JP2001073415A - Underground reservoir system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an underground reservoir system capable of storing water underground while collecting and purifying the rainwater in a park or the like, and capable of storing the water for a long time while always circulating the water for purification after storing it, and to be efficiently used for irrigation harmonized with the natural surroundings while growing the plants on the ground. SOLUTION: In the ground of a park or the like, a water permeable ground layer 1, a water permeable sheet layer 2, a water collecting and purifying layer 3 formed by depositing the gravel, and an impermeable layer 4 for surrounding the periphery are formed in this order from the top. The water which has infiltrated into the ground layer 1 intrudes the water collecting and purifying layer 3 through the permeable sheet layer 2, and the water is collected by the impermeable layer 4 and passes through the water permeable layer 3 in the horizontal direction. An underground reservoir 5 for storing the water passing through the water collecting and purifying layer 3 is provided under the impermeable layer 4, and the water inside of the underground reservoir 5 is returned to the water collecting and purifying layer 3 by a circulating pump 7a for circulation. Water collecting level formed by the water collecting and purifying layer 3 is adjusted by a water level adjusting valve 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can collect rainwater in parks, playgrounds, parking lots and the like, store it underground, and provide it as emergency water, irrigation water for vegetation, or municipal water in public toilets. To be concerned with underground water storage systems.

[0002]

2. Description of the Related Art A system disclosed in the following publications is known as a system for collecting rainwater and storing it underground using a site such as a park. For example, a concave portion having a predetermined depth is excavated in a road, a number of hollow blocks are arranged in the concave portion, and the hollow blocks are sequentially connected to each other by a communication pipe. By connecting an arbitrary hollow block with the inflow pipe, backfilling the recess and burying the hollow block, an underground water tank with a collection of many hollow blocks is formed under the road,
Collect rainwater from gutters. Install a pump in any hollow block to take out the stored rainwater.

[0003] A layered structure having a plurality of layered portions is formed inside a peripheral wall portion forming a mortar-shaped space underground and spaced apart therefrom to form a mortar-shaped space. A water tank is formed at the bottom, and rainwater that falls between the peripheral wall and the hierarchical structure is collected in the water tank at the bottom.

[0004]

However, in the prior art, since rainwater from a gutter is stored in a large number of hollow blocks buried underground, it can be applied only when the ground surface such as a road or a parking lot is paved. . In addition, it is not possible to secure a large amount of water storage and there is no part for purifying rainwater.

In the conventional example, the underground structure is complicated and the construction cost is high. In addition, since water is not purified after collecting water in the water storage tank, water cannot be stored for a long time.

An object of the present invention is to purify rainwater (including sprinkled water, etc.) in a park, playground, parking lot, or the like, collect water while storing it underground, and circulate water even after storage. It is an object of the present invention to provide an underground water storage system that can always purify and store water for a long period of time, and that is highly efficient and highly utilizable as water for use while cultivating surface vegetation. .

[0007]

SUMMARY OF THE INVENTION The present invention provides a water purifying layer in which a permeable surface soil layer is laid on a site such as a park or a sports ground, a permeable sheet layer is laid therebelow, and gravel is deposited therebelow. A water-impermeable layer surrounding the surrounding area is formed, and water that has penetrated the surface soil layer penetrates through the water-permeable sheet layer into the water-collecting purification layer, is collected by the water-impermeable layer, and traverses the water-collecting purification layer. Underground, and an underground storage tank for storing water passing through the water purification layer is provided below the impermeable layer, and the water in the underground water storage tank is returned to the water purification layer. And circulating means for circulating.

[0008] According to such a facility, rainwater (including sprinkled water, etc.) is purified by permeating and collecting water through the surface soil layer and the water-permeable sheet layer into the water purification layer,
Further, the water is continuously purified by flowing laterally through the water purification layer, and then stored in an underground water storage tank below the water purification layer. Then, the water in the underground water storage tank is repeatedly purified by returning to the water purification layer and circulating, so that the water quality does not deteriorate even when the water is stored for a long time. By collecting water in the underground water collecting and purifying layer, when the surface of the ground is dry, moisture can be naturally supplied to the surface of the ground and healthy vegetation conditions can always be maintained.

