RU2619978C1 - Method for regulating river bed and floodplain processes in city territory - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method consists in creating barriers directing river water flow from the banks to the middle of the floodplain. The barriers are formed as longitudinal bulwarks of alluvial river bed and floodplain material with the length 100-150 m, the height of 1-3 m, at an angle of 30-45° relative to the direction of water flow and the protected bank. The river bed and the floodplain are pre-cleaned from silt, sediment, vegetation overgrowth, domestic and industrial waste.

EFFECT: invention allows to reduce the complexity and financial costs, while increasing the efficiency of regulating the riverbed processes due to the use of natural materials, in particular river alluvium, for creating the barriers guiding the riverbed water flow from the banks to the middle of the floodplain.

Description

The invention relates to the field of hydraulic engineering, environmental safety, environmental protection and is aimed at regulating the flow of water flow and channel processes by converting the morphology of the riverbed and floodplain within the city to protect against coastal erosion and improve the sanitary and hygienic conditions of the watercourse can be used in landscape design of urban river ecosystems.

A known method in which create in the channel speed, erosion and removal of alluvial deposits, with a continuous process of washing with the flow, is carried out from moving along the washing channel of the reservoir. The river basin is formed by a device with the function of a water-retaining structure with geometrically variable planning and altitude characteristics. The method is carried out using a device made of a horizontal panel with a ballast installed on it, connected to a pressure sheet by cable ties with the formation of a culvert between them, along which cylinders are fixed on the panels, adjustable with a filler. The magnitude of the opening of the slit is regulated by a movable panel overlapping it (patent for invention No. 2474642, IPC EV 3/02, EV 8/02, published 02/10/2013).

However, the known method of cleaning the channels from bottom sediments and improving the sanitary and hygienic conditions of the watercourse is technically complex, difficult to implement and expensive without taking into account the regulation of the direction of the water flow and the transformation of the morphology of the riverbed and floodplain in order to protect against coastal erosion.

There is also known a method in which six or more sections are created in a river bed by blocking sections with transverse temporary dams from coast to coast to clean rivers in the city and to destroy silt from the settling tanks of urban treatment facilities and enterprises and to eliminate landfills. Sludge sediments cleared from silt - large stones, gravel and sand are laid again on the river bottom cleared of sediments (patent for invention No. 2219305, IPC EV 3/02, EV 15/00, published on December 20, 2003).

However, the known method of cleaning the bottom sediments of the channels from the sludge is difficult to implement and financially expensive, moreover, it requires annual work, since each spring-summer flood entails the accumulation of silt and deresy in the river bed and floodplain, which in turn can contribute to the breakthrough of transverse temporary dams. Moreover, the method is limited to cleaning the bottom sediment from sludge without taking into account the regulation of the direction of water flow in order to reduce coastal erosion.

The closest technical solution is the method in which the flow elements are formed, made in the form of hydrodynamic profiles of flexible materials, fixed to the coastal supports by flexible load-bearing bonds and fixed in the bottom part of the stream, with loads attached to the aft part.

The disadvantage of the prototype method is that it is proposed to create a complex technical system of flow guiding elements in the form of channel devices and coastal supports with tensioning devices. During the annual spring-summer flood, such technical channel devices can be destroyed by a large pressure of water. Also, the proposed technical device is difficult, time-consuming and high financial costs.

The technical result is a simplification of the method, reducing the complexity and financial costs, and at the same time increasing the efficiency of regulation of channel processes through the use of natural materials, in particular river alluvium, to create barriers directing channel water flow from the banks to the middle of the floodplain.

The technical solution of the claimed method lies in the fact that, in contrast to the prototype method, barriers are formed along the channel in the direction of the water river flow in the form of longitudinal shafts from the alluvial material of the channel and the floodplain of the river 100-150 m long, 1-3 m high, at an angle 30-45 ° in relation to the direction of the water flow and the protected coast, and the channel and floodplain are previously cleaned of silt, sediment, vegetation, household and industrial waste.

