging. In the second case, the decrease in water level may be a temporary phenomenon. The height of the water column can vary seasonally within 2 m: in summer it is low, and in spring after the snow melts it is the highest.
The filling of the well depends on the depth of the aquifer, the permeability of the soil, the height of the water column. Big influence these characteristics are influenced by the climatic features of the region and the geological conditions of the area.
Even if the well is properly equipped, it is impossible to ensure its stable operation, because. water can disappear not only due to summer fluctuations in the horizon, but also due to changes in the direction of the tracks groundwater. Another common reason for a decrease in the water level in a well is earthworks in neighboring areas.
Well on the site - scheme
How to correctly "diagnose"
The first thing to do is to talk to neighbors who have dug wells in the same aquifer. If they all say that they have the same problem, then it is quite possible that the change in water level is temporary. It is worth waiting at least a month before making a final decision and acting. Delayed work on deepening can lead to a worsening of the situation.
If hydraulic structure built by the company, it makes sense to ask questions to specialist drillers. They usually know the terrain well and can give useful advice, take charge of solving the problem. Most often, drillers offer to deepen the well. This is an expensive undertaking, it is worth it only if the water has gone completely and does not return for a long time.
Scheme of well designs - perfect, imperfect, with a sump
What to do: build a new well or deepen an old one
The cost of restoring an old structure is not much lower than building a new one. It is impossible to guarantee that water will appear after deepening, so this solution is advisable if:
- there is simply nowhere to place a new building on the site;
- the materials from which the structure is made can last for several more years;
- water quality is satisfactory;
- there are no serious deformations of the column.
When deepening an old well, there is always a risk of removing too much soil. Then the entire structure of concrete rings can sag and finally block the access of water. Another trouble encountered when deepening is quicksand. It can become a problem not only for the water source, but for all buildings on the site.
It is best to consult a professional driller working in the area. If, after inspecting the old well, he advises to dig a new one, it makes sense to listen to the recommendations so as not to spend money on a deliberately unprofitable event.
How to restore the water level
If the owner of the well long time neglected preventive measures, the problem may arise due to the banal contamination of the bottom filter. In this case, it is enough just to clean it. If the well was properly maintained and the filter is in order, then you will have to deepen the shaft.
Cleaning the well and bottom filter
Perhaps water does not enter the well due to a layer of silt, sand, clay on the bottom filter. Sometimes it is enough to clean the filter, and the water flow is restored. Most affordable way- with the help of two pumps: drainage and water-lifting. The advantage of this method lies in the minimal preparatory work and no need to pre-pump water.
The water pump is lowered to the bottom with a half-meter hose, it pumps water, ensures its intensive movement, due to which the dirt rises from the bottom. As a result, a suspension is formed with sand, debris, silt. Dirty water is pumped out with a drainage pump fixed 30 cm from the bottom.
Outlet hose from drainage pump should be lowered into a volumetric tank or into a pit where it is planned to drain the dirt. The pumps work in turn: first, water, and when the water becomes cloudy, they turn it off, wait 5 minutes and turn on the drainage. To determine how clean the water is, you need to monitor the flow. As soon as the amount of sand is minimal, cleaning can be considered complete. It remains only to fill the bottom with gravel with a layer of 20-30 cm.
Note! When choosing a drainage pump, it is important not to make a mistake with the power of the model. If the productivity of the device is too low, it will not be able to pump the required amount of dirty water, and all efforts will not lead to the desired result.
Cleaning the bottom filter with a drain pump
How to deepen the mine yourself
The structure is deepened with concrete rings of a smaller diameter than those from which the main structure is made, or with plastic pipes. Rings with a diameter of 80 cm and a height of 90-100 cm are well suited. The depth of digging is determined geological features terrain and usually does not exceed 3 m. On dense soils, you can deepen the well with an open shaft without a plastic pipe. The depth in a particular area is determined by the level of the formation, the density of the soil, its ability to hold walls, and the influx of water.
Before starting work, water should be pumped out of the well. To do this, use a pump, and if the level is low, then you can get by with ordinary buckets. Then they raise sand, silt, soil. Particular care should be taken to remove the soil from under the lower ring in order to prevent subsidence of the structure. Concrete rings are pre-fastened with special brackets. If the well is located on a quicksand, you need to make sure that the lower ring does not drift to the side, otherwise further work will be greatly complicated.
Important! After pumping out the water, you need to make sure that the atmosphere at the bottom of the well is breathable. It may be contaminated with gases. To check the condition of the air, a lit candle is carefully lowered to the bottom. If it does not go out, then there is enough oxygen.
