CN106013386A - Serially-connected multi-level-rain-garden permeation system for existing residential areas - Google Patents

Abstract

The invention discloses a continuous multi-level rainwater garden infiltration system in an existing residential quarter, which includes: multiple roof gardens, multiple downpipes, multiple first-level rainwater gardens, multiple low-potential cluster central green spaces, and multiple second-level rainwater gardens. Second-level rain gardens, the elevation of the first-level rain gardens is higher than the elevation of the second-level rain gardens, and the elevation of the second-level rain gardens is higher than the elevation of the third-level rain gardens. Advantages of the present invention: the rainwater is infiltrated into the ground through infiltration facilities such as multi-level rainwater gardens, low-level green spaces, and shallow vegetation trenches, thereby replenishing groundwater resources; the infiltration of rainwater into the ground reduces ground runoff, thereby alleviating flood disasters In the process of rainwater infiltration, the soil plays a purifying function; low-lying green spaces, shallow vegetation trenches, and rain gardens all purify rainwater runoff. These purification functions can reduce pollution problems in surface water systems.

Description

Continuous multi-stage rain garden infiltration system for existing residential quarters

technical field

The invention relates to a rainwater garden infiltration system, in particular to a rainwater pipeline discharge system in an existing residential area.

Background technique

At present, the drainage of rainwater in residential quarters is mainly realized by laying underground rainwater pipelines, which is the technical method of rainwater engineering planning adopted by various design institutes. Generally by the following steps:

① Estimation of rainfall

The rainwater pipeline drainage technology first uses the relationship function between the rainstorm intensity q, the rainfall duration t and the return period p, that is, the rainstorm intensity formula to calculate the rainstorm intensity, and then uses the rainstorm intensity, runoff coefficient and catchment area to estimate the rainfall in the planning area .

②Arranging rainwater underground pipelines

According to the predicted amount of rainwater, combined with the current terrain elevation slope, the pipe diameter and slope of the rainwater pipeline are reasonably determined. Then, according to the planning and layout of the residential area, rainwater underground pipes are laid under the roads of the group and the community, and the rainwater is discharged from the inside of the community through the pipeline system to the rainwater municipal pipe network outside the community. Finally, the rainwater is directly discharged into surface water systems such as rivers and lakes.

The existing rainwater pipeline drainage technology in residential areas has the disadvantages of wasting rainwater resources, aggravating flood disasters, and polluting surface water systems.

details as follows:

①Waste of rainwater resources

For cities, rainwater is an ideal water source for low-quality water. Rainwater is lightly polluted water, which contains less organic matter, less total hardness, and high dissolved oxygen content; and the rainwater purification process is simple, the treatment cost is lower than that of sewage, the pollution rate of bacteria and viruses is lower than that of sewage, and rainwater reuse Compared with sewage purification, the public acceptance is higher, so rainwater purification can be used for domestic miscellaneous water, industrial water, etc., which is one of the effective ways to solve the shortage of water resources in our country. However, the rainwater pipeline drainage technology currently used in residential quarters "discharges" all the rainwater, resulting in a large waste of rainwater resources.

② Exacerbation of flood disasters

In the current rapid urbanization process in my country, the scale of urban land use has increased sharply, and with the increasing proportion of impermeable and hardened pavement on the ground, most of the rainfall that should have penetrated into the ground has been transformed into surface runoff. However, the pipe discharge technology adopted in residential areas usually adopts cement pipes, which changes the form of open ditch for seepage vegetation in the past, so that the runoff does not have any seepage reduction in the process, and promotes the formation of flood peaks. In addition, the surface water system before urbanization has been largely landfilled during the urbanization process, resulting in the lack of surface water bodies for rainwater storage in residential areas.