By providing a water level adjusting means for adjusting the water collecting level by the water collecting and purifying layer, it is possible to appropriately adjust the water content on the ground surface, and to introduce air from the ground surface to the water collecting and purifying layer by raising and lowering the water level to thereby increase the plant level. Can prevent root rot and improve water quality.

[0010] By providing a water supply system for supplying water in the underground water storage tank as water, the stored water can be used as needed for emergency water, medium water for public toilets, irrigation for vegetation, and the like.

In parks and athletic fields, in addition to the above-mentioned water storage facilities, an underground septic tank for purifying drainage from public toilets and the like, and a sewage treatment apparatus for purifying treated water by discharging it to the surface of the ground and permeating the soil. And an underground water tank for storing the wastewater from the wastewater treatment device, thereby purifying the wastewater and cultivating vegetation while using the water from the underground water tank as the wastewater of a public toilet or the like. be able to.

[0012]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the overall configuration of an example of the system of the present invention applied to a park. This system is roughly divided into a rainwater collecting / reserving section A, a drainage purification section B, and an intermediate water treatment section C, all of which are formed underground on the premises of a park.

The rainwater collecting and storing section A is for collecting rainwater (including sprinkled water and the like) that has infiltrated from the surface of the ground, purifying the collected water, and storing the collected water in a water collecting tank constructed underground. Shows details of the structure. The rainwater catchment storage section A is formed in a vegetation area such as turf, and from the top, a surface soil layer 1, a permeable sheet layer 2,
The water purification layer 3, the impermeable layer 4, and the underground water storage tank 5 are provided.

The surface soil layer 1 is formed by processing soil suitable for vegetation so as to have good water permeability. The water-permeable sheet layer 2 is located between the surface soil layer 1 and the water purification layer 3 and filters rainwater that has penetrated into the surface soil layer 1, and the sediment from the surface soil layer 1 is collected by the water collection purification layer 3. It is intended to prevent intrusion into the inside, and is made of a nonwoven fabric, a mesh sheet, or the like.

The water collecting and purifying layer 3 is desirably formed by depositing gravel. However, waste materials of molded products such as FRP (fiber reinforced plastic), plastic and concrete may be used.

The water-impermeable layer 4 is located between the water collecting and purifying layer 3 and the underground water storage tank 5 and serves as the bottom of the former water-impermeable and the ceiling of the latter. And it extends to the surface of the earth surrounding the water purification layer 3 and has a concave cross section as a whole. That is, the water-impermeable layer 4 rises not only from the entire bottom portion of the water purification layer 3 but also from the periphery of the bottom portion to the surface of the ground. The impermeable layer 4 can be constructed with reinforced concrete, FRP, or the like together with the peripheral wall and the bottom wall of the underground water storage tank 5, but can also be constituted by an impermeable sheet.

Since the water-impermeable layer 4 has such a structure,
Rainwater (including sprinkled water, etc.) that has permeated the surface soil layer 1 penetrates into the water purification layer 3 while being filtered by the water permeable sheet layer 2, and is collected by the water purification layer 3. . A water level adjusting valve 6 is installed at one end of the water purification layer 3 to purify the collected rainwater in the water purification layer 3 and allow the water to flow naturally into the underground water storage tank 5 while adjusting the water level from one end. Have been.

The underground water storage tank 5 is made of reinforced concrete or FR.
It is constructed below the impermeable layer 4 at P or the like, and stores rainwater that is collected by the water purification layer 3 and flows down as described above. The size of the underground water storage tank 5 is, for example, 1,800 mm per year.
Where there is about 70% rainfall,
Assuming that it is about 0 mm / year, in order to provide a capacity that can secure daily water for 200 people for 30 days in an emergency, the water storage amount is 900 m ³ and the water collection area is 715 m ² . The underground water storage tank 5 has an opening 5 on the ground surface for water intake and internal inspection.
a.

In order to circulate the water stored in the underground water storage tank 5 back to the water collecting and purifying layer 3, a circulation pump 7 a is installed in the underground water storage tank 5 on the opposite side of the water level adjusting valve 6 as a circulating means. In addition, a pipe 8 for flowing water pumped by the pump 7 a from the other end opposite to the water level adjusting valve 6 to the water purification layer 3 is provided.

