JPH09242038A - Water level regulating device for lakes and marshes and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water level regulating device and the method thereof in which water level can be freely regulated by a simple device and economical process, and the outstanding effect is exhibited for the contermeasure of water shortage in particular. SOLUTION: This water level regulating device for lakes and marshes is constituted of pumps 5, 6 for charging or discharging sea water of the Japan Sea, a pipe for transferring the sea water to a bag-shaped body 3, and a flexible bag-shaped body 3 for storing the sea water. In the water level regulating method using such device when the water level of a lake or a marsh is regulated by the use of this water level regulating device, the volume of the bag-shaped body 3 is changed so as to regulate the water level, by the operation charging sea water sucked from the sea by the pump 6 into the bag-shaped body 3 provided on the bottom part of the lake or a marsh 1 through a pipe line 4 connecting together the bag-shaped body 3 and the sea 2, and the operation discharging sea water sucked from the bag-shaped body 3 by the pump 5 to the sea 2 through the pipe line 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lake water level adjusting device and a water level adjusting method for the purpose of keeping the water level of lakes or dams in plains or inland areas freely and particularly substantially constant.

[0002]

2. Description of the Related Art In recent years, due to abnormal weather, long-term sunshine has continued, and drastic reductions in water levels of lakes and dams in plains and inland areas have been recorded. Especially in Lake Biwa in Shiga Prefecture, the water level may drop from the normal water level by more than 1 meter, and water intake and discharge restrictions are imposed. In recent years, concentrated heavy rains and droughts have become a major concern for stable water use.

Conventionally, in order to cope with such a decrease in the water level of a lake, there is a method in which a large number of dams are formed in a river flowing into the lake and the water level of the lake is adjusted by the amount of stored water discharged. There is also a method of creating a reservoir for supplementing the lake, storing it in the reservoir when the amount of water in the lake is large, and supplementing it when the amount of water in the lake decreases. In fact, in Lake Biwa, revetment work and improvement of the inflowing river water area have been carried out, and considerable results have been achieved, but the above-mentioned abnormal weather cannot be overcome, and recently there have been many concerns that the water level may drop. There is. Among these lakes and dams, especially in Lake Biwa, the water depth is deep and the water level drops while accumulating abundant water, so it is not possible to sufficiently discharge water to the discharge channel that supplies water to the downstream side, The mouth may be exposed above the surface of the water, and may even cause difficulties in industrial and general water use, which is taken directly from the lake. The shallow water of lakes is a place where fish living in lakes spawn, but it is exposed by changes in water level, which causes destruction of the spawning grounds, which is currently affecting the fishing industry in lakes.

[0004]

Although many practical methods for preventing water level drop have not been proposed, it is fatal that it is not easy to secure a huge amount of water for adjustment in the above method. Have a problem.

In view of such background of the prior art, the present invention is
The water level can be adjusted freely with a simple device and with an economical process, and since it also uses abundant seawater, it has a higher degree of freedom and contributes to drought control, and it also contributes to drought control. It is intended to provide a water level adjusting device for lakes and marshes and a water level adjusting method therefor, which can exert an outstanding effect in order to stably and smoothly maintain direct or indirect water use in the downstream basin.

[0006]

The present invention employs the following means to achieve the above object. That is, the lake water level adjusting device of the present invention has a pump for injecting or discharging seawater, a pipe for transferring the seawater to the bag-shaped body, and a flexibility for storing the seawater. It is characterized by consisting of a bag-shaped body, also, the water level adjusting method using such a device, when adjusting the water level of the lake using such a water level adjusting device for a lake, at the bottom of the lake. An operation of injecting seawater pumped up from the sea into the bag-shaped body through a pipeline connecting the bag-shaped body and the sea into the bag-shaped body installed, and the bag through the pipeline The water level is adjusted by changing the volume of the bag-like body by an operation of sucking up seawater from the bag-like body with a pump and discharging the seawater to the sea.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has been conducted eagerly on the problems of lakes and lakes occurring in various areas, water shortages due to the drought of dams, and water distribution restrictions, especially the problem of drought in Lake Biwa. As a result of diligently studying the method of changing only the water level of lakes and dams while maintaining the same scenery and appearance, that is, without changing the living system of living things, we arrived at a method of adopting a liquid with a higher specific gravity than fresh water, Moreover, they have reached the point of utilizing unprecedented seawater.

