What to do if there is not enough water in the well. The well gives little water. Deepening wells: causes and technology

Owners of private houses who have organized water supply from a well may face a well-known problem - when the water level in the source goes down. If this happens in a country house where a person lives only in the summer, the problem is unpleasant, but not critical.

But what if the water disappeared in the well from which the residential cottage is supplied? In this case, the problem takes a much more serious turn - after all, a person is left without water, which is very, very uncomfortable and unusual.

1 How do you know if there is water in the well?

The water in the well does not have a constant and clearly maintained level - its amount is constantly changing (of course, in a not too wide range). So you should only worry in certain cases:

1. The pressure of water from the tap has noticeably weakened, and even after a while it does not increase.
2. There is a serious decrease in water in the well itself.
3. The water level remains the same, but the rise has become much slower.

First of all, you need to pay attention to the level. It can be determined by focusing on the rings (for this you need to remember at what level the water was at a normal amount).

Ideally, you should remember not only the normal level of liquid, but also the speed of its collection and pumping - so at first it is advisable to pay attention to this factor.

If everything is in order in this regard, then, most likely, the reasons lie in the operation of the equipment itself: the hydraulic accumulator, valves (which can become clogged), the pipeline (which can leak, due to which the pressure in the system will decrease).

If your well runs out of water, you should ask if your neighbors have a similar problem. Nearby sources will dry up at the same time- because they almost always feed from the same aquifer.

Thus, it is possible to easily and simply reduce the amount possible causes lack of water: if your neighbors have not lost water, then the problem most likely lies in yours. If their source is also devastated, then the reason lies in the aquifer or climate features.

2 Reasons for leaving water

There are several reasons why the fluid level may go down. And depending on why the water ran out, you should choose the appropriate solution to the problem.

The list is as follows:

1. Silting of a well.
2. Digging a deeper well next door.
3. Seasonal changes in groundwater levels (especially true in autumn).
4. Depressurization of the seams of the well, damage to the intake column.

In the first case, the mud simply clogs the aquifers.. As a result, the flow of water into the well is significantly weakened, and may even dry up completely. This can happen due to very strong silting of the source - for example, as a result of a collapse.

The second option is a fairly common problem for summer cottages and cottage villages: when neighbors in the area (and not even close ones) dig a well at home, water intake for their source will often be carried out from the same aquifer as for yours.

As a result, less water may flow into your well. And the larger the neighbors' well, the more water, of course, he will take for himself. So if your source has run out of water, ask: has anyone in neighboring areas ordered drilling in the near future?

And this applies not only to wells - but also wells, and artificial reservoirs. It happens that in cottage village one of the owners wants to create on their site artificial lake– and as a result, his neighbors face a problem with water supply.

When grinding the source, you also need to pay attention to exactly when this problem arose. Moreover, a natural decrease in the water level in underground sources can occur both in summer (due to heat and dryness), and in autumn or spring - if they are not too rainy.

So when lowering the level, you need to pay attention not only to where the water can go, but also to exactly when you encountered this problem. It is possible that when the weather changes (when the heat subsides and it rains), the water will return to its previous level.

However, in any case - if such problems arise, you should think about working on. For this reason, owners of plots with wells need to remember the following seasonal features:

• in summer, in extreme heat, and in winter - in severe frosts - the water level may decrease;
• during the rainy period, the water level may rise, during the dry period, it may decrease;
• usually the lowest level is observed in late autumn-early winter, the highest - in mid-late spring.

The most serious problem of the lack of water in the source is the violation of the tightness of the seams between. They can deform under the influence of time (however, with high-quality installation, this can take more than a decade), due to frost heaving, or simply due to poor-quality, improper and / or careless installation.

In this case, the water will simply go into the gaps between the rings into the ground. This can happen both slowly (if the earth around the rings is dense enough) or very quickly (if there are voids around the well, or the soil itself is very loose).

The problem can be exacerbated in the spring, when meltwater can erode the soil, increasing the rate of water withdrawal.

A rather unpleasant problem is also the presence of quicksand. Usually it is determined even at, but sometimes it goes unnoticed. In this case, you can search for a long time where and why exactly the water has gone.