Therefore, in the water collecting and purifying layer 3, the water flows laterally while being purified from the right side to the left side of the drawing, and in the underground water storage tank 5, the water flows from the left side to the right side to circulate. I do. The water in the underground water storage tank 5 is thus always purified by returning to the water collecting and purifying layer 3 and circulating therethrough.

The water level adjusting valve 6 at one end of the water purification layer 3
The water level, that is, the water level in the soil collected above the upper surface of the impermeable layer 4 can be adjusted by adjusting the water level according to the degree of dryness of the ground surface. Can be grown healthy. In addition, the vertical movement of the water level introduces air from the ground surface to the water purification layer 3 to prevent root rot of the plant,
Water quality can be improved.

The water stored in the underground water storage tank 5 is taken in by a water intake pump 7b and filtered to be used as emergency drinking water, sprinkled for vegetation, and used for public toilet D. Used for cleaning water).

Next, the waste water purification processing section B will be described. As shown in FIG. 3, the wastewater purification processing section B is constructed by arranging a merged treatment septic tank (underground septic tank) 9 and a middle water storage tank 10 side by side underground, and merging drainage from a public toilet D and a canteen. As is known, the water is purified in several stages in the treatment / purification tank 9, and the water is further purified in the middle water treatment section C, and then stored in the middle water storage tank 10 as middle water.

The sewage treatment section C pumps up the treated water in the merged sewage treatment tank 9 with a pump 11 and discharges it to the surface, purifies it with a sewage treatment device 12 using soil, and then collects the sewage in a sewage storage tank 10. Next, the structure of the intermediate water treatment device 12 will be described.

As shown in FIG. 4, the intermediate water treatment device 12
A plurality of soil trenches 13 extending long and parallel along the surface of the earth
And a water purification layer 14 formed under the ground under the water.
3 to infiltrate into the ground and collect the permeated water
While collecting and purifying the water, the water naturally flows into the intermediate water storage tank 10.

As shown in detail in FIG. 5, each of the soil trenches 13 is formed such that sand 16 and gravel 17 are deposited on a water-impermeable sheet 15 buried in the ground by bending the periphery thereof upward, and a nonwoven fabric is formed thereon. A water-permeable sheet 18 such as a mesh sheet or a net-like sheet is placed on the surface, and the ground surface thereon is made of a surface soil 19 having good air permeability (good water evaporation), and a sprinkling pipe 20 is buried in a portion where the gravel 17 is deposited. At the end of the water pipe 20, a water level check port 21 protruding to the surface of the ground is provided, and as shown in the figure, a large number of water holes 20a are formed at an angular difference of, for example, 120 degrees on the peripheral wall of the water pipe 20. Is provided.

The water collecting and purifying layer 14 has a flat area extending over the installation area of the entire soil trench 13, and its peripheral portion is bent upward to deposit gravel 23 on an impermeable sheet 22 buried in the ground. Permeable sheet 2 made of non-woven fabric or mesh sheet
4 between the permeable sheet 24 and the soil trench 13 as an improved soil 25.

The water sprinkled from the water sprinkling pipe 20 in the soil trench 13 is purified by the gravels 17 and the water-impermeable sheet 1
5 and overflows into the improved soil 25 and is purified by the improved soil 25 and soil microorganisms. And
Filtered by the water-permeable sheet 24 of the water-collecting / purifying layer 14 and penetrates the gravels 23, the water is collected by the impermeable sheet 22, and flows through the rubble 23 while being purified by the gravels 23. Flows into

The sewage stored in the sewage storage tank 10 is shown in FIG.
As shown in (2), water is sent to the public toilet D elevated water tank 28 by the pump 27 and provided as public water of the public toilet D (wash water). In addition, when the public toilet D is provided with the clean water elevated water tank 29 and the medium water becomes excessive, the medium water storage tank 10
The internal water is pumped up separately by a pump 30 and sprinkled for vegetation or penetrated into the soil using the soil trench 31 and evapo-transpired as safe water by soil or soil microorganisms or irrigated as soil underground water. I do.