③Aggravate the pollution of surface water system

Stormwater runoff pollution is one of the important sources of surface water system pollution in cities, and is even listed by the U.S. Environmental Protection Agency as the third largest source of pollution in rivers and lakes in the United States. The rainwater pipeline drainage technology in existing residential areas usually adopts the method of collecting rainwater at the rainwater outlet and discharging it through the rainwater pipeline. The rainwater runoff carries a large amount of pollutants during the confluence process, such as hydrocarbons, heavy metals, oil pollution from vehicles, and pedestrians throwing it away at will. litter, debris and pollutants washed out from paved landscaping, etc. These impurities make the rainwater runoff seriously polluted, and the polluted rainwater runoff is discharged to the surrounding water bodies through the stormwater outlet and the rainwater pipeline system. This process carries the garbage accumulated in the stormwater outlet, causing the water environment of urban rivers and lakes to deteriorate.

④ Large investment in infrastructure

In response to the increasingly frequent occurrence of flood disasters, the existing rainwater pipeline drainage technology in residential areas emphasizes the stormwater response strategy of "increasing the return period and increasing the diameter of the rainwater pipe to achieve rapid discharge". According to the latest edition of "Outdoor Drainage Design Code 2011 Edition" GB50014-2006 on the return period requirements, more than half of the design return period in my country's cities currently cannot meet the standard. If we only rely on "increasing the diameter of rainwater pipes" to alleviate flood disasters, then almost all cities in our country will need to abandon the existing rainwater pipe systems and lay new enlarged rainwater pipes, which will bring financial losses to cities. Heavy burden.

The system disclosed in the Chinese patent titled "An Ecological Road Impact-resistant Rainwater Utilization System" includes stormwater outlets, abandonment troughs, low-lying green spaces, initial rainwater storage and treatment wetlands, overflow wells, rainwater pools, rainwater utilization structures and Drainage well; there is a grid in the rainwater outlet, and there is a volume space for rainwater to stay for a short time and a grit chamber inside. The rainwater outlet is connected to the abandonment trough through the rainwater pipe; an overflow port is provided on the top of the abandonment trough. The trough is connected to the initial rainwater storage and treatment wetland through the waste flow pipe; the lower low-level green space is lower than the road surface, and a permeable backfill layer is provided under the lower low-level green space; the initial rainwater storage and treatment wetland includes the initial rainwater storage pool and treatment wetland, and the initial rainwater storage pool There is a partition wall with water distribution holes between it and the treatment wetland.

This invention mainly focuses on the utilization of rainwater on the green belt beside the road, and focuses on the initial waste flow and infiltration utilization of rainwater on heavily polluted urban roads. Combine. The set open rainwater pool is neither suitable for use in the northern region with insufficient rainfall, and its landscape effect is also poor in northern winter.

The system disclosed in the Chinese patent titled "Urban Rainwater Drainage System" includes a rainwater well placed under the asphalt road and close to the curbstone. It is connected with the upper part of the inspection well. The inspection well is a part of the sewer. The sewer is parallel to the road. The seepage well is directly inserted into the ground. There is a movable inspection well cover on the inspection well, and the drain pipe is at an angle of 15 to 25 degrees to the sidewalk.

The invention patent focuses on the initial ecological discharge of road rainwater and the rainwater infiltration of pipelines. There is no content involved in the application of the community; the combination with greening is not considered, and it is not suitable for the transformation and application of the existing community.

The system disclosed in the Chinese patent titled "A baffle-type water-holding garden system for treating rainwater collected in urban residential quarters" includes a baffle-type water-holding area arranged in a low-lying green space. One side of the diversion-type water holding area is flush with one side of the low-lying green space and an overflow outlet is provided; an annular sump surrounds the left, lower and right sides of the diversion-type water retention area; The outer wall of the edge of the low-lying green space is provided with a plurality of water inlet gaps, and the inner wall of the ring-shaped sump near the left side of the baffle-type water-holding area is provided with a water-holding area water inlet; Planted areas with covered deflected water holding areas.

The invention patent focuses on the deflected treatment of rainwater in the residential area through the garden. The focus is on the low-lying green land through the deflected method to prolong the rainwater flow time, increase infiltration and reduce the erosion of vegetation. There are still deficiencies in the combination with the multi-level greening layout system of the community. It is not suitable for simple reuse in a large community, and there is no consideration for the connection with the overall traffic mode of the community.