Quicksand itself, in fact, is a loose soil (it can be dusty sand or clay particles), very strongly saturated with water - up to slumping. This mass is located in the aquifer and drifts in it. If the quicksand gets into the working, this leads to clogging of the source: such a mass does not allow liquid to pass through.

In addition, one should also take into account the peculiarities of the area itself - some areas are more prone to the disappearance (or decrease) of water. This applies to:

• hills, hills, mountainous territory;
• steep river banks (and the area located near them);
• presence of natural water bodies nearby;
• the presence of nearby quarries;
• areas that used to be swamps;
• low river banks, in the case of an increased content of iron impurities in the water (and in this case, the problem may arise even for the owners of sites located a few hundred meters from the river).

To be ready for the shallowing of the source should also be those in whose area there is an accumulation of beeches or acacias.

If the question of why and where the water went is already resolved, you can begin to solve the problem. The methods are as follows:

1. Digging a new well.
2. Digging (deepening) of an old well.
3. Repair of the column (in case of depressurization of the seams).

2.1 Digging a new well

Very often this method is the most successful solution to the problem. Deepening an old source is not an easy task; in most cases, only specialists whose services are expensive (much more expensive than digging a new well) can do it.

This option is relevant in the presence of a quicksand, serious depressurization of the seams (with a significant deformation of the column or in cases where the well is more than a dozen years old) or with significant seasonal fluctuations in the water level.

2.2 Deepening an existing well

This decision is relevant in the following cases:

1. The well was installed relatively recently, is in a normal condition (or is suitable for repair) and has normal water quality.
2. The former well is quite deep (from 8-10 rings and more).
3. There is no place on the site where it would be possible to place a new development.
4. The water in the source completely disappeared, or its flow dropped to a critical level (when normal water supply cannot be restored) - due to the fact that a well was dug in the neighborhood, fed from the same vein.
5. The well has been equipped, it has been connected to it, and if a new one is dug up, large-scale work will have to be done to remake the water supply system.

Let's mention a few key nuances of deepening:

1. Wells are deepened with rings of a smaller diameter (with an existing diameter of 1 meter, it is required to use rings of 80 cm, with an existing diameter of 80 cm, rings of 60 cm are used).
2. The depth of the recess should ideally not exceed 15 meters.
3. Deepening is best done during the minimum water level (as mentioned above, this is either winter or a dry period).

Most often, it is enough to deepen the existing source by about 5 meters - to the next aquifer. This solution is relevant for almost any problem. This option is especially convenient if the water is gone due to digging another well in the neighborhood.

2.3

If the reason for the lack of water in the source is its silting, accordingly, it needs to be cleaned. Again - most often such work is performed by specialists, since doing it yourself is quite dangerous.

In addition, in the absence of the necessary equipment and experience, the situation can only be aggravated. Another factor is that the work must be carried out extremely quickly - therefore, it is carried out by teams of several people.

Cleaning can be done using drainage pump high power, which is able to pump out dirty water.

The liquid from the source is first pumped out (you just need to worry about where exactly - any large volume container is suitable for this), and then - it is fed back under pressure.

A strong pressure raises stagnant sludge from the bottom, which is then pumped out again by the same pump. The procedure is repeated several times.

2.4 Repair of the seams of the well

In the event of depressurization, water from the source will decrease into the gaps formed. Such a problem is complicated in that it is quite difficult to diagnose its presence. This requires a complete pumping out of water - in order to determine exactly that the cause of the leak is precisely the depressurization.

If the cause is determined, it is required to ensure stable and fast pumping of water. After that, the seam is cleaned - from layers of dirt, algae, concrete crumbs.

Suitable for this as scrapers different size, and just water supplied under high pressure (it is better, of course, to combine these methods). If the concrete has crumbled in some area, it should be beaten off: otherwise repair work will not bring the desired result.

The most effective material for sealing a seam is a mixture of cement, sand and liquid glass. Such a solution hardens quickly enough - for this reason, it is necessary to pre-prepare all places for embedding, and make the mixture with the expectation that it can be used in 7-10 minutes.

