Combined fishway suitable for water level changes of large and medium-sized reservoir areas

Abstract

The utility model discloses a combined fishway suitable for water level variation of large and medium-sized reservoir areas, which comprises a main fishway, a rest pool, an upstream gate and a downstream gate, the main fishway is provided with an upstream water inlet and a downstream water outlet, and the rest pool is positioned below the upstream water inlet and on one side of the main fishway. The side wall of the main fishway is provided with a first water passing opening and a second water passing opening which are communicated with the rest pool, the second water passing opening is provided with a fish blocking net, and the downstream gate is arranged between the first water passing opening and the second water passing opening so as to cut off or open the main fishway; when fishes cannot enter the reservoir area due to high water flow velocity at the water inlet, the fishes can stay in the rest pool for inhabiting; after the downstream gate is closed, the water level of the rest pool rises, the water head height difference of the upstream water inlet is reduced, and the water flow velocity is reduced, so that fishes are helped to enter the reservoir area through the upstream water inlet to complete upstream tracing, and the fishway can adapt to fluctuation of a certain amplitude of the water level of the reservoir area.

Description

Technical Field

[0001] This utility model relates to the field of fishway technology, and in particular to a combined fishway that adapts to water level changes in large and medium-sized reservoirs. Background Technology

[0002] During the flood season, reservoir water levels fluctuate significantly. In many large and medium-sized reservoirs, the upstream water level often varies considerably, sometimes by more than 3-4 meters. Some fishways are designed with only a single fish outlet. When designing the fishway, it is necessary to consider how the fish outlet can adapt to the reservoir water level. Currently, the design of fish outlets often refers to the normal water level and the flood limit water level, which makes it difficult to grasp the water level fluctuations. Since the referenced flood limit water level is generally relatively low, the reservoir water level is often too high. This results in a large head difference at the fish outlet location during actual operation of the fishway, and the water flow velocity at the fish outlet is too fast. Fish cannot overcome the high flow velocity barrier, making it difficult for fish to reach the reservoir location through the fish outlet. Therefore, fishways with only a single fish outlet will be unable to adapt to the large fluctuations in the upstream reservoir water level.

[0003] The current solution to the above problems is to arrange multiple fish outlets at different elevations near the reservoir area to adapt to different water levels in the reservoir. Each fish outlet generally needs to be equipped with a gate, which is opened and closed according to the actual water level in the reservoir. However, multiple fish outlets increase the design difficulty and construction cost. In order to ensure the normal operation of the fishway, the gates need to be frequently switched to complete the switching of different outlets, which can easily disrupt the stability of the water flow in the fishway and is not conducive to fish swimming upstream. Utility Model Content

[0004] This invention aims to solve the technical problems existing in the prior art. To this end, this invention proposes a combined fishway that adapts to water level fluctuations in large and medium-sized reservoirs. Even with significant fluctuations in reservoir water levels, it can help fish migrate upstream and adapt to large water level changes.

[0005] According to an embodiment of this utility model, a combined fishway adapted to water level fluctuations in large and medium-sized reservoir areas includes:

[0006] The main fishway has an upstream inlet and a downstream outlet, with the downstream outlet located below the upstream inlet;

[0007] A resting pool is located below the upstream inlet and on one side of the main fishway. The side wall of the main fishway is provided with a first water outlet and a second water outlet. The first water outlet is located above the second water outlet. The first water outlet connects the inner cavity of the resting pool and the main fishway. The second water outlet connects the inner cavity of the resting pool and the main fishway. The second water outlet is provided with a fish-blocking net. The second water outlet is also provided with a valve for opening or closing the second water outlet.

[0008] An upstream gate is arranged at the upstream inlet to close or open the upstream inlet;

[0009] A downstream gate is arranged in the main fishway and located between the first inlet and the second inlet. The downstream gate is used to cut off or open the main fishway. When the downstream gate cuts off the main fishway and the valve opens the second inlet, an induced water flow is formed in the resting pool from the upstream inlet to the second inlet.

