JP3483847B2 - Intake structure of river surface water with sloped intake screen installed at floor stop - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a river surface water intake structure, and more particularly to a river surface water intake structure constructed by installing an inclined intake screen on a floor stop.

[0002]

2. Description of the Related Art Conventionally, in the intake of surface water from rivers, there is a history of damming the river water level to slow down the flow velocity and to sediment the sediment to take in the water. However, today, river-related laws and regulations require that rivers be rehabilitated to take water from a shallow depth by a moat river, with the foundation of the ground inside the bank as the intake structure that does not raise the dam considering the flood control surface. In addition, since water from this shallow depth causes problems such as inflow of soil and sediment and clogging of the intake part, these problems are solved without manual management, and a method for reliable intake is established. There must be. In addition, regarding surface water from rivers, how to reliably take in surface water that has been reduced during periods such as a dry season without environmental damage is required.

On the other hand, a method of introducing water by constructing an intake basin or an intake duct with concrete or the like at the planned river bed height is generally considered, but it is generally Kamamaba water intake, and the screen is apt to be infiltrated with soil and sediment. It has a flat bar arrangement and requires sediment management, so it is not currently used. Therefore, as an alternative to this Kamaba water intake system, a deep water intake duct was constructed in the transverse direction of the river upstream of the floor stop to prevent the inflow of sediment and rubbish, and a water sampling hole was formed on the upstream wall of the duct. Attempts were made to arrange surface areas and to arrange the stone packing such as futon baskets to the upstream side for water permeation and to take in surface water.

There are also examples in which the above-mentioned method is further pushed to deepen the intake duct and stack futon baskets on the upper part of the intake duct, but both of them are clogged due to long-term use or inflow of earth and sand or rubbish. The current situation is that it is impossible to prevent this and a large amount of regeneration cost is required.

As a development form of these floor stop-related water intake systems, a certain local government constructs a large intake frame on a shallow riverbed upstream of the floor stop and creates a grating on the riverbed surface within the frame. Laying a screen consisting of (lattice arrangement), combining a gravel sluice that cuts out part of the floor stop as a measure against sediment, and installing a large intake gate and box culvert (box type underdrain) on the bank body As a result, it has been instructed to construct a water intake method that facilitates artificial discharge of earth and sand. However, even with this method, sediment will be deposited during heavy rainfall, and pump equipment will be worn away and culverts or wells will accumulate in the sand discharge management, so repair, cleaning, and restoration will be a major issue. It becomes a thing and is not actually operated.

[0006] Next, in the water intake method invented by one of the present inventors to apply to a river with abundant flow, an intake water tapping work consisting of a receiving waterway near 45 ° and a shallow waterway is provided upstream of the floor stop. It is constructed and a surface water intake valve and an intake strainer are provided in the flow core part formed by these, and these are prevailing nationwide as an excellent water intake system. However, this method is difficult to apply when the slope of the river is gentle or when the flow rate is small and the water flow does not work.

[0007] Furthermore, Japanese Patent Application Laid-Open No. 2 (1994) filed and published by the present inventor
The invention of the 000-213010 "inclination screen for mountain stream intake" is composed of an overflow weir plate from the upstream side, a blind part made of a flat plate, and a wedge wire row perpendicular to the flow direction, with the apex of each wedge wire section facing downward. An upper screen whose base has a predetermined depression angle toward the upstream,
It is composed of a lower screen that is composed of similar wedge wire rows and has a similar bottom edge with a predetermined elevation angle toward the upstream side, and a plurality of parallel protective plates that are arranged in the flow direction so as to cross each of these parts vertically. It is a thing.

The above inclined screen is protected from boulders by the parallel protection plate, overflows and drops the running water from the weir plate, forms a water film in the blind portion, and further repels earth and sand and the flow by the depression angle of each wire of the upper screen. By raising it and straddling this water intake structure, the water flow that has become a clear water film is actively taken in by the screen eye (slit) guidance effect formed by the elevation angle of each wire of the lower screen. This is an epoch-making water intake method that can take in clear water without clogging, but it is limited to stream water intake.

[0009]

SUMMARY OF THE INVENTION The present invention focuses on the effect of a wedge wire screen developed for mountain streams, and this screen structure has a large amount of water, but the water quality is eutrophication to generate algae and flow. A river surface water that can be applied to a general river with a large amount of poppy, and that its fine slits prevent the invasion of aquatic organisms such as fish, and that it can stably take water from the time of flood to the time of drought without destroying the river environment. It is intended to provide a water intake structure.