The procedure itself is quite simple - with a spatula, the seams are smeared as thickly as possible (in fact, as with plastering the surface).

If the seam leaks (water oozes through it) - use cement mortars irrelevant: they simply do not have time to harden. In such situations, the site is cleared, and the incorporation is carried out using special materials - such as Peneplag, Hydrostop or Hydroseals.

2.5 How to clean the well? (video)

Please tell me what is the best thing to do in this situation.
The well was made in July 2015 in the Tuchkovo area. 11 rings the entire column is the most severe clay, the last 1.5-2 rings are fine sand-clay in which water went (an aquifer and part-time false quicksand, as I understood from other branches and descriptions of Ladomir). The whole stodb descended extremely slowly and at that moment the guys could not dig further (I myself was present all the way) it was strongly washed out from under the rings, there was a very good flow of water and washed away the fine sand around the lower rings (unfortunately the pump that they dragged was no longer raised from this depth or broken-woe to the master!). On this and finished.
Since there is no place to live there yet, the well pumped as far as possible and the builders used roughly 3 buckets a day. There is a summer water supply on the plots. All summer and autumn the water was 1.8 rings, that is, 1.4 meters. The arrival was awesome, you pump out until the frog is not fully activated, there is always ~ 50 cm of water left (the sba pump as recommended by Ladomir on neighboring branches), and the water from the bottom ash murmurs and boils. The turbidity of course also rises slightly. According to calculations, it turned out 800 liters, since this pump fired everything in 12 minutes. Back, the level was restored somewhere in half a day, but for sure in a day. In general, this suits me, but taking into account the subsequent silting or raising of the bottom, I sincerely wanted to have 3-4 rings of water in reserve in the new well.
The guys said that now it’s impossible, you need to wait for the well column to be wrapped in soil and the rings to be fixed. They say then after some time it will be possible to deepen the well for several more rings. (Again the question is somewhat how much?)
As I pumped the pump in October for the last time, I drained the system for the winter, only builders scoop up buckets and use them. Here's what happened this week. Since I decided to fill the heating system with a storage buffer of 1000 liters, I turned on the well pump. He fired 160 liters and stopped. Indeed, the water level in the well has dropped. So far, every day I can take only 130 liters (there is a water meter). While I am slowly filling the system, this suits me (I am looking for an answer on what to do and specialists who will do it), but it will not work like that. I only have a 300 liter bath.
And another important signal was a little earlier. A neighbor who has an old well located 30 meters from mine down the slope of the soil ~ 1-2 meters. At the end of January, he complained that the water in the well was 20 cm. I told him that everything is fine with me, but the guys took no more than 5 buckets a day from me and I didn’t look at the water level in the well. Now, since such a situation, I think my well is deeper and I will pump out all the water from its level, the well will dry up altogether. Now the question is: will I get by with just cleaning the well, or does it still need to be deepened? (I sincerely want to deepen once and for all while the low level of groundwater and dirt in winter when digging is less)
I can’t have the entire well column move when deepening, since it has already been inserted into the well penstock and buried in a trench and brought into the house! I repeat the well was dug in July 2015; Should I wait until the soil grabs the shaft or extend it faster with repair rings while the groundwater level is low?
Extend by how much? As far as the ground allows, this is understandable, but if it allows you to go further, then how many repair rings should you put? taking into account the fact that the neighbor was also going to go deeper!
Thanks in advance for your response and advice!

Everyone who lives in private sectors and has his own well in his backyard often encounters his problems. Cases have become more frequent when water has left the well, and if this is the only source of water supply, therefore, the elimination of dysfunction must be done immediately. You can’t immediately notice how the water level in the source disappears, so most often there is no way to save the situation.

Drying of the well occurs mainly in winter or summer periods. Basically, not one well loses moisture, but all autonomous water supply sources in the district, so it happens that there are no recovery options. To understand the nature of such a phenomenon, it is necessary to find out the reasons.