[0010] The combined fishway adapted to water level changes in large and medium-sized reservoirs according to the embodiments of this utility model has at least the following beneficial effects: When the water level in the reservoir is too high, the head difference at the upstream inlet is large, and the water flow velocity at the upstream inlet is high, making it difficult for fish to enter the reservoir through the upstream inlet. At this time, fish can enter the resting pool through the first outlet, allowing them to stay in the resting pool first. Since the valve closes the second outlet, the fish will not leave the resting pool through the second outlet. The fish's short stay in the resting pool will not affect their upstream behavior. When the number of fish in the resting pool reaches a certain scale, the downstream gate can be controlled to completely or partially cut off the main fishway. At this time, the upstream position of the main fishway and the resting pool... The water level will gradually rise, thus reducing the head difference at the upstream inlet and reducing the flow velocity at the upstream inlet. Then, the valve is controlled to open the second outlet, allowing water to flow through it. This creates an induced flow from the upstream inlet to the second outlet in the resting pool. The fish in the resting pool will continue to swim upstream along this induced flow, eventually reaching the reservoir area through the upstream inlet and completing their upstream migration. Furthermore, because the second outlet is equipped with a fish-blocking net, it can intercept the fish in the resting pool, preventing them from leaving through the second outlet. Therefore, even if there are significant fluctuations in the reservoir water level, it can still help the fish complete their upstream migration. This fishway can adapt to large fluctuations in the reservoir water level.

[0011] According to some embodiments of the present invention, the combined fishway further includes multiple baffles disposed in the main fishway, the multiple baffles being arranged at intervals along the length direction of the main fishway, and the baffles having vertical slits.

[0012] According to some embodiments of the present invention, the area of ​​the second water outlet is greater than or equal to half the area of ​​the vertical slit.

[0013] According to some embodiments of the present invention, the combined fishway further includes a submersible pump, which is located in the resting pool and is used to transport water from the resting pool to the second outlet.

[0014] According to some embodiments of the present invention, the combined fishway also includes an underwater sonar or underwater video device installed in the rest pool.

[0015] According to some embodiments of the present invention, the resting pool is located downstream of the main fishway.

[0016] According to some embodiments of this utility model, the length of the rest pool is greater than or equal to 4m, and the width of the rest pool is greater than or equal to 3m.

[0017] According to some embodiments of this utility model, the valve is configured as a solenoid valve or ball valve.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0020] Figure 1 This is a schematic diagram of a combined fishway adapted to water level changes in large and medium-sized reservoirs, according to some embodiments of the present invention (with the valve in the closed state).

[0021] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0022] Figure 3 This is a schematic diagram of the combined fishway structure adapted to water level changes in large and medium-sized reservoirs according to some embodiments of the present invention (valve is in the open state).

[0023] Figure 4 This is a schematic diagram of the structure of a combined fishway adapted to water level changes in large and medium-sized reservoirs, according to some embodiments of the present invention.

[0024] Figure label:

[0025] A combined fishway system (1000) adapted to water level changes in large and medium-sized reservoir areas;

[0026] Main fishway 100, upstream inlet 110, downstream outlet 120, first water passage 130, second water passage 140, fish barrier net 141, valve 142, baffle 150, vertical seam 151;

[0027] Rest pool 200, submersible pump 210, underwater sonar 220;

[0028] Upstream gate 300;

[0029] Downstream gate 400;

[0030] Main water flow 500, induced water flow 510. Detailed Implementation

[0031] Currently, many large and medium-sized reservoirs in China have fishways that fail to achieve their designed fish passage efficiency. A major reason for this is the significant fluctuations in reservoir water levels during the flood season. During the flood season, the upstream water level of many large and medium-sized reservoirs often fluctuates considerably, sometimes exceeding 3-4 meters. Some fishways are designed with only a single fish outlet. When designing the fishway, it is necessary to consider how the fish outlet can adapt to the reservoir water level. Currently, the design of the fish outlet often refers to the normal water level and the flood limit water level, making it difficult to grasp the water level fluctuations. Since the referenced flood limit water level is generally relatively low, the reservoir water level is often too high. This results in a large head difference in the actual operation of the fishway, and the water flow velocity at the fish outlet is too fast. Fish cannot overcome the high flow velocity barrier and cannot swim upstream to the fish outlet. Therefore, fishways with only a single fish outlet will be unable to adapt to the large fluctuations in the upstream reservoir water level.