The system disclosed in the Chinese patent titled "Green Community Shock Resistant Rainwater Ecological Utilization System" includes building rainwater pipes, drainage ditches, abandonment wells, infiltration wells, low-lying green spaces, grass-planting shallow ditches, landscape water bodies, pumps, distribution Water mains and ground water hydrants. The rainwater ecological utilization system infiltrates rainwater from the roof of the building through rainwater pipes, drainage gutters and abandonment wells into infiltration wells, then enters the landscape water body through shallow vegetation ditch for purification and storage, and finally passes through pumps, water distribution pipes, water supply Bolts form a complete rainwater utilization system.

This invention mainly emphasizes "rainwater reuse system" at first, and this reuse system is not suitable for the condition of less rainfall in the northern region, especially when there is less rainfall in winter, it is difficult to realize rainwater reuse. Secondly, the small water body in this invention is not suitable for general application in the renovation of existing communities, because it freezes and dries up in winter, and the landscape effect is poor; Thirdly, the reuse system of this invention is self-contained, and it is not combined with the landscape layout of the existing community, nor does it consider how to skillfully integrate with the levels of the green space in front of and behind the house, the group green space, and the community green space. Finally, this invention lacks the design of the combination with the traffic system of the community, especially for the rainwater treatment of roads and parking areas with serious rainwater pollution in the community.

The structure disclosed by the Chinese patent titled "Residence Group Rainwater Ecological Drainage System" includes: 1 multiple downpipes; 2 multiple rain-collecting bottles with an initial rainwater abandonment system, and multiple rain-collecting bottles are respectively arranged on each The bottom of the downpipe; 3. Multiple concave green spaces in front of and behind the house set between the residence and the group road. The multiple concave green spaces in front of and behind the house respectively communicate with the corresponding rain-collecting bottles through the overflow on the rain-collecting bottles. The pipes are connected; 4 concave group central green spaces, there are multiple water troughs on the roads of the group, and the multi-block green spaces in front of and behind the house are respectively connected to the central green space of the concave group through corresponding water troughs; the concave group green space A shallow vegetation ditch parallel to the direction of the residence is set in the central part; 5 groups of rain gardens are set up on the lowest elevation side of the shallow vegetation ditch.

The invention patent mainly focuses on the relatively small residential groups, forming an independent and complete system composed of rainwater bottles, concave green spaces and rain gardens, which is only a single-stage system. The invention patent only focuses on the rainwater infiltration and utilization system in the residential group green space; the invention patent does not emphasize the strategy for the characteristics of the existing residential areas in the north; the invention patent emphasizes the multi-objectives of rainwater reuse from rainwater bottles and infiltration of recessed green spaces and rain gardens Stormwater Design Strategies.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art, and provide a method of using rainwater as a "resource" for on-site infiltration, thereby reducing the amount of rainfall, storing stagnation, and delaying the peak of rain, so as to achieve the purpose of sponge city to alleviate urban waterlogging disasters The tandem multi-level rain garden infiltration system of the existing community.

The present invention's continuous multi-stage rainwater garden infiltration system in existing residential quarters comprises:

(a) a plurality of roof gardens, the plurality of roof gardens are arranged on the flat roofs of existing residential quarters;

(b) a plurality of downpipes, the plurality of downpipes are respectively connected to the rainwater system of the roof garden on the flat roof of the residence, so that the rainwater can flow into the downpipe through the roof garden rainwater system;

(c) A plurality of first-level rain gardens, the plurality of first-level rain gardens are respectively arranged at the bottom of each downpipe and between the residence and the group road, and the plurality of first-level rain gardens Located in the green space in front of the house and behind the house, the rainwater collected by the roof garden of the residence directly enters the first-level rain garden through the downpipe; The elevation of the green space in front of the house and behind the house is lower than that of the group road;

(d) Multiple blocks of low-potential group central greenbelts, the elevation of the multiple low-potential group central greenbelts is lower than the group road, and the described group roads are set on both sides of the low-potential group central greenbelt. Set a shallow vegetation ditch parallel to the direction of the residence in the central part of the central green space of the potential group, and set a shallow vegetation ditch in the parking area in each concentrated parking area. The elevation of the shallow vegetation ditch in the parking area gradually decreases from the center of the plot to the edge of the plot;