[0008] Specifically, the present invention sprinkles seawater into fresh water of a lake and marshes into a specific bag-like body and inflates it like a balloon, so that the water level corresponding to the expansion amount of the volume is splendidly. Has been successfully and easily increased.

That is, such a bag-like body is installed at the bottom of a lake and seawater is injected or discharged through a pipe connected to the bag-like body so that the bag-like body can be easily caused without causing trouble due to buoyancy. You can change the volume of
By doing so, the volume of the lake as a whole is changed to adjust the water level of the lake.

The present invention is characterized in that seawater is used. Since Japan is a long and narrow archipelago, the distance to the coast is at most about tens of kilometers to hundreds of tens of kilometers not only in the plains but also in the inland areas, and seawater can be easily used by pipelines. If it is seawater, consideration for the environment is necessary, but it can be used inexhaustibly. The pipeline extends from the sea to a height above the land, and is connected to a flexible bag installed in a lake. Seawater is sucked up from the sea by a pump provided adjacent to the sea, crosses a high place on the land through a pipeline, and is injected into a flexible bag-shaped body. The flexible bag-like body is spread by a mooring anchor or the like at the place where the lake is installed. Since the injected seawater has a larger specific gravity than fresh water, it can be stably installed at the bottom of the installation site of the lake. Especially in Lake Biwa, it is about 2 from the northern end of Lake Biwa to the Sea of Japan.
It is only about 5 km, and the height difference between the water surface of Lake Biwa and the water surface of the Sea of Japan is about 80 m, so there is no technical problem in raising seawater of the Sea of Japan to Lake Biwa.

The shape of the flexible bag-like body can be appropriately selected depending on the shape and size of the bottom of the lake, such as a cylindrical shape, a flat water pillow shape, and a spherical shape. Further, by adopting a bellows-like structure, the positions of the seawater injecting and extracting port can be prevented from moving much even if the amount of seawater in the bag changes, and the area covering the bottom of the lake can be made almost constant.

The amount of water level adjustment is determined by the surface area of the lake and the volume of the flexible bag of the present invention. The adjustment amount can be made by increasing the volume of each bag-shaped body of the bag-shaped bodies or by increasing the number thereof. In the case of Lake Biwa, the surface area of the lake is about 700 million square meters, which is one
The volume to compensate for the drop in the water level of the tor is about 700 million cubic meters. For this purpose, the flexible bag-shaped body of the present invention may be prepared by, for example, preparing about 1000 bag-shaped bodies having a diameter of 30 meters and a length of 1 km. 1 more
For the purpose of adjusting more than the meter, the number may be further increased or the diameter may be increased.

When the flexible bag of the present invention has a small amount of seawater or no seawater, the shape is unstable and there is a problem in handleability. Therefore, in order to stabilize the shape of the flexible bag-shaped body of the present invention, a pipe-shaped bag made of a flexible bag-shaped body is provided, and air is injected under pressure into the pipe-shaped bag. The auxiliary columns for stabilizing the shape are formed. The compressed air injection pipe support is intended to prevent the flexible bag-like body of the present invention from being wrinkled or bent and not being stably used. The bag is
From the viewpoint of stability, it is preferably engaged and connected to the anchor member, and the function of the compressed air injection pipe strut described above may be used together.

Further, when the seawater is discharged from the flexible bag-like body filled with the seawater, the bag-like body is crushed when the amount of the seawater becomes small due to the flexibility of the bag-like body, and the seawater discharge path is formed. The purpose is to prevent the discharge from becoming blocked due to blockage. The compressed air injection pipe support may be attached to the outer peripheral portion of the flexible bag-like body of the present invention or may be installed inside. The material may be the same as that of the flexible bag. The material of the flexible bag-shaped body is made of rubberized cloth in which a rubber material is laminated on a base cloth made of synthetic fibers. The base fabric is a synthetic fiber such as nylon 6, nylon 66, polyester, rayon, vinylon, etc., or a high-strength fiber thereof, or heat-resistant fiber such as aromatic polyamide fiber or PPS fiber, etc. Can be composed of In addition, the base fabric is 400 to 100 made of such fibers.
It is preferably composed of filament yarns of 00 denier. As the structure of the base cloth, a woven fabric is preferable from the viewpoint of strength and durability, and although various structures of such a woven fabric are considered, a plain woven fabric is preferable for the purpose of reinforcement. The basis weight of such a woven fabric is not particularly limited, but may be about 100 to 2000 g / m ² . 1 to 5 of these base fabrics are used depending on the required strength. As the rubber for coating, NBR, chloroprene rubber,
Synthetic rubber such as PVCl-nitrile rubber, nitrile rubber, and silicone rubber is preferable from the viewpoint of durability. A sheet material is preliminarily produced for these rubberized cloths, and joining for forming a required shape is performed by vulcanization of rubbers of the same quality.
Further, the material for the compressed air injection pipe strut may be exactly the same as the flexible bag-shaped body of the present invention.

