Country wells are silted up faster. If the water is not pumped out regularly, the strainer will not rinse naturally. At the same time, the water pressure drops, and a turbid dirty liquid begins to flow into the tap. The problem is that the pumping equipment also suffers because the casing is clogged with sand or clay. If an ordinary sand well is cleaned on average once every 5 years, then the summer cottage needs to be inspected more often.
The main causes of clogged water wells
Sources are silted up in the following cases:
- During installation, the workers forgot to isolate the bottom layer of the soil. Usually, coarse gravel is used to prevent dirt from rising during pump operation.
- Incorrect pump selection. The vibration type creates strong vibrations, which causes small particles of dirt to move and enter the house along with the liquid. The rest of it settles on the strainer or in the equipment case.
- Breakage inside the well. There have been cases that when using a plastic casing pipe, it was exposed to quicksand - moving sand from an aquifer. Below 25 meters, plastic is ineffective and often bursts, causing dirt to enter the pipe.
- Incorrect well design. While drilling, the workers violate the project conditions, so the productivity of the source turns out to be less than expected.
- Filter overgrowth with silt, clay, salt deposits or iron ions.
- Filter breakthrough due to high water velocity.
- Replacement of a sandy layer with a clay layer due to ground movements. As a result, the filling of the well deteriorates or the water disappears altogether.
- Incorrect operation of the source. Silting can occur in the interval from 2 to 3 months if it has not been pumped. Depending on the condition of the filter and the composition of the soil, this process can take up to a year.
Poor water supply is not always related to the condition of the well. Wear of pumping equipment is one of the reasons for a drop in head. In submersible units, due to sanding of the source, the rotor blades are worn out and the productivity drops by 25 - 30%.
Before inspecting the well, you need to get the pump, disassemble it and assess the condition of the internal parts of the structure. It may be enough to change or repair the device. In this case, the quality of the water will be good, but the amount of liquid entering the tap will be less.
Well breakage detection methods
Specialized firms use the video diagnostics method, which allows you to view each area on a computer monitor. After that, an estimate is made for the required amount of work. The method is unmistakable, but only the company's specialists have cameras that can work underwater.
It is possible to independently determine the breakdown only by examining each individual unit - the pump control unit, the unit itself, pipe connections, wells and its components. If water is detected in the caisson, the pump may have closed due to depressurization. In the winter season, ice accumulates on the inner walls of the pipes, the operation of the water intake system is disrupted.
Unprofessional intervention can completely stop the activity of the source, therefore, it is better to call specialists with the necessary equipment for diagnostics and repair. After the survey, it is possible to decide whether to operate this well further or to drill a new one cheaper.
Methods for cleaning water wells in the country and the choice of method
In the arsenal of specialized companies there are several ways with which you can clean the well from silt and sand, deepen it, change the filter - these are mechanical devices and a chemical method. You can independently apply:
- bailer;
- two-pump scheme for pumping liquid;
- vibration pump;
- airlift - the formation of a foamy-air mixture.
Which of these methods to choose depends on the cause of the breakdown and deterioration of the water quality, as well as the condition of the shaft of the mine. The chemical method should be used under the supervision of specialists and only after the volume of the liquid has been determined.
Mechanical cleaning method
Mechanical methods include:
- brushes and scrapers, which remove salt deposits and clean the pipe walls;
- electrohydraulic shock;
- ultrasonic exposure;
- microexplosion.
Plugs from mineral deposits can be removed mechanically, then pumped out all the liquid with residues to the surface. After the well is filled again, it will be possible to operate it. The scrapers are selected according to the diameter of the pipe and are lowered down with rotating movements. Special machines are used to clean deep wells. It should be possible to extend the pipe with additional sections as it goes down.
A low-force explosion is used if an aquifer fissure is overgrown or a layer of clay floods over it. Hydropulse cleaning is a similar method, but in this case, special equipment is used, which is lowered to the bottom. Water hammer washes away sediments and widens water-bearing fractures.
Exposure to chemicals
You can dissolve deposits using the acid method. To do this, measure the amount of water in the source and calculate the required amount of reagent. Then it is poured into the mine and after a while all the liquid is pumped out.
This method cannot be applied without special knowledge, as excess chemicals can poison all groundwater in the area. Used citric, acetic, ascorbic acids, as well as xanthan gum, sodium benzoate. In difficult cases, stronger acids are used.
The method is used with an excessive amount of lime, iron. After purification, the water is taken for analysis to exclude the presence of chemicals in the liquid.
Bailer
This is a pipe with a diameter smaller than the casing, with sharp notches at the end. With its help, it is possible to remove sand, clay, silt from the bottom of the well and to facilitate the access of liquid through the filter.
The method is primitive and slow, but safe. The pipe is lowered down and scrolled; at this time, sediment is collected in it. A valve at the end prevents dirt from spilling back into the well. At one time, it is possible to lift from 0.5 to 2 kg of sediment, depending on the diameter of the shaft.
The method is suitable for shallow sand wells. With its help, you can annually clean summer cottages for prevention, but before lowering the pipe, you must raise the submersible pump.
Double pump method
Flushing of water wells is possible by a two-pump method. To do this, a fire hose or a pipe connected to a pump is lowered into the mine. It will pump fluid into the well under pressure. A submersible pump, on the other hand, will pump it out. The essence of the method is to thoroughly shake up all the dirt and pump it out to the surface.
In order not to flood the landscaped area, you can call a sewer truck and immerse the dirty liquid in a canister. A circular method is also used: dirty water from the well enters the barrel, from which, after filtration, is pumped back into the well by an external pump. This is a more economical cleaning.
External equipment must have sufficient power to induce fluid movement underneath.
Airlift method
It consists in supplying air from the bottom to the mine. As a result, a foamy mixture is formed, the air will begin to rise to the surface and pull all the dirt - sand, silt, clay - with it. During this time, the pumping equipment must operate at full capacity to prevent debris from settling again. If the flow rate of the well is small, an external pump is additionally installed and fluid is pumped into the well.
Cleaning with vibrations
For vibration cleaning, you can use the "Kid" pump. It is lowered on a cable to the very bottom, where the muddy layer is. During operation, the device creates a strong excitement of the liquid and pumps it out together with the dirt to the surface. To prevent the device from burning out, they periodically take it out and pump clean water, then allow it to cool down and start working again.
There are special pumps for dirty water - drainage or fecal. You can use them, in addition, there is a cutting mechanism on fecal matter, and they are more durable when working with thick drains.
Blockage prevention
Wells that are operated seasonally should be cleaned at least once every 3 years. With a certain soil composition, it may take 3 months for the filter to become overgrown with salt deposits and petrified.
The filter in the wells on the sand is installed with a minimum mesh size, sometimes the filtering zone is wrapped with geotextiles. The material has proven itself well in wells with regular pumping.
To prevent organic matter from getting inside and decay processes, it is advisable to close the top of the mine first with a thick cloth, and then install the head.
The only type of wells that least of all need repair and cleaning are artesian sources, but the price of their drilling and construction is quite high.
Well cleaning prices are determined by the scope of work and the cost of consumables such as chemicals. Self-flushing of the well is free if you do the job carefully without damaging the casing.
