U.S. patent application number 15/443811 was filed with the patent office on 2017-06-15 for passive capillary and gravity drainage system and method.
This patent application is currently assigned to SUBAIR SYSTEMS LLC. The applicant listed for this patent is SUBAIR SYSTEMS LLC. Invention is credited to Chris des Garennes, Peter van Drumpt.
Application Number | 20170167098 15/443811 |
Document ID | / |
Family ID | 46671150 |
Filed Date | 2017-06-15 |
United States Patent
Application |
20170167098 |
Kind Code |
A1 |
des Garennes; Chris ; et
al. |
June 15, 2017 |
PASSIVE CAPILLARY AND GRAVITY DRAINAGE SYSTEM AND METHOD
Abstract
A system for draining liquid from soil is disclosed. The system
includes a passive capillary drain in combination with a core for
gravity flow, including a sand top dressing layer, a native soil
interface, and a rootzone, a curtain traversing from the sand
topdressing layer through the native soil interface to at least one
tube element, the at least one tube element pulling the water out
of the soil with capillary suction, and a core central to the at
least one tube element that moves excess water via gravity flow
with capillary suction. The elements may be installed parallel at a
3 feet center and a depth of 10 inches, and/or may be installed
vertically.
Inventors: |
des Garennes; Chris;
(Elkton, MD) ; van Drumpt; Peter; (Wilmington,
NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SUBAIR SYSTEMS LLC |
Graniteville |
SC |
US |
|
|
Assignee: |
SUBAIR SYSTEMS LLC
Graniteville
SC
|
Family ID: |
46671150 |
Appl. No.: |
15/443811 |
Filed: |
February 27, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13399708 |
Feb 17, 2012 |
|
|
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15443811 |
|
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61444310 |
Feb 18, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E02B 11/00 20130101;
E02B 11/005 20130101 |
International
Class: |
E02B 11/00 20060101
E02B011/00 |
Claims
1. A method of installing a system for draining liquid from a soil
surface, the method comprising: installing a plurality of tube
elements each including a central core approximately one foot below
the surface, wherein adjacent ones of the plurality of tube
elements are substantially parallel to other ones of the plurality
of tube element, the installed plurality of tube elements draining
liquid using capillary suction and gravity flow; creating a sand
curtain extending from just under the surface to the top of the
plurality of tube elements to eliminate a capillary break of the
soil by providing a continuous pathway of capillary pores to drain
liquid from the soil surface to the plurality of tube elements; and
installing a drain with a drop to incorporate a hanging water
column to provide for increased capillary suction of the plurality
of tube element to enhance the draining of the liquid from the
soil.
2. The method of claim 1, wherein creating of the sand curtain
comprises a vibratory plow.
3. The method of claim 1, wherein just under the surface is
approximately two inches below the surface.
4. The method of claim 1, wherein the sand curtain created is
approximately one-half inch long.
5. The method of claim 1, wherein the plurality of tube elements
are installed from 8 to 16 inches below the surface.
6. The method of claim 1, wherein the plurality of tube elements is
spaced using an approximate three-foot spacing between adjacent
tube elements.
7. The method of claim 1, wherein the drop is in a range of
approximately 1 to 10 inches.
8. The method of claim 1, wherein the drop is in a range of
approximately 4 to 8 inches.
9. The method of claim 1, wherein the drop is approximately 6
inches.
10. The method of claim 1, wherein the sand curtain is less than
approximately one inch in diameter.
11. The method of claim 1, wherein the sand curtain is less than
approximately 3/8 inches in diameter.
12. The method of claim 1, wherein the core comprises a stainless
steel mesh.
13. The method of claim 1, wherein the plurality of tube elements
comprise fiberglass elements.
14. The method of claim 1, wherein the sand curtain comprises
another of the plurality of tube elements include a rigid core.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 13/399,708 filed on Feb. 17, 2012, which
claims the benefit of U.S. Provisional Application No. 61/444,310,
filed Feb. 18, 2011, which is incorporated by reference as if fully
set forth.
FIELD OF INVENTION
[0002] The instant disclosure relates to drainage systems and
methods, and, more particularly, to a passive capillary and gravity
drainage system and method.
