Providing a suburban area or real estate with the necessary amount of water is the first and most important task of every owner, since the comfort of living depends on it. Usually a well is drilled for this purpose. But how do you know at an early stage whether there will be enough water in the future?
Characteristics of the reservoir
A well is a hydraulic structure with its own characteristics. This is:
- performance;
- diameter;
- depth;
- type.
To correctly determine its functionality, it is necessary to calculate the flow rate of the well. The exact determination of this parameter will allow you to find out whether the water intake can provide not only drinking, but also household needs in full. In addition, the flow rate of the reservoir will help you choose the right pumping equipment for supplying water masses to the surface.
Also, knowing the flow rate of a hydraulic structure will help the repair team to choose the best option for its restoration in case of problems with the operation of the reservoir.
Classification features
Determination of well flow ratewill reveal the level of its performance, which can be:
- Up to 20 m³/day (low-productivity or low-rate).
- More than 20 m³/day but less than 85 (medium production).
- From 85 m³/day and more (high capacity).
Small-yielding wells are shallow wells (up to 5 m), which have reached only the upper water layer. The amount of water in them is usually small, and the quality is very doubtful, since moisture penetrates here from the surface. If there are large auto or railway routes, enterprises, settlements nearby, then the polluted water masses, passing through a small layer of soil, are little cleaned, which is why they are practically unsuitable for drinking. The flow rate of this type of well is quite limited and can range from 0.6 to 1.5 m3 per hour.
Medium-rate hydraulic structures usually reach a depth of 10 to 20 m. The waters in them are filtered with sufficient quality, which is confirmed by laboratory studies, therefore they can be consumed even in raw form. Every hour from an average debit water body it is possible to pump out from 2 m3 of moisture. Hydroworks of a high-yielding type usually reach a calcareous aquifer, so the quality of water in them is excellent, the amount is from 3 m3 hourly.
Determining the right amount of water
To find out exactly how much water is needed for the needs of a particular site, you should count the number of taps not only inside the house, but also outside it. Each crane approximately takes 0.5 m³. For example, 5 valves will supply 2.5 m³ of water masses, 7 - 3.5 m³, etc. But this is when the taps are constantly open.
After the well is drilled and settled for several days, the water level in the production pipeline should be measured. The level of the water table before pumping is called static, and after pumping - dynamic. If the water loss is equal to the intensity of selection, then the mirror will stop at a certain level. But if the volume of water intake increases (decreases) or the flow of water masses becomes smaller (larger), then the mirror can change its level.
Performance measurement
The key to the long-term operation of any hydraulic structure is its proper operation. To do this, it is necessary to control the water pressure at least 3-4 times a year. This is done simply: for a certain period of time, any measuring utensils are filled. If its filling in each subsequent control measurement takes the same amount of time, the flow rate remains the same, which means that the reservoir is used correctly.
The increase in time to fill the vessel indicates that the amount of water masses has decreased. To make it convenient to control the situation and take appropriate measures, it is necessary to record the obtained measurement data by creating, for example, a table, and to carry out the measurements themselves after the same period of time.
Calculation of the indicator
How to determine the flow rate of a well? To do this, you need to know the indicators of dynamic andstatistical levels. Measuring them is very simple: you need to attach a load to the rope and lower it into the pipe. The distance to the water mirror from the surface of the earth is the desired parameter.
Measurements should be made before the start of pumping water and after a certain period from the start of pumping. The lower the figure, the higher the productivity of the reservoir. If the well flow rate is less than the pump capacity, then the difference in performance can be very large. Thus, the statistical level is the distance to the water from the soil surface before the start of pumping, and the dynamic level is a measurement of the level of the water table, generated naturally.
Application of formula
Having learned the time for which the liquid was pumped out, and its amount, you can begin to perform the necessary calculations. To do this, an exact mathematical calculation is used. The formula with the following symbols will help determine the exact well flow rate:
- Нst, Нд – statistical and dynamic levels.
- H is the height of the water column.
- B - performance of the pumping device.
- D - debit.
Now let's look at how the formula looks like:
D=H x V: (Nd - Nst), meter
The best way to understand how to calculate the flow rate of a well is to look at a specific example.
For example:
- Data Nst – 30 m.
- Data Nd – 37 m.
- The height of the water column is 20 m.
- Productivity of the pump unit - 2 m3/hour.
Calculate: 20 x 2: (37 - 30) and get approximately 5.7 m3/h.
To check this figure, you can use a test pumping, using a larger pump. Having made the calculations according to the above formula, you can begin to find out the specific indicator. This will help you understand how performance increases as the dynamic level increases. The following formula is used for calculations:
PM=d2 - d1: n2 - n1, where
D2, n2 are the indicators of the second check, d1, n1 - the first, and UP is the specific indicator.
At the same time, the specific indicator is the main parameter that reflects all the factors affecting the productivity of the well. It depends on the thickness of the aquifer and the design of the pipeline.
Increase in performance
If the hydraulic structure began to reduce productivity over time, the well flow rate can be increased by applying one of the following methods:
- Clean filter and pipe.
- Check the pumping equipment.
Sometimes it helps to restore the performance of the reservoir and not resort to more drastic measures. If the calculation of the well flow rate was poor even initially, then the reason for this may be either a small amount of water masses in this source or the inexperience of the craftsmen caused that there was no exact hit in the aquifer. In this case, the only way out is to drill another well.
