FR3060621A1 - REGARDING AVALER WITH A COUPLED TUBE - Google Patents

Abstract

The invention relates to a rainwater collection manhole (1), comprising: - a water collection well, the well comprising a bottom transverse wall (2) and a side wall (3) formed of plastic and having a generally cylindrical shape of revolution, the bottom transverse wall (2) and the side wall (3) delimiting a settling cavity, and an upper opening (4) through which rainwater can enter the interior of the cavity settling tank, and - an elbow tubing (11, 12) providing fluid communication between the settling cavity and the outside of the well in order to allow rainwater to drain out of the manhole (1) after settling, the elbow tubing (11 , 12) comprising a first tubing part (11) having an inlet opening (15) located inside the settling cavity and a second tubing part (12) having an outlet opening (16) located inside the settling cavity. outside of it settling speed, the second part of the tubing (12) extending through a lumen (13) made in the side wall (3) to the outlet opening (16) forming an elbow with the first part of tubing (11).

Description

(54) DOWNSTREAM look with ELBOW TUBING.

(57) The invention relates to a manhole for collecting (1) rainwater, comprising:

- a water collection well, the well comprising a transverse bottom wall (2) and a lateral wall (3) formed of plastic material and having a generally cylindrical shape of revolution, the transverse bottom wall (2) and the side wall (3) delimiting a decantation cavity, and an upper opening (4) through which rainwater can penetrate inside the decantation cavity, and

- a bent tubing (11, 12) ensuring fluid communication between the decantation cavity and the outside of the well in order to allow the drainage of rainwater out of the manhole (1) after decanting, the bent tubing (11, 12) comprising a first part of tubing (11) having an inlet opening (15) located inside the settling cavity and a second part of tubing (12) having an outlet opening (16) located outside of the decantation cavity, the second part of tubing (12) extending through a lumen (13) formed in the side wall (3) up to the outlet opening (16) forming an elbow with the first part tubing (11).

A-A ^ 4

(13

V

DOWNSTREAM LOOK WITH BENT TUBING

GENERAL FIELD OF THE INVENTION

The present invention relates to the field of collecting and filtering rainwater in public space, especially roads.

The invention relates to a downstream manhole which can in particular lead to an underground volume of rainwater drainage, within a reservoir structure.

STATE OF THE ART

It is known to form reservoir structures under the coating layer of roadways or platforms, to temporarily store runoff water flowing on these coatings during bad weather. A pavement equipped with a reservoir structure generally has, under its bituminous covering layer, a porous crushed layer for the storage of water at shallow depth. Rainwater collection is ensured by downcomer manholes located for example on the edge or in the middle of the roadway, forming collection wells. The rainwater thus collected is injected via drainage pipes connected to the drains in the reservoir structure.

Each outfall manhole is generally made up of a series of concrete elements in the shape of a parallelepiped, stacked on top of each other up to the desired height. The concrete elements delimit a decantation cavity capable of containing a volume of rainwater and in which solid materials mixed with the collected water are separated from the liquid phase by decantation. This decantation step avoids damaging or clogging the drainage pipes by limiting the amount of solid matter contained in the drained water.

There are also known pretreatment systems ensuring, in addition to this decantation, the retention of solid matter collected in the well. The interior of the well can thus be fitted with a removable filter, for example a honeycomb filter, making it possible to filter the water entering the drainage pipe. The well can also be fitted with a filter which extends the external structure of the well, constituting a separate volume for collecting solid matter.

However, these pretreatment devices require regular maintenance, which generates additional costs.

There are also downcomer manholes comprising a tubing in the form of a diving elbow or inverted elbow, having a vertical part directed towards the bottom wall of the well and a horizontal part opening out towards the drainage pipe. The end of the vertical part is generally positioned at the level of the volume of rainwater separated from the solid materials after decantation, so as to inject only the liquid phase, freed from the solid materials. Such tubing thus constitutes a simple and effective pretreatment device. On the other hand, it induces new space constraints: the well of the downstream manhole must be wide enough to be able to introduce there, despite the presence of the tubing, a suction pipe for the settled solids and allow maintenance of the downstream manhole . A typical constraint is to allow the passage of a cylindrical suction pipe having an external diameter of 30 centimeters. For this purpose, it is possible to arrange the tubing on one side of the side walls of the well, rather than in a central position.