(e) a plurality of second-level rain gardens, the plurality of second-level rain gardens are set at the end of the shallow vegetation ditch; in the residential group of residents' activities, the first-level rain gardens are connected to each other through corresponding overflow pipes The vegetation shallow ditch is connected or directly connected with the second-level rain garden, so that the excess rainwater accumulated in the first-level rain garden can enter the vegetation shallow ditch or the second-level rain garden through the overflow pipe, and the second-level rain garden in turn The corresponding overflow pipe and vegetation shallow ditch are connected to the third-level rain garden in the low-lying green space in the center of the community, so that the rainwater from the second-level rain garden can be concentrated to the third-level rain garden, and the third-level rainwater The exit of the garden is connected to the rainwater pipeline of the residential area through the overflow pipe; in the parking area where the parking spaces are concentrated, the vegetation shallow ditch in the parking area is directly connected to the second-level rainwater garden in the parking area. The first-level rainwater garden is connected with the rainwater pipeline set under the roadway outside the community through the overflow pipe, so that the rainwater in the parking area is concentrated from the second-level rainwater garden in the parking area to the rainwater pipeline set up under the roadway outside the community. The above-mentioned overflow pipe is laid at the bottom of the group road;

The first-level rain garden, the second-level rain garden and the third-level rain garden are composed of planting vegetation, covering layer, planting soil layer, infiltration layer, sand filter layer and gravel cushion from top to bottom. The elevation of the first-level rain garden is higher than the elevation of the second-level rain garden, and the elevation of the second-level rain garden is higher than the elevation of the third-level rain garden; the elevation of the water inlet of the overflow pipe is low On the surrounding roads and 15-25cm higher than the covering layer of the rain garden, the elevation of the outlet of the overflow pipe is higher than the vegetation covering layer and lower than the water inlet elevation of another overflow pipe of the rain garden.

Advantages of the present invention:

1 Focus on restoring rainwater infiltration and utilization

The rainwater is infiltrated into the ground in situ through infiltration facilities such as multi-level rainwater gardens, low-lying green spaces, and shallow vegetation trenches, so as to achieve:

——Groundwater resources are supplemented, and the abundant groundwater can be drawn by residents for production and life, avoiding long-distance water transfer, indirectly alleviating the shortage of water resources and reducing ground subsidence;

——Rainwater seeps into the ground, reducing surface runoff, thereby alleviating the problem of flood disasters;

——The soil plays a purifying function during the infiltration of rainwater; the low-lying green space, shallow vegetation ditch, and rain garden all purify the rainwater runoff. These purification functions can reduce pollution problems in surface water systems.

2 Increase rainwater storage space

Through the water storage space of the roof garden, the water storage space of the shallow vegetation ditch, and the water storage space of the rain garden, the rainwater is stored on the spot, so as to achieve:

——Delayed discharge and staggered peak of rain and flood peaks to alleviate the problem of waterlogging disasters;

——Increase water supply for landscape plants in residential quarters.

3 Delay runoff peak time

The rainwater in the upper rain garden will overflow to the lower rain garden after it is full. Therefore, through the step-by-step overflow method of the multi-level rain garden system, combined with the rainwater flow of low-lying green land and shallow vegetation ditch, it makes While the rainwater runoff is continuously reduced, the peak time of runoff is continuously delayed. This delay is helpful for the mitigation of urban waterlogging disasters.

4 This system combines rainwater drainage with landscape greening at all levels of the community

Compared with the current design generally used in the design, the planner first conducts the overall layout planning, and then the landscape architect conducts the environmental design of the general plane landscape greening, environmental sketches, leisure facilities, etc., and finally the engineer conducts the "supporting" of the rainwater infrastructure pipeline. The design method is different. This multi-level rain garden system can be consistent with the landscape greening system of the green space in front of the house, the group green space, and the community green space. It combines the environmental landscape greening layout with the rainwater ecological infiltration and storage. Rainwater ecological discharge.