When excavating, it is necessary to ensure that the entire structure descends evenly, without distortions, to the depth of the excavated soil. Stones and cobblestones are taken out entirely, and if it doesn’t work out, they are crushed with a jackhammer. Sometimes they resort to heating and cooling boulders. Repeated temperature drops destroy the structure of the stone, and it is easier to crush it. The shaft is built up with additional reinforced concrete rings. If the rings do not move down, heavy equipment will have to be used.
Care must be taken when excavating
All work at the bottom of the well is carried out with assistants. Be sure to need insurance and strict adherence to safety regulations, otherwise there is a high probability of an accident. If you do not have the necessary knowledge and skills, it is worth hiring specialists. Works on deepening and complete cleaning of the well shaft require the ability to operate correctly in a limited space with slippery surfaces.
Wells are among the oldest sources of water supply, but interest in them does not disappear at the present time. A well-functioning well is guaranteed to provide your home quality water in the required quantities.
Quite often, well owners are faced with a situation where their wells become shallow or dry up completely. In this article, you will learn the main reasons leading to this, and possible options their elimination.
Causes leading to a decrease in the water level in the well
The water level in the well is influenced by many external and internal factors.
If a professional team was involved in the construction of a well on your site, then most of these reasons are taken into account during its construction. However, it is almost impossible to take into account all the reasons.
Sooner or later, many users have to face the problems of lowering the water level or completely drying up wells.
The main reasons may be:
- changes in geological conditions in the area where the well is located (raising the bottom elevation, which changes the debit water inflow);
- seasonal movements of the aquifer level (decreasing in summer), significantly reducing the inflow of water;
- structural defects of the well itself.
Since all these problems have been studied for a long time, there are proven and proven technologies for dealing with them, which include the repair of a well or its reconstruction. Only professional teams whose employees have necessary equipment and qualifications.
With a decrease in the water level or its complete disappearance, one should not immediately make a decision to deepen the well. Perhaps this event is temporary due to seasonal fluctuations. external factors(drought in summer or severe frost in winter). Moreover, the spontaneous performance of such work can lead to the complete disappearance of water from your well.
Earthworks as a reason for a possible change in the water level in the well
Earthworks carried out in the immediate vicinity of the location of the well can lead to a noticeable decrease in the water level in it. This may be due to drilling wells, arranging pits, pools, other wells (but with a larger displacement). In such cases, work on deepening the well should begin no earlier than 30 days later. It is possible that the water will return within the specified period.
Do not forget about the sources of water in neighboring areas. If they also have a decrease, then the reason is related to climatic features. It should be dug up only in those cases when the water is completely gone and does not return for a long time.
Do not forget that these works are quite lengthy, time-consuming and expensive.
Reducing the water level in an old well
It makes sense to deepen old wells only in cases where:
- the quality of water and its condition do not cause any complaints;
- there is simply no place for arranging a new well on your site;
- the depth of the well is already more than 10 rings;
- there are no significant horizontal displacements between them and column curvature;
- the source has dried up completely or the water in it per day is collected in volume by no more than one ring.
If none of the above signs are suitable, it is easier to dig a new well.
If you choose the soil "with a margin", then the rings of the column can completely or partially block the existing aquifer. This will require the digging of a new well, as water will simply stop flowing into the old one.
There is a high probability of getting into quicksand when deepening the well, this will damage not only the well, but also the nearby buildings, so you should definitely inspect the well with specialists.
Deepening the well as a solution to the problem
If the column is not damaged, and the source itself is in an acceptable condition, then a decision can be made to deepen it. These works are carried out according to two options: well rings of a smaller diameter or using plastic pipes. The well shaft should be deepened with the obligatory consideration of the geology of the formations.
In making such a decision, the user must understand that this procedure is irreversible. If the water does not return after such work, you will definitely have to dig a new well.
The deepening of the well is carried out at a time to a maximum depth of 3 meters or more. In dense soils, the deepening of the trunk is carried out openly, without the use of plastic casing pipes, which are installed upon completion of work.
The sampling depth depends on:
- the ability of the soil to maintain the shape of the walls without the use of casing pipes;
- soil density;
- the level of occurrence of the actual aquifers;
- the magnitude of the water inflow.
Well deepening technology
The standard diameter of well rings is 1000 mm, therefore, well rings of a smaller diameter, 800 mm, are used to deepen them. In cases where the main well is assembled from 800 mm rings, the recess is 600 mm.