The transport and installation of a concrete drain hole induces many constraints. On the one hand, the manhole installation process requires successive stages of transport and stacking of the concrete side wall elements. These steps can be tedious and dangerous for operators (weight of the elements, risk of fingers being trapped between successive stacked elements, etc.). On the other hand, it is necessary to pierce an opening in one of the side walls for the passage of the tubing in the shape of a diving elbow or inverted elbow, to insert the tubing the opening and to ensure the seal between walls and tubing. A seal can then be produced at the edges of the opening, for example in fine concrete. But the masonry of such a joint directly on concrete walls requires a certain drying time, and the seal thus produced is not optimal.

SUMMARY OF THE INVENTION

The present invention aims to overcome these drawbacks, in particular by proposing a manhole for collecting rainwater which is easier to transport and install.

This object is achieved in the context of the present invention, according to a first aspect, by means of a rainwater collection manhole, comprising:

a water collection well, the well comprising a transverse bottom wall and a lateral wall formed of plastic material and having a generally cylindrical shape of revolution, the transverse bottom wall and the lateral wall delimiting a decantation cavity, and an upper opening through which rainwater can penetrate inside the settling cavity, and

- a bent tubing ensuring fluid communication between the decantation cavity and the outside of the well in order to allow the drainage of rainwater out of sight after decantation, the bent tubing comprising a first part of tubing having an inlet opening located at the interior of the decantation cavity and a second part of tubing having an outlet opening situated outside the decantation cavity, the second part of tubing extending through a lumen formed in the side wall up to the outlet opening by forming a bend with the first part of the tubing.

Because the side wall is formed from plastic and has a generally cylindrical shape of revolution, this wall can be formed from sections of standard tubes which can be cut to the desired length. The rainwater collection manhole obtained therefore does not require the stacking of concrete elements.

In addition, the drilling of the plastic wall of the manhole is much easier than the drilling of the side walls of the concrete elements, in particular to produce the light and the insertion of the bent tubing.

Furthermore, a manhole according to the invention can be made available with bent tubing preassembled in the factory, no longer requiring a drilling operation when it is installed on the site. As a variant, a manhole and a bent tubing can be made available separately: a hole is then made at the desired height on the side wall, to make a lumen and allow the tubing to be put in place.

The choice of a light and easily transportable material is an attractive alternative to concrete. The transport of the components of the gaze is greatly facilitated. In particular, a look according to the invention is in accordance with the heavy load restrictions which exist in the construction sector.

The gaze can have the following additional characteristics:

- the first part of the tubing is arranged so that the inlet opening is oriented towards the bottom wall of the well without touching it,

- the side wall of the well is formed of a section of plastic tube, preferably of high density polyethylene (HDPE),

- the side wall is formed of a section of corrugated tube,

- a first seal is placed between the second part of the bent tube and the side wall of the well, over the entire perimeter of the lumen, this seal being able to be made of rubber,

- the light made in the side wall has a diameter between 16 and 20 centimeters,

- the bent tubing comprises a second seal, disposed between the first part of tubing and the second part of tubing at the elbow,

- the side wall and the bent tubing are arranged relative to each other so as to allow the passage of a tubular instrument 30 centimeters in diameter, through the upper opening to the bottom wall of the well ,

- the manhole further comprises an adaptation piece closing the upper opening of the manhole, this part making it possible to place a metal grid on the manhole allowing the flow of rainwater,

- this adaptation piece comprises two support pieces each having a free edge, the free edges of the support pieces defining an opening intended to be covered by the metal grid, the metal grid coming to bear on the edges of the support pieces,

- the adaptation piece also comprises two reinforcing pieces each arranged in contact with an internal face of one of the support pieces, each reinforcing piece being arranged perpendicular to the support piece,

According to a second aspect, the present invention provides an assembly comprising a manhole for collecting rainwater, and a plug intended to temporarily close the upper opening, during the installation of the manhole.