[0032] The current solution to the above problems involves arranging multiple fish outlets at different elevations near the reservoir to accommodate varying water levels. Each outlet typically requires a gate, which is opened and closed according to the actual water level. However, multiple outlets increase design complexity and construction costs. To ensure the normal operation of the fishway, the gates need to be frequently switched, which can disrupt the stability of the water flow within the fishway and frighten the fish, hindering their upstream migration. Frequent gate switching can also cause a sharp decrease in flow or constant water level fluctuations within the fishway, which the fish perceive as a danger signal, causing them to switch from upstream to downstream migration, or even terminate their migration altogether. This results in longer passage times for the fish, with them expending significant energy during their multiple trips through the fishway.

[0033] To solve the above technical problems, refer to Figure 1 and Figure 4 As shown in the figure, a combined fishway 1000 adapted to water level changes in large and medium-sized reservoirs is provided in an embodiment of this utility model. It includes a main fishway 100, a resting pool 200, an upstream gate 300, and a downstream gate 400.

[0034] Reference Figure 1As shown, the main fishway 100 is generally inclined. The water flow in the main fishway 100 flows from top to bottom. Therefore, the main fishway 100 has an upstream and a downstream. The main fishway 100 has an upstream inlet 110 and a downstream outlet 120. The upstream inlet 110 is located above the downstream outlet 120. The upstream inlet 110 is used to allow water from the reservoir area to enter the main fishway 100, and the downstream outlet 120 is used to allow water from the main fishway 100 to leave the main fishway 100. The upstream inlet 110 can be understood as the fish outlet. The fish in the main fishway 100 swim from bottom to top during the upstream process and finally enter the reservoir area through the upstream inlet 110.

[0035] Reference Figure 1 As shown, the resting pool 200 is located below the upstream inlet 110 and on one side of the main fishway 100. The resting pool 200 is positioned downstream of the main fishway 100 and extends along its length. The resting pool 200 can be understood as a bypass structure, connecting to the main fishway 100. The bottom wall of the resting pool 200 is flush with the bottom wall of the main fishway 100. The side wall of the main fishway 100 is provided with a first water inlet 130 and a second water inlet 140. The first water inlet 130 is located below the second water inlet 140. Above 40, the first water outlet 130 connects the inner cavity of the resting pool 200 and the main fish passage 100, and the second water outlet 140 connects the inner cavity of the resting pool 200 and the main fish passage 100. The second water outlet 140 is equipped with a fish-blocking net 141, which is used to intercept fish in the resting pool 200 and prevent fish from leaving the resting pool 200 through the second water outlet 140. Water can flow through the fish-blocking net 141, and the fish-blocking net 141 provides a certain resistance to the water flow, thus preventing the water in the resting pool 200 from passing through the second water outlet 140. (Refer to...) Figure 4 As shown, the second water outlet 140 is also equipped with a valve 142, which is used to open or close the second water outlet 140.

[0036] Reference Figure 1 As shown, the upstream gate 300 is arranged at the upstream inlet 110 and is used to open or close the upstream inlet 110. The downstream gate 400 is arranged in the main fishway 100 and is located between the first water passage 130 and the second water passage 140. The downstream gate 400 is used to open or close the main fishway 100.

[0037] Under normal circumstances, the reservoir water level is relatively normal, the water head difference at the upstream inlet 110 is small, and the water flow velocity at the upstream inlet 110 is relatively stable. Figure 1As shown, the upstream gate 300 and the downstream gate 400 are in the open state, and the valve 142 is in the closed state. A main water flow 500 is formed in the main fishway 100. The main water flow 500 flows from the upstream inlet 110 to the downstream outlet 120. Fish can go upstream along the main water flow 500 to the reservoir area. At this time, the resting pool 200 is not needed, and the valve 142 can be controlled to close the second outlet 140.

