- Typical water supply scheme from a well
- Well types and pump selection
- What is a caisson for?
- Storage tank – purpose and placement options
- Water treatment system
- Internal water supply of a private house
The efficiency of the autonomous water supply of a private house depends on the type of well and the water supply scheme. Productivity, resource, choice of equipment, optimal operating modes, water quality are all interconnected. This article will focus on a typical water supply scheme for a house from a well and possible options for its construction.
Typical water supply scheme from a well
A typical water supply system from a well consists of the following elements:
- A well is a pipe system that serves several functions. The outer, casing, pipe prevents the walls from collapsing and protects against the ingress of upper water. In the aquifer, the casing has a perforation braided with a galloon metal mesh. This part is used for water intake and filtration of large suspended particles. The inner pipe made of food grade plastic is designed to transport water from the aquifer.
- The pump is responsible for delivering water to the wellhead and filling the storage tank. Depending on the type and depth of the well, the pump can be submersible or surface. The submersible pump is in the water and is secured with a cable to the head of the well. The surface pump is installed in the caisson.
- The caisson is a special structure buried in the ground so that the head of the well is below the freezing level of the soil. The pipes of the external part of the water supply and the power supply cable of the pump are also brought here. Shut-off valves, protection and automation elements, a storage tank can also be located here..
- A storage tank (or a hydraulic accumulator) is used to create “operational“ water reserve and pump optimization.
- The pumping station forms a stable head in the internal water supply.
- The water treatment system is responsible for filtering the water. Depending on the purpose, the degree of cleaning may be different for each connection point.
- The internal water supply system performs the function of delivering water to each point of consumption.
Well types and pump selection
For autonomous water supply, two types of wells are used: “On the sand” and “on lime“. In the first case, drilling is carried out to the aquifer of coarse sand, in the second – to the aquiferous porous limestone strata. Each area has its own peculiarities in the occurrence of such layers, but the general fact is that the depth of drilling on sand is much shallower and is usually in the range of 15–35 m.
1. Well for limestone. 2. Well on the sand. 3. Abyssinian well
Wells on sand are easier to drill, but they have low productivity, and with long interruptions in work (for example, seasonal residence), there is a threat of siltation of the galloon filter.
Wells for lime have a high productivity – there are layers that can provide water to an entire village. But the drilling depth can reach 200 m, which entails an increase in the cost of the work itself and the cost of equipment.
“A heart“ any autonomous water supply system is a pump. Both a well for sand and a well for lime work with submersible pumps. The pump is chosen depending on the depth of the well and the required performance of the system, and this directly affects its price.
Many different models of borehole pumps are produced and among them you have to choose the best option in terms of technical characteristics and dimensions.
There is another type of well – the Abyssinian well. The difference is that the well is not drilled, but pierced. “Working“ the lower section of the pipe has a pointed tip, which literally pierces the soil to the aquifer. As well as for a well on sand, this section of pipe has a perforation closed by a galloon mesh filter, and so that the filter is held in place during a puncture, the diameter at the tip is larger than that of the pipe. The pipe itself performs two functions simultaneously – casing and water transportation.
The Abyssinian well was originally conceived to work with a manual pump. Now for water supply of private houses from the Abyssinian well, surface pumps are used, which, taking into account the depth of the caisson, can work with wells up to 10 meters (and then provided that the diameter of the pipe does not exceed 1.5 inches). The advantages of this type of well include:
- ease of manufacture (provided that there is no exit of rocks on the site);
- the possibility of arranging the head not in the caisson, but in the basement (under the house, garage, outbuilding);
- low price of pumps.
- short service life;
- low productivity;
- unsatisfactory water quality in regions with poor ecology.
What is a caisson for?
In addition to protecting the head of the well from freezing in winter, the caisson must have reliable waterproofing of the walls and floor, as well as shelter the equipment from precipitation.
1. Luke. 2. Point of entry of the pipe going to the consumer. 3. Corrugated walls make the caisson stronger. 4. The ladder allows easy access to the caisson. 5. At the bottom of the caisson there is a prepared branch pipe for the wellhead
Caissons can be made from brick or concrete yourself (like a strip monolithic foundation). But there are enough offers for the sale of ready-made metal or plastic forms, with a hermetically sealed lid, a ladder, holes for the head of the well and the supply of utilities.