As already mentioned, the well becomes shallow at the right time if the peak use of the liquid comes. Consider several factors why moisture disappears from wells:

• ameliorative work in the fields and household plots is being intensified;
• there is a change of landscape areas by human hands;
• there is a change in the course of the aquifer;
• the flow of water is disturbed due to excessive drought;
• is disturbed, characterized by silting.

Attention! In some cases, if water has left the source, this happens for a certain period, and often the source loses its moisture forever. Such a problem requires the arrangement of a new well.

Regardless of what factor influenced the fact that the moisture was gone, it is necessary to fix the problem, especially if there is an urgent need for water.

Eliminate the causes in effective ways

When there is little moisture in the source, measures are used that have already been used a lot in practice. In the event that moisture has left the structure due to the departure of groundwater, it can be returned if the source of water supply is somewhat deepened. Here, the source is analyzed, the function, its internals and the integrity of the structure are checked directly. If the destruction of the well rings is noticed, they immediately resort to the renewal procedure, often because of this, water disappears in the structure.

They resort to the procedure of updating the walls of the shaft with special staples, dismantling the destruction, pumping out old dirt and moisture, if submersible pump out of order, replace it. In the future, if the work on repairing the structure is completed, it is necessary to deepen the shaft by several meters (upon reaching the moisture level).

You can try to return water to the well by deepening, using several options.

Important! If there is not enough water in your structure again, you need to make a new one in a place where groundwater will have an optimal level, while it needs to be equipped where there are no outbuildings.

Prevention of a decrease in the level of moisture in wells

It happens that the maximum and minimum levels of moisture in autonomous sources of water supply. That's why they affect fluid levels: during early winter and dry summers. In summer, the decrease in humidity in the wells occurs due to the lack of precipitation, and in winter - in the case of the formation of an impervious horizon due to constant frosts. During such a period, it is required to deepen or replace the well.

In some cases, there is an inflow of water. Such a period, if there is a lot of liquid at the beginning of spring (when the snow melts) and mid-autumn or winter (if the rainy season begins).

To avoid regular moisture leaving the well, it is necessary, as the source becomes contaminated and silted, to clean it using the following technology:

• the head structure is being dismantled;
• before doing an analysis of the liquid in the source and its condition, you need to pump out the water with a pump;
• if necessary, the joints between the well rings are restored and updated, all holes are neatly and hermetically hidden, if they are not there, it is better to check everything for strength;
• silt and soil blockages are removed by manual work (the use of equipment is inconvenient and inappropriate);
• disinfection, cleaning and washing of the structure is carried out, plaque is removed from the walls;
• the next step is the laying of a natural filter using pebbles of various fractions. Sometimes, if it is not there, the problem comes back again;
• in the future, a protective structure is installed and the source is brought into working condition, that is

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 with 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.

When 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 wellbore is buried openly, without the use of plastic casing pipes, which are installed upon completion of the 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 under strict observance of safety 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 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, they are 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:

1. These works are very costly and time-consuming, therefore, they are performed for the well only once and immediately to the maximum possible depth.
2. 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.
3. 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 in an 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 of maintenance and operation of the well, prompt response to changes in the water level in it will allow you to minimal cost carry out work that will fully restore the efficiency of the well available on your site.

We need wells not only where there is no centralized water supply. They generously and free of charge irrigate gardens and orchards in summer cottages, supply us with natural drinking water in private households. But what if there is not enough water in the well?

The consequences of lowering the water level in our natural spring are a lot of trouble. This situation requires the immediate restoration of the filling in our natural reservoir by any known effective ways, but preferably less time-consuming and costly.

Causes of drying

To begin with, let's determine exactly why there is little water in the well. It is known that the aquifer is usually located under a 2-meter layer of clay, so we will dig out 1.5 m of clay with a drill, then another 0.5 m of soil.

We now have 1m of water to the wet bed plus the thickness of that and plus the natural rise of the water as it accumulates. This is the required 1-1.5 m, and it remains only to see the result - whether water will be added or not.

Only by finding out why there is little water in the well, we will correct the situation.

• The reason for the drying up of 80% of wells: during drilling, they did not go deep enough, they did not reach an abundant aquifer.
• Abnormal droughts with extremely rare and very weak precipitation are a natural factor in the drying up of these natural reservoirs.

