FI75018C - Percolating storm water well and ways of producing it - Google Patents

Description

1 75018

Filterable rainwater well and its method of manufacture

The present invention relates to a filterable surface water or rainwater well comprising a well body placed in a tank consisting of a substance to be filtered, e.g. crushed stone, having a diameter considerably smaller than the diameter of the tank and provided with an overflow pipe. The invention also relates to a method of manufacturing such a filterable surface water well.

In conventional surface water treatment, essentially all of the rainwater is directed to the recipient. Rainwater is collected in street wells that are sealed and connected to large pipelines. As street wells are built, the pipe dimensions will increase even more. At the same time, the rainwater that would be needed to form groundwater where the rain has come is drained away. This technique is therefore being abandoned, and instead rainwater (surface water) is collected locally in large tanks on street or park land, where the water is filtered and / or stored for some time before draining.

U.S. Patent 4,031,009 discloses an example of a surface water well consisting of a stone tank and a well body disposed therein, the jacket surface of which is partially perforated to allow water to enter the tank. As rainwater brings sand and other objects down into the well, the well body fills over time with sand and objects. Once the sand has reached the level on the casing surface of the well body at which the perforation begins, the sand flows out into the tank, which gradually becomes clogged and thus becomes unusable. This well therefore requires close monitoring of the sand level in the well body and frequent cleaning of the well body. Since the entire jacket surface of the well body cannot be used as a drainage point for the tank, a rather large well body is needed to obtain a sufficiently large, perforated surface.

2 75018

The object of the present invention is to provide a surface water well of the type mentioned at the beginning, which eliminates the disadvantages of the previously known well.

Another object of the invention is to provide a method of manufacturing this well.

The above-mentioned objects are achieved according to the invention by a filterable surface water well, the characteristics of which are apparent from the characterizing part of the following claim 1, and by the method of manufacturing this well, which is characterized by the features set forth in the characterizing part of claim 5.

The present invention increases the possibilities for local treatment of surface water because the immediate vicinity of the surface water well is used as a reservoir and thus as an infiltration area. The number of wells in the street is large, which makes the total infiltration considerable.

The invention makes it possible to reduce the dimensions of the pipes, which is very important economically, partly to simplify the installation work, because the well is prefabricated and smaller than conventional surface water wells, partly allows smaller excavation than before and drains surface water into underground pipelines and

The invention will now be described in more detail by means of exemplary embodiments with reference to the accompanying drawing.

Figure 1 shows a vertical section through a surface water well according to the invention.

Figure 2 shows a section along the line II-II in Figure 1.

Figure 3 shows a modified embodiment of a well overflow pipe.

li 3 75018

Figure 1 shows a well body 1 of prefabricated products, for example concrete and placed in a container 8 made of a desiccant, e.g. self-compacting crumb products, preferably crushed stone. Both the casing surface and the bottom of the well are perforated, which are distributed over the entire lowered surface of the well body. The diameter of the well body is considerably smaller than the diameter of the tank 8, which makes the well drawable and the surface water can be filtered into the soil surrounding the well by means of intermediate storage of water in the tank 8.

In order to prevent the ingress of fine particles entrained in the well with the surface water, e.g. sand, into the tank, this is surrounded by a water-permeable nonwoven fabric 10, 11, e.g.

The nonwoven fabric also prevents mixing of the contents of the tank and the base. In the embodiment shown in the figure, a relatively large hole is first dug in the ground with respect to the well body 1. The nonwoven fabric 10 is then placed in a hole so that the fabric completely covers its walls, making the fabric so large that a strip 12 is formed on the ground. The prefabricated well body 1 is provided with a water permeable nonwoven sock 11 covering all holes in the well body to cover the bottom, after which the sock body with the sock is placed on top of the tank material. The hole is then filled with tank material up to the top of the well body. The strip 12 is folded in against the well body 1 and connected to the sock 11 to form a closed container 8. The manhole cover 4 or cover is placed on top of the well body, and a coating agent 9 is placed on top of the container.

The well according to the invention is provided with an overflow pipe 3a 4 75018 (Figures 1 and 2) or 3b (Figure 3). Figures 1 and 2 show an overflow pipe consisting of a vertical pipe 3a detachably placed in the well body 1, the lower part of which is bent and led out through the well body to be connected to the surface water pipe 7. If desired, the flow level of the overflow pipe can be reduced by removing the pipe 3a from the well body 1 and cutting it to the desired level and placing it back in the well. The mouth of the pipe 3a is closed by a cover 5 provided with floats and articulated to the pipe, well body wall or cover 4, whereby the overflow is opened to drain excess water into the surface water pipe 7 when the water in the well body raises cover 5. air flow through the overflow is prevented.

Figure 3 shows an overflow 3b comprising a flat, vertical wall dividing the well body into a main part and an overflow part.

Il

Claims (5)

A percolating storm water well comprising one in one of a drainage material, e.g. macadam, retaining magazine (8) reduced well body (1), the diameter of which is considerably smaller than the diameter of the magazine and which is provided with a drain outlet (3a), characterized in that the entire magazine (8) is enclosed by a water-permeable cloth (10). 11, 12), which prevents the ingress of sand and other articles into the magazine from the well body (1) or from the surrounding soil; that the main body surface and bottom of the well body are perforated (2); and that the drain outlet is a vertical tube extending into the well (3a, 3b). 2. A well as claimed in claim 1, characterized in that the drain drain is a tube (3a) arranged in the well body (1). A well according to claim 1, characterized in that the overflow drain (3b) is formed by a part of the casing surface (1) of the well body (1) and a vertical wall in the well body. 4. A well as claimed in any one of claims 1-3, characterized in that the upper orifice of the overflow drain (3a, 3b) is closed by a cover (5), which is lifted to release the orifice when the water level in the well body (1) when a predetermined level. 5. A method of preparing a percolating storm water well which comprises one in a drainage material, e.g. macadam, resistant reservoir (8) well body (1), the surface of which is at least partially perforated (2), in which way a heel, the dimensions of which are considerably larger than the dimensions of the well body, is absorbed into the ground.