According to a third aspect, the present invention provides a method for installing a manhole for collecting rainwater, comprising the steps of:

clearing of a layer of soil, depositing the well, partial backfilling with aggregates intended to form a reservoir structure under a roadway or a platform around the well, connection of the second part of bent tubing to a hydraulic rainwater drainage network towards the reservoir structure, completion of the backfill with aggregates.

Furthermore, the invention also relates to an assembly comprising a manhole as defined above, and a plug intended to temporarily close the upper opening during installation of the manhole.

PRESENTATION OF THE DRAWINGS

Other characteristics and advantages will also emerge from the description which follows, which is purely illustrative, and not limiting, and should be read with reference to the appended figures, among which:

FIG. 1 schematically represents, in top view, a downstream manhole in accordance with an embodiment of the invention, installed on site, the upper opening of the manhole being left free,

FIG. 2 schematically represents the downstream manhole of FIG. 1, left open on its upper opening, and connected by the external open end of its bent tubing to a drainage pipe,

FIG. 3 schematically represents, in side view along an axis of vision contained in the plane A-A, the downstream view of FIG. 1,

FIG. 4 schematically represents, in cross-section view along the plane A-A, the downstream view, the section plane passing through the bent tubing,

FIG. 5 schematically represents, in cross-section in three dimensions, the downstream look and indicates the positioning of the bent tubing,

FIG. 6 schematically represents, in cross section along the plane A-A, an adaptation piece for the upper opening of the manhole, adapted to receive a grid on its upper part,

FIG. 7 schematically represents the adaptation piece, seen from above along an axis of vision contained in the plane A-A,

- Figure 8 shows schematically, the adaptation piece, in view of three quarters in three dimensions,

FIG. 9 schematically represents a plug adapted to fill an upper opening of the manhole, in side view in cross section along the plane A-A,

FIG. 10 schematically represents the plug, seen from above along an axis of vision contained in the plane A-A,

FIG. 11 schematically represents the plug, with a view to three quarters in three dimensions,

FIG. 12 schematically represents an adaptation piece for a metal grid, seen from above, installed on the manhole,

- Figure 13 shows schematically, in side view, the manhole equipped on an upper opening with a plug,

- Figure 14 shows schematically, in side view, the manhole, where the cap is partially raised to glimpse the upper opening of the manhole.

DETAILED DESCRIPTION OF AN EMBODIMENT

In Figures 1 to 5 and Figures 12 to 14, the manhole for collecting rainwater 1 has a generally cylindrical shape of revolution.

In FIG. 1, the gaze 1 is placed vertically, in a soil composed of aggregates, here porous crushed. Figure 2 gives an enlarged view of the manhole 1, connected to a tubular pipe 7 made of corrugated high density polyethylene (HDPE), ensuring the connection with a hydraulic network. Line 7 allows the rainwater collected in manhole 1 to be injected into the surrounding reservoir structure in porous crushed form. One function of the aggregate layer which surrounds the manhole 1 is to temporarily store water, for example during bad weather.

With reference to FIGS. 3 to 5, the manhole 1 comprises a side wall 3 of constant cross section, and a transverse bottom wall 2 in the form of a solid disc which fills a lower opening in the side wall 3. The cylindrical volume formed by the wall bottom 2 and the side wall 3 constitutes a rainwater collection well.