[0038] When the water level in the reservoir is too high, the water head difference at the upstream inlet 110 is large, and the water flow velocity at the upstream inlet 110 is relatively high, making it difficult for fish to pass through the upstream inlet 110. (Refer to...) Figure 3 As shown, fish can enter the resting pool 200 through the first inlet 130, allowing them to stay there temporarily. This short stay in the resting pool 200 does not affect their upstream behavior, making it a suitable habitat. Feeding can be provided when needed to meet their nutritional needs for upstream migration and further attract them to the resting pool 200. When the number of fish in the resting pool 200 reaches a certain level, the downstream gate 400 can be controlled to completely or partially block the main fishway 100. At this time, the water level in the resting pool 200 will gradually rise, and the water level upstream of the main fishway 100 will also gradually rise, thereby reducing the head difference at the upstream inlet 110 and decreasing the water flow velocity at the upstream inlet 110. Simultaneously, the valve 142 is controlled to open the second inlet 140. Therefore, an induced water flow 510 will be formed in the resting pool 200, flowing from the upstream inlet 110 to the second outlet 140. The fish in the resting pool 200 will continue to swim upstream along the induced water flow 510. The fish can successfully pass through the upstream inlet 110 to reach the reservoir area. Since the second outlet 140 is equipped with a fish barrier net 141, the fish barrier net 141 can intercept the fish in the resting pool 200. The fish will not leave the resting pool 200 through the second outlet 140. Since the fish barrier net 141 has a certain resistance, it will hinder the water flow in the resting pool 200, so that the water level in the resting pool 200 and the main fish passage 100 can rise, thereby reducing the head difference at the second outlet 140 and reducing the water flow velocity at the second outlet 140. In addition, the induced water flow 510 is also relatively gentle. Even if there are significant fluctuations in the reservoir water level, it can still help fish swim upstream through the upstream inlet 110. The fishway of this invention can adapt to large fluctuations in the reservoir water level.

[0039] Similarly, when the water level in the reservoir is low, the water level in the main fishway 100 is also low. The above operation can be used to gradually raise the water level in the main fishway 100 and the resting pool 200, and form an induced water flow 510. The induced water flow 510 is conducive to the fish completing the upstream migration.

[0040] In some embodiments, the opening or closing degree of the upstream gate 300 can be controlled according to the actual water level in the reservoir. When the water level in the reservoir or the water level in the main fishway 100 is too high, the opening degree of the upstream gate 300 can be appropriately reduced to decrease the flow rate at the upstream inlet 110 and lower the flow velocity in the main fishway 100, which is beneficial for fish to swim upstream. When the water level in the reservoir is low, the opening degree of the upstream gate 300 can be appropriately increased to increase the flow rate at the upstream inlet 110 and raise the water level in the main fishway 100, which is beneficial for fish to complete their upstream migration.

[0041] It should be noted that the above-mentioned gates can be either vertically movable gates or rotary switch gates.

[0042] Reference Figure 1 As shown, in some embodiments, the combined fishway also includes multiple baffles 150 disposed within the main fishway 100. The baffles 150 are spaced apart along the length of the main fishway 100, and each baffle 150 forms a vertical slit 151. The combined fishway of this embodiment can be understood as a fishway with vertical slits 151. The vertical slits 151 help improve the flow properties of the water in the main fishway 100, making the water flow more stable and facilitating fish to swim upstream. It should be noted that when the water level in the main fishway 100 is higher than the height of the vertical slits 151, the water level in the main fishway 100 is considered too high. In this case, the opening degree of the upstream gate 300 can be appropriately reduced.

[0043] In some embodiments, the area of ​​the second water outlet 140 is greater than or equal to half the area of ​​the vertical slit 151, which is beneficial for the second water outlet 140 to discharge water from the rest pool 200 and to form a relatively stable induced water flow 510.