Advice!
The popular deepening method is the most acceptable - it is economical and efficient.
We will also use it in case of a shortage of water, a decrease in inflow in 1 day, frequent drying up or the revival of a dry old well.

In the picture: deformation of the well shaft, and as a result - water leakage.

• There are other reasons for increasing the already existing depth of the source: its clogging, deformation of the shaft, replacement of well rings (the price of structural elements depends on strength).

Solutions

Regardless of the type of such a source (it is tubular or mine), it is necessary to deepen the lower part of the trunk, because it is here that life-giving moisture is collected. On average, this section of the well is 2 m and is reinforced with durable material.

Sump recess

In the event of depletion of the aquifer and insufficient filling of the well, we will simply dig the lower part of such a water intake below and arrange a sump.

Now this sump grenade launcher is located inside the water-resistant layer, which makes the tank fill up much more intensively and faster:

• We deepen only once and immediately to the maximum possible distance - into 3 rings.
• If, having descended to the bottom, we find a sucking quagmire there, then we will not dig for long, especially since it is very difficult due to the continuous supply of moisture.
• Constant pumping will speed up the work. At the same time, we scoop out the thick slurry.
• We dig at the fastest and most uninterrupted pace so that the rings do not warp and disturb the verticality of the mine. For the time being, we will need only physical endurance, and not experience and qualifications.
• During the night, our deep tank will be filled - and we decide whether there is enough water or whether we need to continue working.

Accounting for soil features

We use methods for deepening wells, taking into account the composition of the soils of the aquifer, as well as the state of the trunk itself.

• On the clay in the excavated recess, we put vertical rings narrower in diameter than the original upper stem rings. For example, we will use rings not meter in diameter, like the main ones, but 20 cm smaller. If the trunk is deformed, we use rings 0.7 m in diameter.
• On sandy soils it is more expedient to use a piece of plastic pipe 0.9 m in diameter, and in a curved shaft - 0.7 m.

As you can see, this instruction is quite understandable, and a reliable safety net contributes to the quick and successful completion of such extreme work. By the way, the technology for installing new rings or pipes to lower the bottom also depends on the soil conditions:

• in dense aquifers we make a recess without casing - we put reinforced concrete rings in the dug hole;
• on quicksand sandstones, we start a casing pipe and a shield.

The size of the recess is influenced by the following parameters:

• soil density;
• its composition;
• the ability to hold the vertical;
• the level of occurrence of the underground channel;
• debit of water at the bottom of the well.

A specialist will more easily assess the situation, besides, he will be able to maintain the hydrogeological conditions of our well and guarantee its timely and sufficient filling. However, we will begin this responsible work with our own hands by installing additional brackets in the seams between the rings in order to prevent the barrel from breaking when the bottom is deepened.

Independent work

If water has disappeared in the well, we will monitor similar sources at the neighbors - they probably have the same story, and drought or frost is to blame. But if this problem is only with us, let's wait a week: perhaps there was a slight oscillation of the soil.

The best time for a planned deepening is in mid-autumn, when groundwater is at the very bottom.

Need 2 assistants:

• it is necessary to simultaneously pump out water with a deep pump;
• and quickly take the soil up.
• We dismantle the house above the well, freeing access to the well.

Staged cleaning of the well

• We will strengthen the seams between some rings with simple reinforcement - 2 metal plates per 1 seam, fixing with anchor bolts. But if there is a quicksand, we will process all the seams in this way.
• Additional staples on the first two rings will help prevent the upper ring from shifting in winter.
• Clean the bottom of the silt with a shovel and a bucket.

Deepening methods

Let's start deepening the well in one of the following effective ways.

Mechanized

• in metal or plastic pipe with a diameter of 1 m, we will make 50 holes with a 20 mm drill.
• Inside the pipe we fix a fine stainless steel mesh.
• Let's put a pump in the pipe.
• With a drill we make a 1-meter hole in the bottom of the well.
• We start the prepared pipe there so that it is not flooded from above.
• We pump out dirty water, thereby clearing the way for the influx of fresh water from the aquifer.