[0010]

In order to solve the above-mentioned problems, the present invention sets the water flow side of the revetment foundation on both banks to a vertical surface, and the upper surface of the upstream side between the opposed vertical surfaces is the planned river bed height, and the downstream side. A floor stop with an upper surface that is lower than the planned river bed height on the downstream side is applied, and between the upper surface on the upstream side and the upper surface on the downstream side of the bed stop, it is joined to the intake gutter pipe that penetrates under one of the seawalls. The intake duct is recessed, and the invasion of fish, etc. is blocked along the straight gentle slope on the intake duct from the upstream upper surface to the downstream upper surface so that the bottom surface of each wedge becomes a floating bed piece. Install a water intake screen equipped with a row of wedge wires arranged with a narrow gap, and connect the end of the water intake gutter pipe to the discharge tank via a pump and connect the water intake gutter pipe to the floor stop. On the other side of Between the foundation and intake screen mounting unit, which is constituted of the intake structure of river surface water, characterized in that a fish ladder that connects the upstream and downstream beyond the floor stop Engineering.

According to the above construction, the size (angle) of the gentle slope drop of the floor stopper, the size of the intake duct provided in the range of the gentle slope, the wire size and the arrangement of the wedge wire row of the main part of the intake screen. By selecting the design, etc., it becomes possible to prevent the invasion of aquatic organisms such as fish and the drift of sediment and the like, and it is possible to perform the optimum water intake according to the water flow conditions and the required water intake of the river. Further, according to this configuration,
The fishway provided in the floor stop allows fish and other fish to pass between the upstream and downstream sides without difficulty, so that an eco-friendly water intake action that maintains the river ecosystem is carried out.

As a second means for solving the problems, the present invention is arranged such that each wedge wire in the wedge wire row of the water intake screen is arranged so as to be orthogonal to the water flow flowing down the floor stopper, and each wedge wire row portion on the upstream side is arranged. The bottom surface of the wedge has a predetermined depression angle toward the upstream of the gentle slope, thereby forming a sliding part wedge wire row that repels the flow of sand gravel and leaves so that it does not pass through the screen, and the wedge wire row on the downstream side. Each wedge bottom surface of the portion has a predetermined elevation angle toward the upstream of the gentle inclination, thereby forming a water intake wedge wire row that actively intakes water into the water intake duct.

According to the structure of the wedge wire row,
Each wedge bottom surface (flow bed piece) on the upstream side has a predetermined depression angle toward the upstream of the gentle slope, or conversely, there is an upslope toward the sloped downstream, which results in a fine flow. Etc. are also repelled in the process of flowing on the bottom surface of one of the upstream wedges, and are flowed downstream of the river across this floor stopper. In addition, each wedge bottom surface (flow bed piece) on the downstream side has a predetermined elevation angle toward the upstream of the gentle slope, and conversely, it is a downward slope toward the sloped downstream, so that it is upstream of the wedge bottom surface. The end stands upright against the water flow, receives the water film that collides along the downward slope of the immediately preceding wedge bottom surface, and actively guides it into the intake duct through the wedge gap.

As a third means for solving the problems, the present invention provides a linear gentle inclination between a vertical end face forming a downstream end of an upstream upper surface in a floor stopper and an upstream end of a wedge wire row in a water intake screen. A blind part consisting of a gently sloping surface is arranged along with a width that extends in the water flow direction across the blind part and the wedge wire row and forms a height protruding from the surface of the blind part and the wire row. And a plurality of sub parallel elongated protective plates. As a result, the surface water that overflows / falls from the upstream end surface of the floor stopper is rectified in the blind part, and the water of a thickness suitable for undergoing the processing (sliding and water intake) peculiar to the upstream and downstream wedge wire rows described above. It becomes a film, and if there are boulders from the upstream side, they will roll and pass over these blinds and wedge wire rows without hitting them directly.

As a fourth means for solving the problems, the present invention provides a water reserving pond located immediately downstream of the floor stop to a depth deeper than the riverbed height on the downstream side of the floor stop, so that water intake and sediment at the time of drought can be prevented. It is configured so as to contribute to the prevention of the inflow of poultry screen and the formation of fish nest. That is, 10
Since it is impossible for fish and other organisms to inhabit when water is taken up to near 0%, it is legally mandatory to establish a deep water pond just downstream of the water intake section. Mizusoike, which has a floor stopper on the upstream side, is a nice fish nest. In addition, the floor stop itself, which is firmly constructed in the water flow, becomes a scouring site by the water flow on the upstream side and the downstream side (especially due to the existence of the water reserving pond actively on the downstream side), It will help maintain the Pond and will be scoured further due to the generation of kick water during rainfall.