The dimensions of the caissons can be different: from a relatively small pipe in diameter (so that a person can fit when carrying out equipment maintenance), to a full “cellars“, in which there is enough space even for a storage tank.
A steel caisson is much stronger than a plastic one, but it is also heavier, it is difficult to install it in place
Storage tank – purpose and placement options
Apart from the cost of the well itself, the pump is the most expensive element of an autonomous water supply system. In fact, this is an electric motor, and for him the most “extreme“ mode is a start. Frequent stops and starts lead to a decrease in the resource.
To reduce the number of operations and not turn on the pump every time the tap is opened, a storage tank is used. It accumulates the “operational” supply of water, and the automatic equipment turns on the pump when the level drops to the minimum level and turns off when the maximum level is reached. This requires a float switch (set to two levels) or a pressure sensor that will control the starting of the pump. Moreover, the control can be built on the principle of a frequency-controlled electric drive, with a smooth start and stop of an asynchronous electric motor.
There are two options for placing the accumulator: on the same level with the head of the well and in the attic or attic of the house (if they are insulated and heated).
The layout of the storage tank at the same level with the head of the well. 1. Caisson. 2. Well. 3. Accumulating capacity. 4. External water supply, laid below the freezing level. 5. Pumping station. 6. Internal water supply
Layout of the storage tank in the attic. 1. Caisson. 2. Well. 3. Internal water supply. 4. Storage capacity. 5. Internal piping
In the first case, to supply water to consumers, another pump is needed, or rather, a pumping station, which turns on when the tap is opened and the pressure in the pipe decreases (there is a check valve and a pressure switch in the control circuit). The pressure in such a system is consistently high, but the operation of the internal water supply will depend on the power grid.
In the second case, water is supplied to the points by “gravity”, but the water from the head will need to be raised a few more meters, and this is an additional load on the submersible pump. In addition, the pressure in the system will be low and depend on the water level in the tank..
Water treatment system
Well water needs to be treated. It begins already at the stage of water intake, since solid suspended particles have a bad effect on the operation of the pump. In the future, in order to bring the water quality to the required one, a whole water treatment system is needed.
Water treatment complex. 1. Coarse filter. 2. Aerator. 3. Deironing filter. 4. Softener filter. 5. Recovery tank with salt concentrate. 6. Fine filter. 7. Ultraviolet disinfectant. 8. Compressor. 9. Bypass line valve
The first coarse filter is placed in front of the storage tank. It reduces the load on the pumping station. But after it, the water can only be used for irrigation. And for the operation of the boiler, heating system, dishwasher and for personal hygiene, the water must be of the same quality as drinking water – fine suspended particles and salts lead to deposition in the form of precipitation and scale, and this will lead to equipment failure.
A specific configuration of a purification system can only be built on the basis of laboratory analysis of water. The most common components of water treatment are:
- fine filter from mechanical impurities;
- water softener (reduces carbonate and non-carbonate hardness);
- purification of iron ions;
- chlorination or ultraviolet sterilization, another fine filter (carbon or fine-grained sand);
- decrease in acidity.
As a separate option, a reverse osmosis filter can be installed in the water treatment system to obtain the highest quality drinking water. It is after it that the water is best suited for cooking and drinks..
Internal water supply of a private house
Internal wiring of a water supply system in a private house, in principle, does not differ from the standards of a city apartment.
Plumbing diagram in a private house with a well. 1. Well. 2. Storage capacity. 3. Pumping station. 4. Water treatment. 5. DHW circuit. 6. Internal water supply with collector wiring. 7. Reverse osmosis purification unit
If the storage tank is on top, then use the top wiring without pumping water.
When placing a hydroaccumulator in a caisson or basement, use the bottom wiring with pumping water.
The main advantage of a private house is the ability to use collector, rather than sequential wiring. In this case, a separate pipe is led to each consumer, and they do not branch off from the common pipe using a tee. And then the pressure (pressure) of water at the point of consumption will not depend on the use of water by other consumers up to this point – only the distance from the pumping station and the difference in level will affect.