[0044] Reference Figure 1 As shown, in some embodiments, the combined fishway also includes a submersible pump 210, which is located in the resting pool 200. The submersible pump 210 is used to transport the water in the resting pool 200 from the upstream inlet 110 to the second outlet 140, which can enhance the intensity of the induced water flow 510 and help the fish to move upstream along the induced water flow 510.

[0045] Reference Figure 1 As shown, in some embodiments, the combined fishway also includes an underwater sonar 220 or an underwater video device installed in the rest pool 200. The underwater sonar 220 and the underwater video device can be used to detect the number of fish in the rest pool 200, thereby knowing the condition of the fish in the rest pool 200. Based on this information, the downstream gate 400 can be controlled to perform opening and closing actions.

[0046] In some embodiments, the resting pool 200 can be a roughly rectangular parallelepiped structure, with a length greater than or equal to 4m and a width greater than or equal to 3m, and can accommodate a large number of fish.

[0047] In some embodiments, valve 142 is configured as a solenoid ball valve that can operate underwater. The solenoid ball valve passes through the side wall of the main fishway 100. The solenoid ball valve is relatively small in size, and the fish net 141 is disposed at the outlet of the solenoid ball valve.

[0048] In some embodiments, fish outlets can be provided on the side wall of the main fishway 100, and fish gates for opening or closing the fish outlets can be arranged at the fish outlets. The height of the fish outlet chamber and the height of the fish gates are generally designed to accommodate water level fluctuations of 3-4m. This combined fishway with fish gates can accommodate water level fluctuations of 3-4m in the reservoir area. When there are multiple fish outlets, for example, when 2 to 3 fish outlets are equipped with fish gates, it can accommodate water level fluctuations of 3-12m in the reservoir area.

[0049] It should be noted that the solution of this utility model can be applied to fishways with only one fish outlet or fishways with multiple fish outlets. Later, resting pools 200, downstream gates 400 and other structures can be added to the fishway.

[0050] The embodiments of the present invention have been described in detail above, and examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described above with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0051] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0052] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0053] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0054] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A combined fishway adapted to water level fluctuations in large and medium-sized reservoirs, characterized in that, include: The main fishway has an upstream inlet and a downstream outlet, with the downstream outlet located below the upstream inlet; A resting pool is located below the upstream inlet and on one side of the main fishway. The side wall of the main fishway is provided with a first water outlet and a second water outlet. The first water outlet is located above the second water outlet. The first water outlet connects the inner cavity of the resting pool and the main fishway. The second water outlet connects the inner cavity of the resting pool and the main fishway. The second water outlet is provided with a fish-blocking net. The second water outlet is also provided with a valve for opening or closing the second water outlet. An upstream gate is arranged at the upstream inlet to close or open the upstream inlet; A downstream gate is arranged in the main fishway and located between the first inlet and the second inlet. The downstream gate is used to cut off or open the main fishway. When the downstream gate cuts off the main fishway and the valve opens the second inlet, an induced water flow is formed in the resting pool from the upstream inlet to the second inlet.

2. The combined fishway according to claim 1, characterized in that, The combined fishway also includes multiple baffles disposed within the main fishway, with the baffles spaced apart along the length of the main fishway, and the baffles forming vertical slits.

3. The combined fishway according to claim 2, characterized in that, The area of ​​the second water outlet is greater than or equal to half the area of ​​the vertical slit.

4. The combined fishway according to claim 1, characterized in that, The combined fishway also includes a submersible pump, which is located in the resting pool and is used to transport water from the resting pool to the second outlet through the upstream inlet.

5. The combined fishway according to claim 1, characterized in that, The combined fishway also includes an underwater sonar or underwater video device installed in the rest pool.

6. The combined fishway according to claim 1, characterized in that, The rest pool is located downstream of the main fishway.

7. The combined fishway according to claim 1, characterized in that, The length of the rest pool is greater than or equal to 4m, and the width of the rest pool is greater than or equal to 3m.

8. The combined fishway according to claim 1, characterized in that, The valve is configured as a solenoid ball valve.

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