As a fifth means for solving the problems of the present invention, an air pipe having a large number of nozzle holes connected to a compressed air source is installed in a water intake duct, and this is set at a lower limit by a timer or at a set time by a timer. When the water level is detected, the nozzle hole is used to aerate the water to contribute to removing the clogging of the water intake screen. In other words, the compressed air discharged into the intake duct expands in water, penetrates the water flow film through the screen gap, and blows out into the atmosphere, and the foreign substances such as soil and sediment that flow in the gap are also blown off and discharged downstream. , Play the screen gap.

The construction itself in which the backwash ventilation pipe is provided in the water intake structure is the "river surface water intake method with an intake strainer and an automatic backwash device", which was invented by the present inventor and registered as Japanese Patent No. 2567343. There is prior art entitled.
In the present invention, the water intake portion is composed of a wedge wire row, and since the wedge screen gap can be made smaller than that of a round bar lattice or the like in which the fine particles of dust are easily clogged, even with the same amount of compressed air, the force of air ejection from the gap is It becomes relatively large, and the reproduction of the screen gap can be performed more effectively.

As a sixth means for solving the problems of the present invention, a reflux pipe which branches a discharge pipe connected to a pump for returning to a water intake duct is installed, and a tip of the reflux pipe is provided on a downstream side wall of the floor stopper. It is formed as a nozzle that opens and generates a sweep flow along the bottom of the water pond. In the water intake structure of the present invention, the gentle inclination of the screen surface formed on the floor stopper has a certain sweeping effect,
By giving a sweep flow along the bottom of Mizusui Pond, the sediment deposited in the range of the Mizusui Pond can be appropriately swept out from the floor stopper.

Regarding the nozzle sweep flow, there is a prior art entitled "Nozzle Sweep Water Intake Device" which was also invented by the present inventor and registered as Japanese Patent No. 1853680. In the present invention, the tip of the reflux pipe opened on the downstream side wall of the floor stopper as a sweep nozzle is directed toward the bottom of the water reserving pond positively provided in contact with the downstream side wall. It enables effective sweeping, unlike when directed towards the vague goal of deposits.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, an intake structure for river surface water in an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a plan view of the embodiment in which the lower side of the figure is taken as the upstream side and the two banks, the shore and the riverbed are seen through, and FIG. 2 is taken along the line AA of FIG. The cross section of the river is shown in the figure. Revetment 1 on both banks
a and 1b are formed, and the water flow side of the revetment foundation 2 such as concrete on both banks is a vertical surface, and a floor stop 3 made of concrete or the like is also installed between the vertical surfaces of the revetment foundation 2 facing each other across the water flow, The upper surface 3a of the upstream side has a planned river bed height, and the upper surface 3b of the downstream side has a downstream river bed height lower than the planned river bed height. An intake duct 4 is recessed between the upstream side upper surface 3a and the downstream side upper surface 3b, and the right bank side of the duct 4 is connected to a water intake gutter pipe 5 penetrating under one of the seawalls 1b through a joint well 6. Are joined together.

The upper surface 3 on the upstream side on the water intake duct 4
The linear gentle slope from a to reach the downstream side upper surface 3b is
The gradient is about 1: 0.1 to 1: 0.5, and in the embodiment, the water intake screen 7 mainly including the wedge wire row is installed along this gradient. The water intake screen 7 is shown in FIG.
In the frame consisting of the upstream end plate 7a, the downstream end plate 7b, and the side plate (only the left side plate 7c is shown in the figure), the floor stopper 3 is shown as the left side surface (a) and the left side partial plane (b). Blind plate part S0 for rectifying the river water flowing in from the upper surface 3a on the upstream side and a water slide part S1 consisting of the upstream part of the wedge wire row forming the main body of the water intake screen.
And a water intake portion S2 composed of a downstream portion.