5 Reduce investment in storm water pipes

The "'continuous' multi-stage rainwater garden infiltration system in the existing community" constructed by the present invention realizes the reduction of rainfall and the delay of rain peak through infiltration and stagnation, which can reduce the investment in increasing the diameter of rainwater pipelines. In the reconstruction of existing communities, the existing rainwater pipelines in the existing communities can be retained, and the design requirements for a higher return period can be met through landscape transformation, so as to achieve the goal of sponge city construction.

6 Applicable to the renovation of existing residential areas

The "'serial type' multi-stage rainwater garden infiltration system in existing residential quarters" constructed by the present invention can transform flat roofs into roof gardens and green turf into The measures of transforming low-lying green space and local green space into multi-level rain gardens realize the on-site infiltration of rainwater in existing residential areas. This mode can be synchronized with the greening and landscape renovation of the community, which not only beautifies the landscape of the community, but also achieves the purpose of reducing surface runoff of rainwater, and at the same time does not make large-scale changes to the buildings.

7. Integrating rainwater quality infiltration or discharge into traffic transformation of people-vehicle diversion

Through the landscape transformation of the existing community, the design of the separation of pedestrians and vehicles is realized, and the rainwater polluted by vehicles is discharged into the peripheral rainwater pipeline system of the community after preliminary soil purification through shallow vegetation ditch and rain garden; the pedestrian system with less pollution passes through The multi-level rain garden is organized into the central rain garden of the community to infiltrate and replenish groundwater. Therefore, the infiltration or discharge of rainwater is achieved through the separation of people and vehicles.

8 Applicable to areas with less rainfall in the north

Vegetation shallow ditches, low-lying green spaces, and rain gardens all have the effect of greening the landscape. While meeting the landscape effect of the community, they are also suitable for rainwater infiltration in the case of less rainfall in the north. Its limited stagnation space is slightly insufficient in the Jiangnan area with more rainfall.

9 This system mainly focuses on larger residential quarters, emphasizing the progressive composition of the multi-level rain garden system "serial" and emphasizing the source control concept of infiltrating and decreasing rainwater from the roof of the source to the multi-level rain garden; this system Focus on the stormwater management strategy of the overall layout of the community, emphasizing the infiltration and purification of car-polluted rainwater through the rain garden through the traffic organization, and then discharge it into the pipeline outside the community, emphasizing the infiltration of unpolluted rainwater in the human activity area to the multi-level rain garden at the core of the internal landscape of the community; This system is mainly aimed at the northern multi-storey existing communities with low rainfall and many flat roofs. These existing communities lack traffic organization, parking everywhere, high hardening rate, and large rainwater runoff. The flat roofs are transformed into roof greening and landscape greening into multi-level The rain garden system and traffic parking are transformed into independent systems and the rainwater is purified and infiltrated before being discharged, so as to realize the infiltration and utilization of rainwater in the existing residential areas in the north. This system focuses on the low-cost infiltration and utilization of existing communities from source roof gardens, concave green spaces, shallow vegetation trenches and multi-level rainwater gardens.

Description of drawings

Fig. 1 is the plane layout diagram of the multi-level rain garden infiltration system of the existing residential quarter of the serial type of the present invention;

Fig. 2 is the A-A longitudinal sectional view of the infiltration system shown in Fig. 1;

Fig. 3 is the B-B transverse sectional view of the infiltration system shown in Fig. 1;

Fig. 4 is a C-C longitudinal sectional view of the overflow pipe in the permeation system shown in Fig. 1 .

detailed description

As shown in the accompanying drawings, the present invention's tandem multi-stage rainwater garden infiltration system in the existing residential area comprises:

(a) a plurality of roof gardens 1, the plurality of roof gardens are arranged on the flat roofs of existing residential quarters.

