A well is a hydraulic structure for the regular supply of water to the economy. The most common type is a shaft well. He digs when the aquifer is located at a depth of 5-25 m. The filling depends on the type of soil, the thickness and permeability of the formation, the degree of deepening into it. After rain, the water level in the well may rise. This is a common practice. The situation is associated with an increase in the amount of moisture that entered the groundwater.
What is the optimal well depth
The walls of mine-type hydrological structures are reinforced with a wooden frame or concrete rings. In the first case, moisture resistant tree species are used: oak, pine, larch. The use of concrete rings makes work easier and faster. They are fastened together with metal brackets so that the structure does not break the movement of soil layers. The structure has a square or circular cross-section with a diameter of about 1-2 m.The upper part of the well protrudes 0.8-1 m above the ground.
The depth of the mine depends on the location of the aquifers. They are divided into several types:
- Verkhovodka - the layer is shallow (1-2.5 m), quickly filled after precipitation and melting snow. Its main disadvantage is pollution. In most regions, verkhovodka is used only for household needs.
- Interstratal waters - located between waterproof layers, are suitable for any purpose, but require sanitary inspection.
- Artesian - located at a considerable depth (40-100 m), do not require cleaning.
The filling of the well depends on the rate of flow of liquid. It can pass through the bottom or additionally ooze from the walls. According to the method of moisture intake, structures are divided into three types:
- Accumulative - an aquifer of low pressure, the level is renewed for 4-10 days.
- Key - settles on the key, quickly filled. The disadvantage is the limited volume of fluid.
- River - is characterized by a significant depth of the mine and a high level of inflow. The structure is powered by an underground river.
On sandy ground, the water column rises to 3 rings, the inflow is good and stable. The clay soil prevents the rapid filling of the mine, but the liquid mirror is kept at the level of the 5th ring.
Influence of precipitation on water level
Long-term precipitation leads to a sharp rise in the level of the upper water. If the water in the well is at ground level, there is a high likelihood of loss of waterproofing. Liquid enters the mine, which has not passed filtration by layers of soil. Typical signs of flooding:
- a sharp rise in the water level;
- visual deterioration in quality, turbidity.
When constructing a well from concrete rings, the seams between them are covered with cement mortar. Over several years of operation, due to ground movements, earthquakes, sprouting tree roots, the tightness deteriorates. Verkhovodka flows through the cracks formed. In this case, you will have to wait for the liquid level to drop, then inspect and repair the mine. A routine check is done every 4-5 years. Timely prevention will prevent well flooding. If the well is full after precipitation, it is advisable not to use it until the liquid level is pumped out and restored.
At the stage of constructing a well, it is recommended to make a clay castle and a blind area in the upper part of the structure.According to the SanPiN rules, it is necessary to arrange a barrier up to 2 m deep and 1 m wide around the head. Well-crushed clay is used. It is carefully compacted. Carelessness in the work leads to the appearance of cracks through which the top water seeps. The castle is formed with a slope from the shaft of the mine. A blind area of stones or concrete is laid over the clay barrier. The head of the well is raised by 60-80 cm. A roof is installed above it to protect it from debris.
The reason for the increase in the level may be the abundant filling of the aquifer. After several days of torrential rains or melting snow, the aquifers naturally replenish. Moisture passes to the level of deep layers and raises the water level in hydraulic structures that are fed from them.
Change in water level indicators by seasons
Experienced well owners are aware of the variability of moisture levels. It depends on external factors:
- Seasonal fluctuations. This is a natural process associated with the amount of precipitation. If their volume does not exceed 15-20% of the norm, drought sets in. The groundwater is not fed. They become shallow as a result of moisture evaporation. Fluctuations in the liquid level in the mine by seasons can be 1-4 m. The highest rate is observed in spring and autumn, during the period of massive snow melting and precipitation.
- Shallowing occurs due to large volumes of fluid consumption. The well does not have time to fill.
- Leaving the underground river. It can change the channel as a result of tectonic shifts. The device on one aquifer of another hydraulic structure will also reduce the flow rate of the well.
The rise in the liquid level after precipitation is a normal process. It is important to ensure that flooding does not occur with a performer.