The bottom wall 2 is a solid disc filling the entire space of the lower opening of the side wall 3. The side wall 3 is here in one piece, and can be obtained for example by section of a cylindrical tube perpendicular to its axis of revolution. Thus, obtaining the side wall 3 does not require cutting and stacking of several elements. A material of the bottom wall 2 and the side wall 3 is here high density polyethylene (HDPE). The side wall 3 is made of corrugated HDPE. This material, light and flexible, also has mechanical strength and durability which make it very suitable for this use. The choice of a corrugated material is suitable for the side wall 3, which is thus stiffened and not very sensitive to longitudinal deformations, while being light.

An upper opening 4 of the side wall 3 is left free, and is not closed by a wall, unlike the lower opening of the side wall 3 which is closed by the bottom wall 2.

Dimensions of the side wall 3 are for example the following: 620 millimeters in external diameter, 500 millimeters in internal diameter, and 1200 millimeters in length. The corrugated HDPE wall thus has a maximum thickness of 40 millimeters. The well bottom wall 2 is here 15 millimeters thick.

The side wall 3 of the well and the transverse bottom wall 2 form, within the manhole 1, a cavity of cylindrical shape called “decantation cavity” of rainwater. Rainwater can pass through the upper opening 4 during inclement weather, either by falling directly into the decantation cavity, or by runoff from neighboring surfaces on the ground surface where the manhole 1 is practiced, and occupy a certain volume of the settling cavity.

In addition, this downstream manhole has a device for pretreating rainwater collected in the well formed by the bottom wall 2 and the side wall 3, in the form of a bent tube 11, 12. This bent tube comprises a first tubing part 11, vertical when the manhole 1 is vertical, and a second part of tubing 12, horizontal when the manhole 1 is vertical.

The second part of tubing 12 is here of constant cross section and of axis perpendicular to that of the downstream manhole. This second part of tubing protrudes from the cylindrical wall 3 of the manhole, by an end 16 which constitutes an outlet opening of the bent tubing 11, 12. A lumen 13 is drilled in the side wall of well 3 to allow positioning vertical and the passage of the second part of tubing 12. This light 13 can be already made in a preassembled manhole 1 made available, preferably with a bent tubing 11, 12, or can be cored when a manhole is placed at the desired height for the passage of the second part 12 of tubing.

The first part of tubing 11, connected by an elbow to the second part of tubing 12, is of constant section, and of axis of revolution parallel to the side wall 3 of the manhole. It has a lower end 15 which constitutes an inlet opening for the bent pipe 11, 12. The lower end 15 is oriented towards the well bottom wall 2 and opens out above the well bottom wall 2.

The manhole 1 is seen in FIG. 3 from the side of the outlet opening 16, along an axis of vision coinciding with the axis of central symmetry of the part 12 of the bent tube. The viewing axis is perpendicular to the axis of revolution of the side wall 3 of the manhole, which corresponds to the plane A-A. The same look is seen in cross section in Figure 4. The section plane AA, which is a plane of symmetry of the bent tube 11, 12 is shown in Figure 3. Finally, Figure 5 illustrates this same look seen from the side where the bent tubing 11, 12 projects from the side wall 3, in partial section where the position of the bent tubing 11, 12 has been shown.

The second part of tubing 12 projects from the external surface of the side wall of well 3, for example over a length of 150 millimeters. The first part of tubing 11, meanwhile, extends along the side wall of well 3, for example over a length of 250 millimeters, between the highest point of the elbow and the low end opening out above of the well bottom wall 2.

The bent tubing 11, 12 is here arranged at 340 millimeters from the side wall part directly opposite the tubing. In other words, the bent tubing 11, 12 is located at a maximum distance of 340 millimeters from the internal face of the cylindrical wall 3. Thus, a vertical tube with an axis parallel to that of the downstream manhole, and of external diameter less than 340 millimeters, can be introduced vertically through the opening 4 to the bottom wall of the well 2. In particular, it is possible to pass a suction tube into the manhole well 1 to maintain the manhole and vacuum the solid matter retained at the bottom after drainage of the settled rainwater.

Furthermore, the first part of tubing 11 is here glued to the internal face of the side wall of well 3, in order to limit the bulk and provide the largest possible space for the passage of a suction pipe in view. of the interview.