(b) a plurality of downpipes 2, the plurality of downpipes are respectively connected to the rainwater system of the roof garden on the flat roof of the house, so that the rainwater can flow into the downpipe through the rainwater system of the roof garden;

(c) a plurality of first-level rain gardens 3, the plurality of first-level rain gardens are respectively arranged at the bottom of each downpipe 2 and arranged between the residence and the group road, the first-level rain gardens 3 is located in the green space 4 in front of the house and behind the house, and the rainwater collected by the residential roof garden 1 directly enters the first-level rain garden 3 through the downpipe 2; the elevation of the outer edge of the first-level rain garden 3 is lower than that in front of the low-rise house The green land 4 behind the house is so that the rainwater that cannot be accommodated by the green land 4 in front of the house and the back of the house is infiltrated into the first-level rain garden 3, and the green land 4 behind the house in front of the low power house is lower than the group road in elevation;

(d) a plurality of low-potential group central green spaces 6, the elevation of the multi-block low-potential group central green spaces is lower than the group roads, and the described group roads are set on both sides of the low-potential group central green spaces. A vegetation shallow ditch 7 is set parallel to the direction of the residence in the central part of the central green space of the low-potential group, and a vegetation shallow ditch 7 in the parking area is set in each concentrated parking area. The elevation of the vegetation shallow ditch 7 is from the edge of the community to the central side of the community Gradually decrease, the elevation of the shallow vegetation ditch in the concentrated parking area gradually decreases from the center side of the plot to the edge side of the plot;

(e) A plurality of second-level rain gardens 8, the plurality of second-level rain gardens 8 are arranged at the end of shallow vegetation ditch; in the residential group of residents' activities, the first-level rain gardens 3 respectively pass through the overflow pipe 5 It is connected with the vegetation shallow ditch 7 or directly connected with the second-level rain garden 8 so that the excess rainwater accumulated in the first-level rain garden 3 is input into the vegetation shallow ditch 7 or the second-level rain garden 8 through the overflow pipe 5, The second-level rain garden 8 is connected to the third-level rain garden 10 in the central low-lying green space 9 of the community through the overflow pipe 5 and the vegetation shallow ditch 7 in turn, so that the second-level rain garden rainwater flows to the third-level rain garden 10 Centralized, the outlet of the third-level rain garden 10 communicates with the rainwater pipeline of the community through the overflow pipe; 8 are directly connected, and the second-level rainwater garden 8 of the parking area is connected to the rainwater pipeline provided under the peripheral roadway of the community through an overflow pipe, so that the rainwater in the parking area can flow from the second-level rainwater garden 8 of the parking area. Concentrate to the rainwater pipeline that is set under the roadway outside the community, and the overflow pipe 5 is laid at the bottom of the group road;

The first-level rain garden 3, the second-level rain garden 8 and the third-level rain garden 10 are composed of planting vegetation, covering layer, planting soil layer, infiltration layer, sand filter layer and gravel cushion from top to bottom , the elevation of the first-level rain garden 3 is higher than the elevation of the second-level rain garden 8 , and the elevation of the second-level rain garden 8 is higher than the elevation of the third-level rain garden 10 .

The elevation of the water inlet 11 of the overflow pipe 5 is lower than the surrounding roads and higher than the covering layer of the rain garden by 15-25 cm, so that the accumulated water in the rain garden is always at a reasonable level, preventing excessive rainwater from affecting the rain garden. Plant growth causes adverse effects, and the elevation of the outlet 12 of the overflow pipe 5 is higher than the vegetation cover and lower than the water inlet elevation of another overflow pipe in the rain garden. Therefore, the water inlet 11 can control the water storage depth of the rain garden, and transport excessive rainwater to the outlet 12 in the next rain garden through the overflow pipe 5 . Generally, the three-stage rain garden can store 25 cm deep rainwater through the water inlet 11 . In order to prevent plant leaves and sundries from blocking the water inlet 11 and the outlet 12, preferably a grid grate is set at the water inlet 11 and the outlet 12 of the overflow pipe 5 and the surface covering is cleaned regularly.

As shown in Figure 4, the elevation of the overflow pipe inlet = the elevation of the rain garden + the storage height, the elevation of the overflow pipe inlet of the upper rain garden is higher than the outlet elevation of the lower rain garden, and the overflow pipe outlet Set it in an inverted "U" shape to reduce plant leaves and sundries.

