Water intake facilities from underground sources

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Water intake facilities are being built to receive water from surface sources and deep layers. They are located on the banks of reservoirs, rivers, lakes. For industrial purposes, facilities are used on the shores of the seas with subsequent supply to a pressure pipeline. If there is no fresh water in coastal areas, then a system of desalination and purification of sea water is used in accordance with economic and technical justifications.

To extract water from underground flows, deep-seated structures are installed using a pumping system. When the water level fluctuates in a reservoir, coastal structures are built on artificially created foundations, piles, foundations to protect the station from ice drift and floating objects. According to the method of location, water intake structures are coastal, special and gravity (channel).

Varieties of stations

Channel stations of gravity type are built on the shore of a shallow reservoir with a small gentle slope and soft soil. Their design provides for a receiving well, a pipeline with a freecurrent, head, protected by a lattice. The resulting water through a system of pumps is fed into the pressure pipeline for further use. Heads suit completely submerged, flooded only when spilled, or surface. The pumping station works together with a water intake or is installed as an independent device.

On the steep banks of reservoirs, water intake structures of the coastal type are provided, which in the design do not contain caps and pipelines. Water intake is provided through the holes, as its level allows it to be done under any conditions. The coastal well is arranged half a meter above the highest rise in the water level, a pumping station is required. If this indicator fluctuates significantly in the river, then the well has several separate sections in accordance with the number of suction lines. The upper windows are used to collect the surface layer during the flood, which makes it possible to receive clean liquid.

A special type of water intake station is used when a large volume of liquid is needed or if the climate requires a constant fight against ice crusts. In such water intakes, an artificial bucket is arranged according to the type of channel. Its dimensions are determined depending on the speed of ascent of deep glaciated blocks. Downstream buckets are placed downstream of the mouth to receive bottom currents and fight against deep ice floes. Buckets with a top entry are designed to be installed in the mouth against the current and serve to receive surface clarified liquid. These types of water intake facilitiesallow you to dig buckets into the coastal rock to a depth of 3.5 m or take them out into the river bed, separating them with a dam.

With the help of filtration and purification facilities, a well-clarified liquid is obtained in a flood or ice drift. Before entering the pressure pipeline, the moisture is filtered through a thick layer of gravel and sand layers naturally located on the bottom or banks, only then is it taken up by shaft, tubular or horizontal devices.

If it is required to provide a temporary supply of water, build floating or mobile water intake facilities. For the location of mobile stations on the shore of a reservoir, rail tracks with an inclination are provided, along which they move depending on the level of water rise. Floating structures are arranged on anchored barges or pontoons. The disadvantages of temporary water intakes include the fact that all pipelines are made of flexible materials, and this leads to their premature damage and inconvenience of use during the ice period.

To extract moisture from gravel and sandy soils of the upper non-pressure horizontal layer, shaft wells are arranged. The material for them is concrete on a metal frame. Water enters the receivers through holes in the walls and floor. The bottom of the well is equipped with a reverse filter layer, consisting of sand up to 0.6 m thick and several layers of gravel with a total thickness of up to 0.15 m. The well protrudes 0.8 m above the ground surface. The walls are protected by a clay lock up to 0.5 m thick, which goes underground by 0, 3-1, 2 m. An adjacentconcrete blind area with a slope from the walls with a width of 1-1.5 m.

The work of water intake facilities in the northern regions is complicated by the harsh winter climate, when open water bodies freeze. The facilities are used only during the ice melting period. The northern areas are characterized by an almost complete absence of underground sources, rare waters contain a large amount of minerals and are of little use for drinking. In winter, moisture is scarce, so it is taken from the layers located under the frozen ground. To increase the water level in reservoirs, artificial dams are being built and the area of reservoirs is being expanded, thus contributing to the regulated recharge of rivers and lakes from underground non-freezing sources.

Types of sources

Water intake for use in cities and villages is carried out from the surface and underground layers. Aquifers in the ground can be pressure and non-pressure. Horizontal layers near the surface or in the thickness of rivers and lakes are called ground layers. Groundwater is characterized by increased pollution and must be cleaned before entering the pressurized water supply.