It is possible to dig a well up to a depth of 15,000 mm. Further work is prohibited due to security measures. because significantly increases the likelihood of collapse of the walls.
If the soils in the area where the well is located are sandy, then it is recommended to use reinforced concrete rings of the KS-10-9 type.
All work must be carried out with strict observance security measures.
Before starting work, make sure that:
- concrete rings are fastened with special metal brackets;
- there are no traces of the rings falling out from below and their shifts;
- seams do not have large gaps.
If a well is deepened on quicksand, then the specialist performing the work should be at this time on suspended structure(swing). The work is carried out by a team of at least three people, because the selected soil should be quickly removed from the well. There are situations when it is possible to dig a well only in winter, because. water at this time is at a minimum level.
The water has completely disappeared.
Possible reasons - the aquifer on which the well worked began to give water to an additional source (another well with a greater depth or a newly drilled well). In this case, you will have to dig until the next aquifer, which, most often, is located at depths exceeding 5 meters.
The water level has dropped significantly
It's better than none at all. In such cases, it is determined with the history of the flow rate of the specified well, certain calculations are performed to determine how many meters it will be necessary to deepen the well shaft. Practice shows that the minimum levels are observed in summer (during drought) and winter.
Reasons why it is forbidden to deepen the well on your own
These reasons are:
- These works are very costly and time-consuming, therefore, they are performed for the well only once and immediately to the maximum possible depth.
- Wells are a very complex hydraulic structure. There is a whole range of technologies to prevent the destruction of this structure. For example, performing additional reinforcement of the well column, or dismantling the installed water-lifting equipment.
- Special teams have vocational training, allowing them to objectively assess the potential of the soil at the location of the well, taking into account the peculiarities of the layered arrangement of soils. For dense soils, they deepen the trunk open way, on quicksand - using special equipment.
Performing detailed calculations on the depth of the aquifer, soils, daily water inflows, etc. should be carried out by professionals. Only in this case you will receive an object, the quality of which will not cause you any complaints.
Compliance with the rules for the maintenance and operation of the well, prompt response to changes in the water level in it will allow you to perform work in a timely manner and at minimal cost, which will fully restore the efficiency of the well available on your site.
The well is often the only source drinking water in gardening partnerships or small settlements. And often their inhabitants are faced with the fact that water has left the well.
Sometimes for a while, sometimes forever. Why is this happening and what to do in such a situation?
Causes of dry wells
A dry source is not just a nuisance. If there is no other nearby, this is a real disaster. Because, as a rule, not one, but all or most of the wells in the district dry up. With what it can be connected?
Most often - with a decrease in level ground water, which can be caused by:
- Carrying out land reclamation works;
- Artificial alteration of the landscape;
- Changing the course of an underground stream;
- Depletion of an aquifer due to dry weather.
The last circumstance is the most common cause why the water left the well. Moreover, drying out or a significant decrease can be temporary, seasonal.
During the year, periods of maximum and minimum water levels can be distinguished:
- The maxima correspond to seasonal floods and are observed twice - in mid-spring and mid-autumn, when there is active snowmelt or frequent and heavy rains. As a result, the groundwater level rises, and the wells are well filled and quickly restored after pumping.
- The minima occur in the absence of recharge of aquifers from outside and correspond to the end of summer and the end of winter. In the first case, this is due to hot weather and lack of rain, in the second - due to freezing of the soil and the formation of a water-resistant layer on the surface of the earth that does not allow surface water to pass through.
Seasonal drying up or a decrease in the level are temporary phenomena. With the advent of the rainy season, the filling of the well (see) is restored, but this is not a consolation for those who need water here and now, so you have to think about how to fix the situation.
For reference. After a long summer drought in 2010, the groundwater level dropped sharply over vast areas. The result was widespread drying up, the water returned only after a year, and some remained dry.
Other reasons include siltation of the bottom of the well or improper placement of water-lifting equipment (exhaust pump). In the first case, cleaning and flushing can help, in the second, reinstalling the pump. The instruction recommends placing it or check valve lifting station at a distance of 30-50 cm from the bottom.
Where do water problems occur?
The video in this article shows that, as a rule, water is usually scarce in certain places:
- In hilly and mountainous areas.
- Side of steeper bank near rivers.
- A well next to springs, ponds, artesian springs.
- Areas of quarries and large water intakes.
- Places of accumulations of acacias and beeches.
- Poor quality water is found in drained swamps and wetlands.
- The side of the lower bank of the river where there is a high concentration of manganese and iron in the water, even at a remote location that is even a few hundred meters from the shore.