The wedge wires in the wedge wire rows S1 and S2 are arranged at right angles to the river water flow, with slits so that the bottom surfaces of the wedges become the bed pieces. The water that has passed through the rows of slits of the water intake screen 7 is referred to in FIG. 2 and is connected to the right bank of the river bank 1b through the intake duct 4 under the screen, the joint well 6 and the intake gutter pipe 5. Is pumped up by the pumping pump 9 in the pump chamber 8 installed in the above, and is guided to the discharge water tank 10 formed adjacently. On the right end of the intake duct 4 and the upper surface of the joint well 6, a metallic water intake frame lid 11 and a joint well lid 12 are attached, respectively.

As is apparent from FIG. 3, the intake screen 7
Includes a blind plate portion S0, an upstream portion (water flow sliding portion) S1 and a downstream portion (water intake portion) S2 of the wedge wire row.
There are therefore a number of protective plates 13 which intersect with and are therefore along the stream of water. These protection plates 13 have the same height as the frame structures 7a, 7b, 7c, ..., Protect the blind plate of the screen 7 and the wedge wire row from boulders, etc. The water flow gliding effect of the upstream side portion S1 of the wire row and the water intake effect of the downstream side portion S2 are enhanced.

As shown in FIG. 4, the wire arrangement of the upstream side portion S1 and the downstream side portion S2 of the wedge wire row is such that the upwardly oriented wedges 1 of the upstream side portion S1 are arranged.
The bottom surface of No. 4 is gradually inclined along the screen itself, that is, goes upstream along the surface of the blind plate 15, has a predetermined depression angle a ° (for example, 5 °), and sequentially forms slits at intervals of 0.5 mm, for example, and downstream. The bottom surface of each of the upwardly facing wedges 14 in the side portion S2 is also directed upstream and has a predetermined elevation angle b ° (for example, 5 °), and sequentially forms slits at intervals of 0.3 mm, for example. . In addition, R crosses the wedge wire and receives each lower wedge end.
A large number of supporting rods M, which are to be supported, are intersections of the supporting rods.

With such a configuration of the wedge wire row, the upstream side portion S1 repels foreign matters such as sand and gravel to prevent it from passing through the screen, and the downstream side portion S2 has the elevation angle. Since each wedge stands upright with respect to the water flow, water can be taken in more positively than the upstream side portion S1. In the case of this embodiment, the wedge intervals of the wedge wire rows S1 and S2 of the water intake screen 7 are sufficiently narrow as 0.5 mm and 0.3 mm to prevent fish and the like from entering, but this screen is arranged. The floor stop 3 itself should not be a barrier between upstream and downstream for fish during the dry season. Therefore, in the embodiment, as shown in FIGS. 1 and 2, a fishway 16 connecting upstream and downstream beyond the floor stopper 3 is formed between the revetment foundation 2 and the water intake screen 7 attachment portion on the left bank. There is.

Floor protection blocks 17 and 18 are formed on the river bed connected to the upper surface and the lower surface of the floor stopper 3, respectively. In the upstream block floor 17, the fishway 16
The two blocks 17 'corresponding to are also similarly paragraphed.
In the downstream block floor 18, two rows of floor protection blocks 18 ', 18 "in the range corresponding to the intake screen 7 are shown in FIG.
And the water reserving pond 19 shown in FIG. 5 (a central longitudinal sectional view taken along the line BB of FIG. 1) is formed.
In this case, the block 1 connected to the downstream horizontal height block 18
8'is inclined so as to connect the step between the former (block 18) and the block 18 "forming the depth. In addition, FIG. 6 is from the left bank side according to the line of view B'-B 'in FIG. It is the right sectional view seen, and it has shown that the floor protection block 18 which comprises the side edge of the Mizusui pond 19 was matched by the downstream horizontal height until the floor stop 3.

In this way, the water reserving basin 1 having a deeper depth than the upper surface (downstream horizontal height) of the downstream side of the floor stopper 3 is provided.
By providing No. 9, it is possible to sufficiently contribute to the intake of water at the time of drought, the prevention of the screen inflow of sediment flow and the formation of fish nests.

FIG. 7 is a sectional view taken along the line A "-A" in FIG. The structure of a compressed air source is shown. The air pipe 20 extends from the intake duct 4 along the conduit pipe 5 to the compressed air source. The compressed air source is the air compressor 21 in the pump chamber 8.
And the air tank 22 connected thereto, and the air tank 22 storing the compressed air is, for example, the pump chamber 8
The river water level in the lower sealed intake well 23 is the planned high water level 2
When it is detected by a water level gauge (not shown) that the planned river bed height 24b is sufficiently lower than 4a, the air pipe 20
The opening / closing valve is opened to strongly eject air from a large number of nozzle holes in the intake duct 4, and the slits of the intake screen 7 that are clogged due to the water level drop are aerated and washed (backwash).