Since the pipeline uses seawater, metal such as stainless steel which does not cause rust may be used. It is important that the joint portion with the flexible bag-like body has a flexible structure in order to prevent fatigue failure of the joint portion.

The thickness of the flexible bag of the present invention is 0.
The thickness needs to be increased in accordance with the increase of the volume of 5 to 5 cm. In consideration of safety, the possibility of leakage of seawater to the outside is extremely reduced by making it considerably thicker and by vulcanizing the rubber of the same quality as the seam.

Next, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a lake water level adjusting device of the present invention. FIG. 2 shows a plan view thereof. 1 is a lake,
For example, Lake Biwa. 2 is the sea, for example, the Sea of Japan, and the Shizume Tsuruga Bay. The distance from the northern end of Lake Biwa to Tsuruga Bay is about 25 km. The water near the northern end of Lake Biwa has a deep water depth of about 60 m. 3 is a flexible bag-like body. Even if the bag-shaped body has a diameter of 30 m, since the bag-shaped body of the present invention sinks to the bottom of the lake, it does not affect the navigation of ships or the normal utilization of life of the lake at all. Reference numeral 4 is a pipeline that connects the bag-shaped body installed in the lake and the sea to a high place therebetween. Reference numeral 5 denotes a lake-side pump for extracting the seawater of the flexible bag-like body of the present invention and returning the seawater to a sea over a high place. This pump is about 1 from the surface of the lake
It will be installed at an altitude difference of 0 meters or less. Further, 6 is a pump which sucks up seawater, crosses a high place, and injects seawater into the flexible bag-like body of the present invention. This pump must also be installed at an altitude difference of 10 meters or less from the sea level. Here, the above-mentioned pipeline may be divided into two lines, a water injection line and a discharge line.

FIG. 3 shows an example of an embodiment of the flexible bag-shaped body of the present invention. 7 is a bag filled with compressed air, which is a compressed air pipe strut. It plays the role of shape retention. 8
Is a line for injecting compressed air, and the flexible bag-like body of the present invention is effectively widened by the pipe column into which compressed air is infused to stabilize the shape.

FIG. 4 is a diagram showing another embodiment of the flexible bag-like body of the present invention. The side surface portion 9 of the bag-shaped body has a bellows shape. Therefore, the bottom area can be made constant, and by providing an inlet or outlet for seawater 10 at the bottom surface, the connecting portion between the bag and the pipeline does not move even when the amount of seawater in the bag changes. Therefore, fatigue caused by bending can be reduced. Further, for a large bag-shaped body of the present invention such as Lake Biwa, a rubber-reinforced fabric having a thickness of 3 to 5 cm is used. In addition, the joint portion can be prevented from flowing out of the seawater by reinforcing it with double or triple layers.

The method of adjusting the water level in a lake by injecting seawater into the flexible bag-like body of the present invention utilizes abundant seawater regardless of weather conditions, and the difference in specific gravity between fresh water and seawater. Therefore, there is an advantage that the bag-shaped body can be stably installed at the bottom of the lake without applying a large external force. Also, the scale of water level adjustment can be increased by increasing the number of flexible bags. Further, since the bag-shaped body of the present invention has a compressed air injection pipe strut to stabilize the shape of the bag-shaped body, the bag-shaped body is partly flexible because it has flexibility at the time when the amount of seawater at the time of draining seawater is reduced. It is possible to prevent the seawater from being crushed and blocked and it becomes difficult to extract seawater.