The method is as follows. Barriers are created 1-5 km higher from the section of the river that needs to be protected from coastal erosion. The number and sizes of flow-guiding barriers depend on the size, morphological structure of the floodplain and river bed, the fullness and degree of coastal erosion resulting from the Coriolis force in such a way that the water flow is directed from the coast to the middle of the floodplain.

The length of the barrier is 100-150 m due to the fact that the barriers that are quite short relative to the length of the river allow taking into account meandering turns and other morphological features of the structure of the riverbed and floodplain, since the river is not a straightforward object. The barriers, interrupted, go one after another, while the beginning of the next begins above the end of the previous one, which allows to sharply reduce the speed of the water flow.

The height of the barrier is recommended from 1 to 3 m, depending on the height of the water flow during the flood season, so that the barrier should rise at least 1 m above the water mirror.

The barrier angle of 30-45 ° with respect to the direction of the water flow and the protected coast is optimal. In the case of angle indicators less than 30 °, a stormy spring-summer water stream will be able to destroy fairly steep barrier shafts and the water stream will go to the shores, and in case of angle indicators greater than 45 °, the water stream will occupy too wide a part of the floodplain and produce a wide channel, while over time, the water flow will occupy coastal positions and continue coastal erosion.

The method of regulating riverbed and floodplain river processes is recommended to be used for mountain rivers crossing urban areas on foothill plains.

Example 1. In the floodplain p. Terek (from 250 to 500 m wide), within the city of Vladikavkaz, on the section between the Krasnogvardeisky and Chugunny (tram) bridges, along the right bank create barriers in the form of longitudinal ramparts, from the material of alluvial islands located in the middle of the river flood plain 100-150 in length m, 1-3 m high, at an angle of 30-45 ° with respect to the direction of the water flow and the protected right bank. Barriers protect against active erosion the right, densely built-up coast, on which buildings and residential buildings are destroyed in places. Pre-clean the channel and floodplain from silt, sediment, household waste and vegetation overgrowth.

Example 2. In the floodplain p. Terek (from 150-350 m wide), within the city of Vladikavkaz, on the section between the Chugunniy (tram) and Kirov bridges, along the right bank create barriers in the form of longitudinal ramparts from the alluvial material of the channel and the river floodplain 100-150 m long, height 1-3 m, at an angle of 30-45 ° with respect to the direction of the water flow and the protected right bank. Barriers protect against active erosion the right, densely built-up coast, on which buildings and residential buildings are destroyed in places. Pre-clean the channel and floodplain from silt, sediment, household waste and vegetation overgrowth.

Example 3. In the floodplain p. Terek (from 120-350 m wide), in the city of Vladikavkaz, on the section between the Chapaevsky and Chinese bridges, along the right bank create barriers in the form of longitudinal shafts of alluvial channel material and river floodplains 100-150 m long, 1-3 height m, at an angle of 30-45 ° with respect to the direction of the water flow and the protected right bank. Barriers protect against active erosion the right bank, densely built up by industrial enterprises and other buildings, on which the landfill is formed. The riverbed and floodplain are preliminarily cleared of silt, sediment, household garbage and thickets of vegetation, and the coast is cleared of a landfill for solid waste of alcohol production with a length of about 1 km.

The invention allows to simplify the method, reduce the complexity and financial costs, while increasing the efficiency of regulation of channel processes through the use of natural materials, in particular river alluvium, to create barriers that direct the channel water flow in the right direction.

Claims (1)

A method for regulating riverbed and floodplain river processes in the city, including the creation of flow guiding elements in the riverbed, characterized in that they form barriers directing the water river flow from the banks to the middle of the floodplain, in the form of longitudinal shafts of alluvial channel material and river floodplains 100- 150 m, 1-3 m high, at an angle of 30-45 ° with respect to the direction of the water flow and the protected coast, and the river and floodplain are first cleaned of silt, sediment, vegetation thickets, household and industrial waste.