Such backwashing can be performed at a time interval appropriately set by a timer as a preventive measure until the definite condition of lowering the water level is reached. The air compressor 21 operates so that the air tank 22 after the air is released quickly returns to the set atmospheric pressure and keeps this atmospheric pressure.

FIG. 8 is a sectional view taken along the line A′-A ′ of FIG. 1, in which a return pipe 25 in which the tip led into the intake duct 4 is connected to a plurality of through holes in the downstream side wall of the floor stopper 3. When,
The structure of the reflux water source to the reflux pipe 25 is shown. The return pipe 25 extends from the water intake duct 4 along the conduit pipe 5 and the air pipe 20 to the compressed air source. (Note that, in FIG. 7, the air pipe 20 is clearly shown in the relationship between the intake duct 4, the water guide pipe 5, the pump chamber 8 and the like, so the return pipe 25 is not shown, and in FIG. Air piping 2
Not showing 0. )

The reflux pipe 25 is provided by branching the discharge pipe from the pumping pump 9 to the discharge water tank 10 in the pump chamber 8, and a sufficient flow of water is supplied to the reflux pipe 25 by the valve switching operation. After returning, a sweep flow is generated along the bottom of the water pond from the opening of the downstream side wall formed as a sweep nozzle in the floor stopper 3 at the tip thereof. As a result, the sediment deposited on the Mizusui pond is washed away and removed, which contributes to the maintenance of the natural environment and the promotion of water intake.

[0033]

Since the present invention is constructed as described above,
It has the following effects. (1) In the intake of river surface water, a floor stop was applied in the transverse direction of the river, and a part of it was used as a gently sloping head drop, and an "inclined screen" with fine slits formed by wedge wire rows was installed. Therefore, the “inclination screen's effect of preventing scavenging of sediment and sediment and blocking of slits” that has been proved in mountain stream intake can also be enjoyed in the present invention. Specifically, no filtering equipment for snow removal or secondary treatment facilities such as sedimentation tanks and strainers are required, and maintenance of the intake can be omitted. It is generally applied to rivers with a small flow rate and poor action of running water, and can be used for pump-up water intake or a considerable amount of water intake by natural gradient. (2) Since the water intake screen can be made finer, for example, 0.5 mm upstream and 0.3 mm downstream, it is possible to physically prevent fish from straying and to open the fishway and water pond. By combining them, it is possible to construct an environment-friendly river surface water intake facility. (3) Screen water intake by a gently sloping head with a floor stopper, which occupies a small area and therefore requires less excavation of the riverbed, which improves workability and enables construction at low cost. (4) Similarly, since the intake screen is fine and prevents sediment and sediment, it is an indispensable intake gate structure in the traditional pipe intake that contains sediment and sediment in the gutter pipe and intake well. It is not necessary to use a fume pipe having a large diameter of 600 mmφ as the water conduit, and the construction cost can be reduced accordingly. (5) Similarly, in the conventional water intake method where sediment and drainage flow into the gutter pipe and the intake well, the pumping pump must be equipped with bladeless, non-clock, semi-open blades, special materials and mechanisms to support this. However, the pump efficiency is low and the durability is inferior, but in the present invention, since a simple and robust pump is required, the machine equipment cost is reduced and the maintenance cost and maintenance cost are saved. In addition, long life and power saving can be realized. (6) In the case of water intake from river surface water, it may be stopped when it is raining or turbid, or for agricultural water, but it is necessary to secure a certain amount of water intake for tap water and industrial water. In this respect, the water intake structure of the present invention exhibits an epoch-making effect that the inflow of earth and sand is avoided even during muddy water and the water intake is not blocked.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention, showing a state in which both banks, a shore, and a riverbed are viewed through the bottom side of the figure as an upstream side.

FIG. 2 is a cross-sectional view of a river that vertically cuts a floor stopper viewed along the line AA of FIG.

FIG. 3 is a diagram schematically showing a left side surface (a) and a left side partial plane surface (b) of the water intake screen installed in the floor stopper of the embodiment.

FIG. 4 is a partial side view showing an arrangement configuration of wedge wire rows of the water intake screen.