Pressure waters completely fill horizontal layers, are located below neighboring reservoirs or serve to recharge them. Artesian springs have valuable clean water; for their extraction, such types of water intake facilities are arranged that do not contain treatment devices in their design. In the well for receiving water from the pressure horizontal layer, there is a conditional line of liquid rise, coinciding with the levelthe surface of the nearest body of water. If such a line passes above the ground surface, then moisture flows out of the well, which is called the artesian.

Pressure and non-pressure water seeping to the surface of the soil form descending and ascending springs, supplying high quality water, which is used for drinking purposes without the use of expensive purification systems. Qualitative indicators of the source, such as power, depth, mineral saturation, are used to select the type of structure of the water intake station. At the same time, technical and economic considerations and the need for a certain type of liquid (for industrial, drinking, household needs) are taken into account.

Conditions for choosing a location

The construction of water intake structures is based on forecasts of the properties of the liquid from the selected source, the need to re-equip the coastal zone, re-form the channel of a river or other reservoir, and hydraulic conditions of work. When the water level changes more than 6 m and the steep slope of the coast is sufficient for normal water inflow, combined coastal structures are built.

If average productivity is planned, due to the low height of water rise, water intakes are combined with pumping complexes. Water receivers of a separate type are built with the required low productivity and a large depth of the reservoir. If the fluctuation of the water surface is less than 6 m, the depth is small, then use the channel type of water intake with a pumping station in the design of the coastalreceiver.

Hydraulic calculation

To determine the optimal parameters of the pipeline, hydraulic calculation is used. Take into account the throughput of pipes and other elements for the entire estimated period of validity. The water consumption is defined as the need for it during the maximum analysis by the connected consumers. Based on these data, the diameters of the pipes necessary for the economically advantageous passage of a given mass with the least losses are calculated.

Make an axonometric diagram indicating the direction from the input to the attached water assembly, choosing the location with the fewest number of turns. The lengths of the sections from one nodal point to another are calculated, taking into account the number of liquid analysis points. The diameter of the pipes varies in another section; within the same section of the pipe, the same size is provided. The construction of water intake structures is carried out after a full hydraulic calculation.

Treatment facilities

Determine the quality of water based on the following indicators:

• physical properties such as haze, taste, color, odor, temperature;
• chemical qualities characterizing the ability to oxidize, hardness, active reaction, mineral content;
• bacteriological properties, which indicate the degree of contamination by bacteria entering the water from nearby sewage, precipitation, animal feces.

Drinking water is under scrutinyattention. Requirements for the quality of liquids for domestic use are standardized and are contained in GOST R51232 - 1998. The document takes into account the requirements for chemical, physical and bacterial indicators. If the purity of the water received does not correspond to the given regulatory data, then water intake treatment facilities are built. The most common cleaning methods are disinfection and clarification. For clarification, filtration and settling are used in several stages, as a result of which impurities settle to the bottom. Bactericidal irradiation, normalized chlorination, ozonation are used to get rid of pathogenic microorganisms.

Getting water from underground sources

The choice of a water intake station for receiving liquid from underground layers is influenced by the depth and thickness of the layer. Structures are divided into four types:

• water intake wells;
• mine wells;
• horizontal water intakes;
• bonnets.

Groundwater intake facilities in the form of wells or tube wells are used to extract fluid from a reservoir at a depth of more than 10 m. Construction consists in drilling a well and strengthening the walls with casing pipes. Gradually, as the depth increases, the diameter of the pipes decreases. A filter is installed in the lower part of the hole, and an observation chamber is built on the surface, above the well. If the pressure of the aquifer is strong enough, water rises to the surface under pressure, otherwise moisture is pumped upwards.

Constructions by the type of minewells are used to receive water from a depth of more than 30 m. The walls of the well - concrete, brick or wooden, often use ready-made unified elements that are sequentially installed one on top of the other. In the lower part of the walls and the bottom of the well, holes are provided for the natural flow of liquid. At the bottom, a filter layer is made of sand and gravel. With an increased need for water, several shaft wells are organized, interconnected by siphons with a water collector, from where moisture is pumped into the water supply system.