The lumen 13 formed in the side wall 3 of the well is here fitted, over its entire perimeter, with a seal 14. The seal 14 is put in place between the second part of tubing 12 and the side wall 3 of the well . The seal 14 is preferably made of rubber. A joint used as standard in the field of road improvements, such as a Forsheda or Polieco joint, can be used here. The assembly formed by the side wall 3 of corrugated HDPE, the bent tubing 11, 12 and the seal 14 is tight and allows the retention of rainwater contained in the well.

The dimensioning and the relative positioning of the side wall 3 of the well and the bent tubing 11, 12 is provided so that the inlet opening 15 of the tubing is positioned at the level of the liquid phase of rainwater separated from the materials solids after decantation, to allow only the said liquid phase to be drained, and so that the outlet opening 16 is positioned at a height which allows connection to a drainage pipe external to the manhole 1.

The bent tubing thus constitutes a device for pretreatment of collected rainwater, which is very advantageous here. Indeed, the height between the lower end 15 of the second part of tubing 11 and the well bottom wall 2 provides a large volume to allow the settling of rainwater. It is expected that a layer of coarse solid material will form at the bottom of the manhole, surmounted by a certain height of volume of rainwater after decanting to recover and reinject into the reservoir structure. On the one hand, the layer of solid material formed at the bottom of the well is not restored out of sight (but is therefore to be cleaned elsewhere), and on the other hand, if a layer of fine and floating waste is formed at the -above the volume of rainwater after decantation, this layer also does not enter the second part of tubing 12

In the absence of a second part of tubing 12, that is to say in a conventional downstream manhole without plunger elbow, said layer of floating solid material would be easier to be drained at the same time as rainwater. There would be no pre-filtration before the drainage of the collected rainwater.

FIGS. 6 to 8 show a cylindrical adaptation piece 5 capable of closing the upper opening 4 of the manhole 1. This adaptation part makes it possible to place a metal grid, external to the manhole 1, on the manhole 1 when the latter is positioned substantially vertically, like a standard sewer grate.

Adapter 5 is cylindrical in shape. It comprises a side wall 51 which delimits a non-obtuse circular lower opening, so that the side wall 51 of the adaptation piece 5 can come into contact with the side wall 3 of the manhole 1 when the adaptation piece 5 is placed above manhole 1 at its upper opening 4.

The side wall 51 further delimits a circular opening partially closed by two support pieces 52. Each of these two support pieces is in the form of a thin plate, one external edge of which is an arc of a curvature of curvature. adapted to abut against the side wall 51, and of which another external edge is straight. This last outer edge forms a free edge for the support pieces 52. The support pieces 52 are here of identical shape, and positioned symmetrically with respect to a diameter of the upper circular opening of the adaptation piece 5, so that the two straight free edges of the two support pieces 52 delimit an opening 54 in length, which can be filled by a lower part of a metal grid.

The adaptation piece 5 further comprises two reinforcing pieces 53. Each of these reinforcing pieces is positioned on an internal face of one of the support pieces 52, namely the face which is not intended to be in contact with a lower part of a metal grid positioned above the manhole 1. Each reinforcing part 53 takes the form of a thin plate whose edge is positioned on the internal face of the corresponding support part 52, perpendicular to said internal face. Each reinforcement piece 53 is positioned parallel to the free edge of the support piece 52 on which it is placed, and is assembled by welding to said support piece. The reinforcement piece 53 is positioned with a slight setback, for example 30 mm, relative to the free edge of the support piece 52.

Here, an internal diameter of the side wall 51 is 580 millimeters, to allow good wedging of the adaptation piece 5 on the side wall 3. The side wall 51 is 170 millimeters high, and the support pieces 52 which delimit its upper opening are 20 millimeters thick. Finally, the reinforcement pieces 53 are 20 mm thick and 50 mm wide. The opening 54 formed by the straight free edges of the support pieces 52 is 210 millimeters wide.