Preferably, according to the local rainfall conditions, perforated pipes for collecting water are embedded in the gravel cushions of the first, second and third rain gardens, and the first, second and third rainwater Reservoirs are respectively arranged underground around the garden, and the perforated pipes for collecting water are connected to the reservoirs, and the purified rainwater is collected and transported to the reservoirs by the perforated pipes for collecting rainwater, and the rainwater is stored for reuse. The reservoir is provided with a water supply pump and an inspection port, the inspection port is used for sludge and sediment cleaning, and the water supply pump can extract the collected rainwater for various reuse purposes.

The low-level green space of this system is a green space whose index height is lower than that of surrounding roads or square pavement, which has the advantages of purifying rainwater runoff and improving the effect of rainwater storage and infiltration. Its elevation setting can ensure that the rainwater from the surrounding confluence surface flows into the low-lying green space, and the excess rainwater is discharged through the overflow of the rain garden. In addition, in order to improve the infiltration capacity, infiltration facilities can also be installed.

Vegetation shallow ditch is an engineering measure to collect and treat runoff rainwater through gravity flow after vegetative treatment of surface ditches, which can achieve the functions of collecting and transporting rainwater runoff, reducing flood peaks and purifying runoff pollution. Its cross-sectional design often adopts three forms: trapezoidal, parabolic and triangular.

Rain garden, its English name is Rain Garden, also known as bioretention pond, bioretention pond or bioretention tank, generally consists of pretreatment grass ditch, planting vegetation, water storage area, covering layer, planting soil layer, infiltration layer, Composed of sand filter layer, gravel cushion, drainage system and overflow device, it is one of the most commonly used and most important methods in LID development models such as urban rainwater runoff control and non-point source pollution control.

The present invention has realized five-step osmotic storage stagnation, specifically as follows:

1 On the flat roof of the existing residence, a roof garden or a roof family vegetable garden is set up according to local conditions, so as to realize the first step of infiltration and stagnation of rainwater. The rainwater is then funneled through the roof rainwater system into the downpipes.

2. Set the first-level rain garden at the bottom of the downpipe. The rainwater in the low-lying green land where the first-level rain garden is located realizes the infiltration of rainwater on the spot. Excessive rainwater enters the first-level rain garden, thereby realizing the second step of infiltration and storage of rainwater lag.

The central green space of the 3 groups also adopts the method of low-level green space, and the elevation is lower than the roads of the surrounding groups. The central position of the group green space is parallel to the building and a shallow vegetation ditch is set up to catch water from the periphery of the group to the center. Ground infiltration is the third step of infiltration and stagnation of rainwater.

4 Plan to set up a second-level rain garden at the lowest point of the green space in the group center. The excess rainwater in the first-level rain garden overflows through the overflow pipe to the vegetation shallow ditch in the green space in the group center or the second-level rain garden, and the rainwater of the entire residential group passes through The surplus rainwater intercepted and infiltrated by various facilities will finally flow to the second-level rain garden, realizing the fourth step of infiltration and stagnation of residential group rainwater.

5 Similarly, in the green space in the center of the community, the method of low-level green space is also used to collect water from the periphery to the center. The excessive rainwater in the second-level rain garden is poured into the shallow vegetation ditch or the third-level rain garden through the overflow pipe, and the third-level rain garden It is the core facility for rainwater infiltration in residential quarters, realizing the fifth step of infiltration and stagnation of rainwater in residential quarters.