Underground horizontal water intake structures are used to collect moisture at a shallow depth. They are performed at a depth of up to 8 m from standard reinforced concrete or ceramic elements with holes or slots in the side surfaces. The simplest horizontal types are made of thinned brick or rubble masonry; inspection chambers are designed for preventive maintenance every 100 m.

Capotage chambers are used to take water from the keys. They are the simplest shaft wells, arranged above the place where water appears on the surface. To obtain liquid from descending key sources, capping chambers are made to collect moisture through vertical walls by the type of horizontal water intake.

Collection of water from surface sources

With this method of water intake, measures are taken to ensure the uninterrupted supply of moisture throughout the year. To do this, the facility is located closer to the consumer on a stable, least pollutedplace of the coast, they are building above industrial plants and sewerage sites. Water intake structures from surface sources are arranged taking into account the possible turn of the river bed over time. The elements of the system are arranged so that after the formation of an ice cover in winter, at least 0.3 m remains to the top of the structure, and the bottom of the water intake does not reach the bottom of the river by 1 m.

Water intake structures are often built according to the combined principle of two or more types, this is determined by the characteristics of the reservoir and the required consumption volume. Before the start of operation, the system undergoes a technical test. Surface water intake facilities crossing by launch are washed with water at a speed of 1 m/s. Household plumbing is chlorinated for disinfection.

Device of external water supply networks

Outdoor system includes main lines and secondary branch lines. As a pipe material, environmentally friendly components are used, selected according to the conditions of GOST. Between the intake station and the pressure water supply, the liquid passes through the treatment facilities, settles in tanks and is sent to the consumer with the help of control devices. The diameter of the pipes of the main line is taken according to the hydraulic calculation, and the branch diameters are applied taking into account the fire throughput of the liquid.

Water lifting devices

Pumping complexes are placed in the water movement circuit to convert the engine energy into hydraulic energy of the transmitted fluid. With these devicesmoisture is raised to the desired height, served over long distances and forced to flow in a closed water supply system, which implies the operation of water intake facilities. The choice of pumps for complex maintenance of water intake facilities is carried out depending on the type of engine, power, head, efficiency and other indicators. The most common in application are centrifugal pumps, which have enough advantages over other types.

Reservoirs and water towers

To achieve pressure in the water supply network and to raise liquid to high-rise floors, water towers are used, which work on the physical principle of communicating vessels. The reservoir tank in the tower is calculated on the volume of water, which regulates the supply of liquid to consumers for a certain time, if the water intake facilities from underground sources fail.

The tank of the water tower stores a supply of water needed for emergency fire fighting within 10 minutes after a fire. The water tower in the design contains a tank supporting the base, made to the height of the tallest building in the village. In the northern regions, an insulating casing is arranged, and in the southern regions only a cover is made above the tank.

Water storage tanks are placed in various places of the plumbing system, they serve to store liquid reserves. The volume of tanks depends on their purpose and the need to saturate the pressure system of consumers with water. The material for the buildings is burnt brick, various typesnatural stone and reinforced concrete. The shape distinguish between round and rectangular tanks. Overlapping is performed in a monolithic or prefabricated way.

Repair of underground and underwater pipelines

The device of water intake facilities with an extended pipeline after a certain period of operation requires periodic repair and maintenance. Sometimes the throughput of the water supply system is reduced due to the deposition of blockages and layers in the pipes. Its cleaning is carried out periodically, in mild cases it is enough to flush with a reverse or direct flow of water. For more difficult cases, use scrapers or ruffs.

Retrieving a damaged pipeline to the surface is a troublesome and costly job. Therefore, a special device was designed for cleaning, moving inside the pipe. The device moves, and rotating hard brushes remove deposits on the walls. To clean the pipeline from which the liquid has been removed, sinkers are made to prevent the pipe structure from floating to the surface.

To remove complex breaks or holes in pipes, they are raised to the surface, and after replacing the damaged section, they are lowered to the bottom again. Damage that is not too complex is repaired using underwater welding.

In conclusion, it should be noted that the installation of water intake structures requires special knowledge to determine the type of structures, choose a place and arrange structural units. But since modern consumers do not see their existence without life-giving moisture, then over timethere are new constructive solutions and ideas for extracting water from the bowels of the planet.