The adaptation piece 5 can thus be positioned, once the installation of the manhole 1 is finished, on the upper opening 4 of the manhole 1, in a removable manner. A metal grid such as a sewer grid can then be positioned on the adaptation piece 5.

There is shown, in Figures 9 to 11, a plug 6, of cylindrical shape, configured to close the upper opening 4 of the side wall 3. The plug 6 is also suitable for closing any opening which would be made in the side wall 3 according to a plane of section perpendicular to the plane AA.

The plug 6 is also of cylindrical shape. It has a side wall 61, providing a bottom opening 62 which is not closed to allow, as for the adaptation piece 5, direct contact between the side wall 61 and the top of the side wall 3 of the manhole 1, when the plug 6 is positioned so as to close the upper opening 4. On the other hand, an upper opening of the plug 6 is closed by an upper face 63 in the form of a solid disc.

Dimensions of the plug 6 are here as follows: 170 millimeters in height for the side wall 61, 15 millimeters in thickness for the upper face 63.

Thus, when the plug 6 is positioned on the upper opening 4 of the manhole 1, the inside of the manhole 1 and in particular the decantation cavity formed by the side wall 3 and the bottom wall 2 are no longer accessible. Such a plug is therefore of advantageous use during a phase of laying the manhole, where the side wall 3 is already in place but not blocked on its upper opening 4. Risks of falling of people or objects in the manhole 1, up to the bottom wall 2, are thus avoided.

In FIG. 12, the manhole 1 is presented in top view, is placed along a vertical axis on the ground, and surmounted by the adaptation piece 5. The second part of tubing 12, and the bottom wall 2, are visible through opening 54.

In FIGS. 13 and 14, the manhole 1 is shown when its upper opening 4 is closed by a plug 6. While in FIG. 13 the plug 6 is positioned normally and hides the upper opening 4, in FIG. 14, the plug 6 is raised to allow a glimpse of part of the upper opening 4.

The installation of manhole 1, in combination with an appropriate reservoir structure to ensure temporary storage of collected rainwater, is simple. It is first necessary to clear the ground, to a height sufficient to allow the side wall 3 and the bottom wall 2 of the well to be buried. The well is then laid on the ground, and the land surrounding the well is partially backfilled. At this stage, the backfill is carried out with a layer of aggregates, intended to form a reservoir structure around the manhole 1, under a roadway or a roadway platform. A porous crushed material can be used for this backfill. If necessary, a coring of the side wall 3 can be carried out in order to make a hole 13 of adequate size for the passage of the second part of bent tubing 12 (here, the hole 13 is a circular hole with a diameter of 160 millimeters). Alternatively, the side wall 3 that is installed can already be provided with a light. The angled tubing 11, 12 can be made available with the walls 2 and 3 of the well, and can be installed when the manhole 1 is placed.

At this stage, if the installation of the manhole 1 is interrupted before its end, the plug 6 can be placed to close the upper opening 4 of the manhole and prevent risks of falling or damaging the parts of the manhole.

To complete the installation of manhole 1, the second part of tubing 12 is connected to a drainage pipe. The decantation cavity is thus placed in fluid communication with a point in the water network, which makes it possible to route the decanted rainwater to the reservoir structure. The backfilling is then completed, always with material capable of constituting a reservoir structure such as aggregates.

Finally, when the embankment is completed and the manhole 1 in place on the ground, the adaptation piece 5 can be arranged to close the upper opening 4 of the manhole 1. A grid, such as a metal sewer grid, can then be disposed above the adaptation part 5, and in particular on the opening 54 formed in the adaptation part 5. It is this grid which is in contact with the surface of the ground and in the open air, once the gaze finished.

The adapter 5, and such a grid, are removable and can easily be removed to gain access to the interior of the well and to the settling cavity. In particular, it is necessary to maintain the decantation cavity regularly to remove the solid matter collected there and separated from the decanted rainwater. The manhole 1 is thus preferably designed to allow the passage of a tubular structure, such as a suction tube, which can be inserted through the upper opening 4 up to the bottom wall 2 of the well, to collect the solid materials deposited. at the bottom of the well.