Claims (4)

1. The multi-stage rain garden infiltration system of the existing residential area in series, is characterized in that it includes: (a) a plurality of roof gardens (1), the plurality of roof gardens are arranged on the flat roofs of existing residential quarters; (b) a plurality of downpipes (2), the plurality of downpipes are respectively connected to the rainwater system of the roof garden on the flat roof of the residence, so that the rainwater can flow into the downpipe through the roof garden rainwater system; (c) a plurality of first-level rain gardens (3), the plurality of first-level rain gardens are respectively arranged at the bottom of each downpipe (2) and arranged between the residence and the group road, and the plurality of A first-level rainwater garden (3) is located in the green land (4) behind the house in front of the house, and the rainwater collected by the residential roof garden (1) directly enters the first-level rainwater garden (3) through the downpipe (2); The elevation of the outer edge of the first-level rain garden (3) is lower than the green space (4) in front of the low-potential house and behind the house, and the elevation of the green space (4) behind the low-potential house in front of the house is lower than the group road; (d) a plurality of low-potential group central greenbelts (6), the elevation of the multiple low-potential group central greenbelts is lower than the group roads, and the described group roads are set on both sides of the low-potential group central greenbelts. A vegetation shallow ditch (7) is set parallel to the residential direction in the central part of the central green space of the low-potential group, and a vegetation shallow ditch (7) in a parking area is set in each concentrated parking area, and the elevation of the vegetation shallow ditch (7) It gradually decreases from the edge of the community to the center of the community, and the elevation of the shallow vegetation ditch in the concentrated parking area gradually decreases from the center of the community to the edge of the community; (e) a plurality of second-level rain gardens (8), the plurality of second-level rain gardens (8) are set at the end of shallow vegetation ditch; in the residential group of residents' activities, the first-level rain gardens (3) The corresponding overflow pipes (5) are respectively connected to the vegetation shallow ditch (7) or directly connected to the second-level rain garden (8) to allow excess rainwater accumulated in the first-level rain garden (3) to pass through The overflow pipe (5) enters the vegetation shallow ditch (7) or the second-level rain garden (8), and the second-level rain garden (8) passes through the corresponding overflow pipe (5) and the vegetation shallow ditch (7) and The third-level rain garden (10) in the central low-lying green space (9) of the community is connected, so that the rainwater of the second-level rain garden is concentrated to the third-level rain garden (10), and the third-level rain garden (10) ) is connected to the residential rainwater pipeline through the overflow pipe; in the parking area where the parking spaces are concentrated, the vegetation shallow ditch (7) in the parking area is directly connected with the second-level rainwater garden (8) in the parking area, and the The second-level rainwater garden (8) in the parking area is connected to the rainwater pipeline installed under the roadway outside the community through the overflow pipe, so that the rainwater in the parking area flows from the second-level rainwater garden (8) in the parking area to the community. The rainwater pipelines arranged under the peripheral roadway are concentrated, and the overflow pipe (5) is laid at the bottom of the group road; The first-level rain garden (3), the second-level rain garden (8) and the third-level rain garden (10) are composed of planting vegetation, covering layer, planting soil layer, infiltration layer, and sand filter from top to bottom. layer and a gravel cushion, the elevation of the first-level rain garden (3) is higher than that of the second-level rain garden (8), and the elevation of the second-level rain garden (8) is higher than that of the third The elevation of the level rain garden (10); the elevation of the water inlet (11) of the overflow pipe (5) is lower than the surrounding road and higher than the rain garden covering layer of 15-25cm, and the overflow pipe ( 5) The elevation of the outlet (12) is higher than the vegetation cover and lower than the elevation of the water inlet of another overflow pipe in the rain garden. 2. The multi-stage rainwater garden infiltration system of the tandem existing residential area according to claim 1, characterized in that: the water inlet (11) and the outlet (12) of the overflow pipe (5) are provided with Grid grate. 3. The continuous multi-stage rainwater garden infiltration system for existing residential quarters according to claim 1 or 2, characterized in that: the outlet of the overflow pipe is set in an inverted "U" shape. 4. According to claim 1 or 2, the multi-stage rainwater garden infiltration system of the serial type existing residential area is characterized in that: it is embedded in the gravel cushions of the first, second and third rain gardens There are water-collecting perforated pipes, and reservoirs are respectively arranged underground around the first-level, second-level, and third-level rain gardens. The water-collecting perforated pipes are connected with the reservoirs, and the purified rainwater is collected from the water The perforated pipe is collected and transported to the water storage tank, and the water storage tank is provided with a water supply pump and a maintenance port.