Although the above embodiment is applied to a park, it can also be applied to an athletic field (including various stadiums) and a parking lot on an expressway.

[0032]

According to the present invention, rainwater (including sprinkled water, etc.) is purified by permeating the water collecting and purifying layer through the surface soil layer and the water permeable sheet layer to collect water. The water is continuously purified by flowing laterally through the water purification layer, and then stored in an underground storage tank below the water purification layer, and the water in the underground water storage tank is returned to the water purification layer. By recirculating the water, the water is repeatedly purified, so that the water quality does not deteriorate even if the water is stored for a long time. By collecting water at the underground water collecting and purifying layer, when the surface of the ground is dry, moisture can be naturally supplied to the surface of the ground, and healthy vegetation conditions can always be maintained.

By providing a water level adjusting means for adjusting the water level collected by the water collecting and purifying layer, it is possible to appropriately adjust the water content on the ground surface, and to introduce air from the ground surface to the water collecting and purifying layer by raising and lowering the water level to thereby increase the level of the plant. Can prevent root rot and improve water quality.

By providing a water supply system for supplying water in the underground water storage tank as water, the stored water can be used as needed for emergency water, intermediate water for public toilets, irrigation for vegetation, and the like.

In a park, a sports ground, or the like, an underground septic tank for purifying wastewater from a public toilet, etc., a sewage treatment apparatus for discharging treated water to the surface of the ground to permeate soil, and By providing the underground water tank for storing the underground water, it is possible to purify the drainage and cultivate the vegetation while using the water from the underground water tank as the middle water of a public toilet or the like.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a system example of the present invention applied to a park.

FIG. 2 is a sectional view showing a structure of a rainwater collecting and storing part.

FIG. 3 is a cross-sectional view of a wastewater purification processing section and a middle water processing section.

FIG. 4 is a cross-sectional view showing the structure of the wastewater treatment device.

FIG. 5 is a sectional view of a soil trench.

FIG. 6 is a sectional view of a water sprinkling pipe buried in a soil trench.

[Explanation of symbols]

 A Rainwater collection and storage section B Drainage purification section C Intermediate water treatment section D Public toilet 1 Surface soil layer 2 Water permeable sheet layer 3 Water collection and purification layer 4 Impermeable layer 5 Underground water storage tank 5a Opening 6 Water level adjusting valve 7a Circulation Pump 7b water intake pump 8 pipeline 9 merged treatment septic tank (underground septic tank) 10 medium water storage tank 11 pump 12 medium water treatment device 13 soil trench 14 water collecting and purifying layer 15 impermeable sheet 16 sand 17 gravel 18 water-permeable sheet 19 surface layer Soil 20 Watering pipe 20a Watering hole 21 Water level check port 22 Impermeable sheet 23 Gravel 24 Permeable sheet 25 Improved soil 26 Pipeline 27 Pump 28 Middle water elevated water tank 29 Upper water elevated water tank 30 Pump 31 Soil trench

Claims (4)

[Claims] 1. A permeable surface soil layer, a permeable sheet layer underneath, a water purification layer in which gravels and the like are deposited under the permeable soil layer, and an impermeable layer surrounding the underground layer. Forming
The water that has permeated the surface soil layer penetrates into the water purification layer through the water permeable sheet layer, is collected by the water-impermeable layer, and flows laterally through the water purification layer. Below, an underground water storage tank for storing water passing through the water purification layer is provided, and circulating means for returning water in the underground water storage tank to the water purification layer and circulating is provided. Underground water storage system characterized by the following. 2. The underground water storage system according to claim 1, further comprising a water level adjusting means for adjusting the level of water collected by the water purification layer. 3. The underground water storage system according to claim 1, further comprising a water supply system for supplying water in the underground water storage tank as water. 4. An underground septic tank for purifying wastewater from a public toilet, etc., a sewage treatment device for discharging treated water to the surface of the ground and permeating the soil to purify the sewage, and storing the sewage from the sewage treatment device. And a submerged underground water tank.
4. The underground water storage system according to 2 or 3.