The method of installing such a manhole is thus simplified compared to the installation of a concrete drain manhole, for which it would be necessary to stack concrete elements to form side walls of wells. Not only is the handling and transport of such elements tedious and dangerous, but in addition, it can be complex to ensure good sealing at the interface of the stacked elements, and between the side walls thus formed and the bent tubing (in particular at the level of the light used to let a drainage pipe pass). Masonry must then be made to manufacture seals, with non-optimal efficiency.

Claims (14)

1. Rainwater collection manhole (1), comprising: - a water collection well, the well comprising a transverse bottom wall (2) and a lateral wall (3) formed of plastic material and having a generally cylindrical shape of revolution, the transverse bottom wall (2) and the side wall (3) delimiting a decantation cavity, and an upper opening (4) through which rainwater can penetrate inside the decantation cavity, and - a bent tubing (11, 12) ensuring fluid communication between the decantation cavity and the outside of the well in order to allow the drainage of rainwater out of the manhole (1) after decanting, the bent tubing (11,12) comprising a first part of tubing (11) having an inlet opening (15) located inside the settling cavity and a second part of tubing (12) having an outlet opening (16) located outside the decantation cavity, the second part of tubing (12) extending through a lumen (13) formed in the side wall (3) up to the outlet opening (16) forming an elbow with the first part tubing (11). 2. Manhole according to claim 1, wherein the first portion of tubing (11) is arranged so that the inlet opening (15) is oriented towards the bottom wall (2) of the well, without touching the wall of bottom (2). 3. Manhole according to one of claims 1 and 2, wherein the side wall (3) is formed of a section of plastic tube. 4. Manhole according to one of claims 1 to 3, wherein the side wall (3) is formed of a section of corrugated tube. 5. Manhole according to one of claims 1 to 4, further comprising a first seal (14) disposed between the second part of the bent tube (12) and the side wall of well (3) and extending all around the perimeter of the light (13). 6. Manhole according to claim 5, wherein the first seal (14) is rubber. 7. Manhole according to one of claims 1 to 6, in which the light (13) formed in the side wall (3) has a diameter between 16 and 20 centimeters. 8. Manhole according to one of claims 1 to 7, wherein the bent tubing (11,12) comprises a second seal, disposed between the first part of tubing (11) and the second part of tubing (12) . 10. Manhole according to one of claims 1 to 9, wherein the side wall (3) and the bent tube (11,12) are arranged relative to each other so as to allow the passage of a tubular instrument 30 centimeters in diameter, through the upper opening (4), to the bottom wall (2) of the well. 11. Manhole according to one of claims 1 to 10, further comprising an adapter piece (5) adapted to close the upper opening (4) and to receive a metal grid allowing the flow of rainwater through the wire rack. 12. Manhole according to claim 11, wherein the adaptation piece (5) comprises two support pieces (52), each support piece having a free edge, the free edges of the support pieces defining an opening (54) intended to be covered by the metal grid, the metal grid coming to bear on the edges of the support pieces (52). 13. Manhole according to one of claims 11 and 12, wherein the adapter piece (5) further comprises two reinforcing pieces (53) each disposed in contact with an internal face of one of the support pieces ( 52), each reinforcement piece (53) being arranged perpendicular to the support piece. 14. An assembly comprising a manhole according to one of claims 1 to 13, and a plug intended to temporarily close the upper opening during installation of the manhole. 15. Method for installing a manhole according to one of claims 1 to 4413. comprising the steps of: - clearing of a layer of soil; - removal of the well (3), - partial backfilling with aggregates intended to form a reservoir structure under a roadway or a platform, around the well; - connection of the second part of bent tubing (12) to a hydraulic network for draining rainwater towards the reservoir structure; 5 - finishing of the backfill with aggregates.