[0021]

Next, the present invention will be described in more detail by way of examples.

Example 1 Nylon 6 2520 denier was used as a warp and a weft, and a plain weave fabric having a basis weight of 600 g / m ² was used as a base fabric with a thickness of 5 mm.
Using a rubberized cloth having a thickness of 10 mm, which was sandwiched with chloroprene rubber and vulcanized, a water pillow-shaped flexible bag having a length of 10 m, a width of 5 m and a height of 1 m was prepared. A pipe support for compressed air having a diameter of 10 cm and a length of 10 m was fixed in the longitudinal direction. This bag has a length of 25
m, width 10 m, depth 2 m. Pseudo-seawater having the same composition as seawater was injected into this flexible bag.
When the flexible bag was installed in the pool, compressed air was injected into the compressed air pipe to widen the bag on the lake surface.
After that, as a result of injecting pseudo seawater into the bag, the bag began to sink and could be stably installed at the bottom of the pool.

The air in the compressed air pipe strut may be deflated while observing the sedimentation velocity of the bag-shaped body at the time when the seawater can be injected. By installing this device, the water surface of the pool
Water level rose by about 50 cm.

According to the experimental verification in the first embodiment, it is possible to adjust the desired water level by injecting seawater into a flexible bag-like body, and to use seawater to obtain flexibility. It was confirmed that the bag could be stably installed on the bottom of the water.
It was confirmed that the actual suction of seawater from the Sea of Japan and the injection into the flexible bag-like body were a design issue and could be designed without problems.

[0025]

INDUSTRIAL APPLICABILITY The present invention uses a flexible bag-like body made of a chloroprene rubberized cloth made of a nylon cloth which is strong and durable and abundant seawater. Therefore, in particular, it is possible to deal with the drop in water level to smoothly and stably supply water from lakes, which are important water sources on which many consumers depend, such as Lake Biwa, and to install equipment and methods that can easily adjust the water level. Can be provided.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a lake water level adjusting device of the present invention.

FIG. 2 is a schematic plan view of the lake water level adjusting device of the present invention.

FIG. 3 is an enlarged view showing an example of a flexible bag-like body of the present invention.

FIG. 4 is an enlarged view showing another example of the flexible bag-like body of the present invention.

[Explanation of symbols]

 1: Lake 2: Sea 3: 9: Flexible bag-like body 4: Pipeline 5,6: Pump 7: Pipe-like bag for air 8: Air piping

Claims (12)

[Claims] 1. A pump for injecting or discharging seawater, a pipe for transferring the seawater to the bag, and a flexible bag for storing the seawater. A water level adjusting device for lakes and marshes. 2. The water level adjusting device for lakes and marshes according to claim 1, wherein the pump and the pipe are composed of two lines, an injection line and a discharge line. 3. The water level adjusting device for lakes and marshes according to claim 1, wherein the bag-shaped body is made of a fiber-reinforced composite material. 4. The water level adjusting device for lakes and marshes according to claim 3, wherein the fiber-reinforced composite material is composed of synthetic fibers and a rubber elastic body. 5. The synthetic fiber is a high strength fiber.
Water level adjusting device for lakes and marshes described. 6. The lake water level adjusting device according to claim 1, wherein the bag-shaped body has a bellows shape. 7. The water level adjusting device for lakes and marshes according to claim 1, wherein the bag-shaped body has a shape-stabilizing support member. 8. The water level adjusting device for lakes and marshes according to claim 7, wherein the form stabilizing support member is an air tube. 9. The lake water level adjusting device according to claim 1, wherein the bag-like body is installed at the bottom of the lake. 10. The lake water level adjusting device according to claim 1, wherein the bag-shaped body is engaged with an anchor member. 11. The lake water level adjusting device according to claim 1, wherein the lake is a dam. 12. When adjusting the water level of a lake using the lake water level adjusting device according to any one of claims 1 to 11, the bag and the sea are connected to the bag provided at the bottom of the lake. By the operation of injecting seawater pumped up from the sea into the bag through the pipeline, and the operation of pumping the seawater out of the bag through the pipeline and extracting the seawater into the sea. A method of adjusting the water level in a lake, wherein the water level is adjusted by changing the volume of the bag.