5 is a central longitudinal cross-sectional view of the river as seen from the left bank side along the line BB of FIG.

6 is a right side cross-sectional view of the river as seen from the left bank side along the line B'-B 'of FIG.

FIG. 7 is a cross-sectional view taken along the line A ″ -A ”in FIG. 1, showing the configuration of an air pipe arranged in the intake duct and a compressed air source connected to the pipe.

FIG. 8 is a cross-sectional view taken along the line A′-A ′ of FIG. 1, showing a reflux pipe and a reflux water source structure in which the tip led to the intake duct is connected to a plurality of through holes in the downstream side wall of the floor stopper. ing.

[Explanation of symbols]

1a, 1b revetment 2 seawall foundation 3 floor stoppers 4 Intake duct 5 Intake gutter pipe 6 junction wells 7 Water intake screen 8 pump rooms 9 Pumping pump 10 Discharge aquarium 11 Water intake frame lid 12 Bonded well 13 Protective plate 14 wedge wire 15 Blind board 16 fishways 17,18 Floor block 19 Mizusoike 20 air piping 21 Air compressor 22 Air tank 23 Closed intake well 24a Plan high water level 24b Plan riverbed height 25 Return piping

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-7-150598 (JP, A) JP-A-2000-213010 (JP, A) Actually open 3-62155 (JP, U) Patent 2589621 (JP, B2) ) (58) Fields investigated (Int.Cl. ⁷ , DB name) E03B 3/04 E02B 5/08

Claims (6)

(57) [Claims] 1. A floor in which the water flow side of the revetment foundation on both banks is a vertical plane, the upper surface of the upstream side is the planned river bed height, and the upper surface of the downstream side is a downstream river bed height lower than the planned river bed height between the facing vertical planes. A retaining pipe is provided, and an intake duct joined to an intake gutter pipe that penetrates under one of the seawalls is provided between the upper surface of the floor stopper and the upper surface of the downstream side. Equipped with a row of wedge wires arranged along the straight gentle slope from the side upper surface to the downstream side upper surface with a narrow gap so as to prevent the invasion of fish etc. so that each wedge bottom surface becomes a bed piece Installed an intake screen, connected the end of the intake gutter pipe to the discharge tank via a pump, and between the revetment foundation and the intake screen installation part on the opposite side of the floor gutter joint side of the intake gutter pipe. , Floor stopper A river surface water intake structure characterized by a fish path connecting upstream and downstream. 2. The wedge wires in the wedge wire row of the water intake screen are arranged so as to be orthogonal to the water flow flowing down the floor stopper, and the bottom surfaces of the wedges in the upstream wedge wire row portion face the upstream of the gentle slope. And a predetermined depression angle to repel wedges such as gravel to prevent them from passing through the screen, forming a sliding wedge wire row, where each wedge bottom surface of the downstream wedge wire row is upstream of the gentle slope. The water intake structure according to claim 1, wherein the water intake structure comprises a row of wedge wires for actively taking water into the water intake duct by having a predetermined elevation angle toward the water intake duct. 3. A blind consisting of a gently sloping surface along the straight gradual slope between a vertical end surface forming a downstream end of an upstream upper surface in a floor stopper and an upstream end of a wedge wire row in a water intake screen. A plurality of subordinate parallel protective plates having a width that forms a height protruding from the surface of the blind portion and the wire row while extending the water flow direction across the blind portion and the wedge wire row. The water intake structure according to claim 2, further comprising: 4. A water reserving pond having a depth deeper than the riverbed downstream of the floor stop is provided immediately downstream of the floor stop to take water in the event of a shortage of water, prevent screen inflow of sediment flow and fish nests. It is constituted so that it may contribute to the formation of
The water intake structure according to any one of 3 above. 5. An air pipe having a large number of nozzle holes connected to a compressed air source is installed in the water intake duct, and the air pipe is installed from the nozzle holes at a set time by a timer or when a lower limit water level is detected by a water level gauge. The water intake structure according to any one of claims 1 to 4, which is configured to be aerated in water and contribute to removing clogging of a water intake screen. 6. A reflux pipe that branches the discharge pipe connected to the pumping pump and returns to the intake duct is installed, and the tip of this reflux pipe is opened to the downstream side wall of the floor stopper to the bottom of the water pond. The intake structure according to any one of claims 1 to 5, wherein the nozzle is formed as a nozzle that generates a sweep flow along it.