What to do
Even during construction, it must be taken into account that its filling depends on the rate of water inflow and the volume of the well itself. In turn, the filling rate is directly related to the thickness of the aquifer.
Not without reason, in the old days, before digging wells, reconnaissance of the most favorable places was carried out.
It is produced in our time, but more modern methods and with more accurate results.
There are several options for solving the problem, but first you need to make sure that it makes sense to use them, since in most cases it is much easier to dig a new well than to try to revive the old one.
revision
The first step is to determine why it leaves or why you no longer have enough of its volume. If the cause is contamination, incorrect operation or incorrect position of the pump, it will be easy to eliminate it.
If the neighbors have a similar situation, it means that as a result of drought or other circumstances described above, the aquifer has gone deep, and the well will have to be deepened.
Unfortunately, this work requires huge labor and expenses. The cost of a new well is often much lower than restoring a dry one, so it makes more economic sense to dig a new source of water.
But this is not always possible or may not be desirable for the following reasons:
- Great depth of the aquifer;
- There is no space on the site for new construction;
- The well is in excellent condition, and the water in it good quality(there is no guarantee that it will be the same elsewhere).
Then the structure should be reviewed. If a well log house (its underground part) has rotted or squinted, or if the rings have shifted relative to each other by more than 4-5 cm, there is no other way out - you need to look for a place for another source or drill a well.
Note! When deepening, there is a risk of subsidence of the underground part of the structure with overlapping of the aquifer and the risk of hitting the quicksand, which can damage nearby buildings.
Preparatory work
Before starting the main work, it is necessary to prepare:
- Dismantle the above-ground part of the well;
- Pump out water, if any;
- Carefully disconnect and lift the water-lifting equipment;
- Strengthen the walls of the well by installing staples at all seams to prevent deformation and rupture of the column.
After that, it will be time to decide on the method of deepening and whether you will do this difficult work with your own hands or use the services of specialists. The second option is more expensive, but preferable, since experience in this matter is very important, and the presence of special equipment gives more guarantees for success.
Filter cavity
This is the least time-consuming method, which, in principle, consists in drilling a well at the bottom of the well. You will need a pipe with a diameter of 500 mm with a filter at the end. It can be made independently by drilling holes at one end of the pipe and tightening it with a fine-mesh stainless steel mesh.
The finished pipe is installed on the bottom of the well and with the help of a bailer they begin to select soil from it, gradually lowering the filter deeper and deeper until it reaches the aquifer. Then the bottom is filled concrete mortar, and pumping equipment is installed on the resulting site.
As a result, you will achieve two goals at once:
- Restore drinking source;
- Get a caisson- an underground chamber in which the air temperature will not fall below zero degrees, even in winter. Of course, subject to the construction of the cover.
The pump in the caisson will not get wet from precipitation and freeze in winter, providing you with water all year round.
Advice. The caisson can be used as a cellar or storage space garden tools, equipment, gas cylinder, etc.
Deepening by digging
The mine is deepening different ways and techniques, using plastic pipes, smaller rings, digging. Deepening takes into account many factors - these are the properties of the soil, and the depth of groundwater, and the ability to hold the walls of the mine without the risk of subsidence.
So:
- The digging deepening technique includes a set of measures similar to the process of digging a well.
- This case involves the complete pumping of water, the descent of a specialist to the bottom of the well, who takes out the soil so that the own weight of the column sets the concrete rings down.
- New rings are installed on top.
- It should be noted the laboriousness of the method, the high risk of work, because the rings could lose their strength, and the shrinkage process can completely destroy them.
- In addition, the work will have to be done at a very high pace so that the settling rings do not warp or pinch.
- Otherwise, the column will not be able to lower and a significant additional amount of work will have to be spent on leveling the verticality of the structure.
- An unpleasant thing happened, and the barrel leaned to the side or went with a screw, the recess is made by smaller rings.
- Another outcome of the case, when at the base of the well lies sandy soil or a quicksand, but the trunk has retained its verticality, then a plastic pipe is used again, again with a smaller diameter of 0.9 m.
- When the shaft is bent, the bottom is lowered plastic pipe with 0.7 m in diameter.
- As you can see, various well restoration techniques are not only used individually, but also in combination.
To make sure that the thickness of the reached reservoir is sufficient, the water from the well is pumped out completely or to a certain level and the time it takes for it to reach the norm is noted.
Conclusion
It is best to deepen the well in winter or late autumn, when the groundwater is at its lowest level and in a calm state. This will allow you not to return to such expensive and time-consuming work to restore it. More detailed information you can get by watching the video in this article on the subject.