BACKGROUND
[0003] Turf grass areas, such as those on golf courses, are
typically subject to moderate to heavy foot traffic on a daily or
weekly basis. Excessive water retention in such areas is highly
undesirable due to the damage that may occur as a result of foot
traffic and other factors. Thus, turf grass areas are reconstructed
to include some drainage capability. The soil profile of such areas
is commonly constructed as an excavation into the soil native to
the site. A high sand content root zone and frequently coarse sand
or fine gravel sub-layers are subsequently placed within this
excavation. Subsurface drainage from this essentially closed basin
is necessary and is typically provided by drainage pipe spaced from
three (3) to six (6) meters apart and placed in shallow trenches in
the sub-grade soil. One example of such a turf soil profile is that
used in putting greens by the United States Golf Association
("USGA").
[0004] Depending on the availability of suitable root zone and
gravel materials, a putting green soil profile typically consists
of a 300 mm thick, high sand content root zone mix positioned above
a minimally 100 mm thick, predominately fine gravel zone. The
gravel rests on the sub-grade soil except when adjacent to drain
line trenches, where the same gravel also fills the trench. The
particle size distribution of the gravel typically conforms to
engineering specifications for a drainage filter. Such conformity
helps to ensure maintenance of layer integrity and suitable
hydraulic performance of the gravel.
[0005] During and shortly after rainfall, the gravel layer of, for
example, a USGA putting green, promotes rapid drainage of the root
zone. Excess water exiting the root zone follows a nearly vertical
path, employing the maximum extent of the gravitational gradient.
The maximal distance drainage water must travel to exit the root
zone is virtually the root zone depth, or approximately 300 mm.
Lateral flow to the spaced apart drainage elements occurs mostly
within the very high permeability gravel layer. The gravel drainage
blanket beneath the finer textured root zone also creates a large
difference in the pore size distribution across this interface.
This large separation of predominate pore sizes within these
adjacent media yields a capillary break in the vertical direction.
Consequently, the lower portions of the root zone remain saturated
(or nearly so) after drainage has virtually ceased. Depending on
the particle sizes of the root zone and gravel materials used for a
given installation, the thickness of this perched water zone may
vary. For coarser root zone and finer gravel textures, a thinner
perched water zone will form and the upper surface of the capillary
fringe will still reside at sufficient depth to ensure adequate
air-filled porosity near the soil surface. For finer root zone and
coarser gravel textures, the perched water zone will be quite thick
and may severely reduce the proportion of air-filled pores near the
soil surface.
[0006] Surface slopes, such as those found on putting greens and
athletic fields, also occur on or at the interfaces between soil
layers within the profile. This is because profile layers are
typically built to a uniform thickness across the green or field.
When the interface between layers is well defined, and there is a
wide disparity between soil textures of adjacent layers, the
accumulation of water is subject to interflow. This down-slope
movement of subsurface water is particularly evident in profiles
with high permeability root zone media and greater root zone
depths. Presumably, only a high permeability root zone would allow
sufficient rates of interflow for the modest slopes of these
systems. A deeper profile depth may provide a greater reservoir of
soil water available for such flow. Consequently, the excess and
perched water of a USGA green would in time migrate down slope
resulting in lower soil water contents at higher elevation
locations and higher water contents at lower elevation locations
across the field or green.
[0007] This phenomena results in the need for localized hand
watering of high elevation locations within some putting greens, a
costly and time consuming operation. Thus, it is evident that a
high sand content root zone placed over a gravel layer provides
rapid drainage during and shortly after a rainstorm. However, after
this rapid drainage phase has ended, excess and perched water that
is retained in the root zone results in localized soil wetness and
laterally non-uniform soil water content across naturally contoured
putting greens and athletic fields.
[0008] The prior art includes technologies designed to address the
excess and perched water problem. Commercial applications typically
consist of using air pumps or blowers to apply a sub-atmospheric
pressure within the gravel layer. The vacuum thus helps remove the
excess and perched water. This, however, is an active process
requiring motor driven blowers and functions only during such times
that the vacuum is applied. Thus, there is a need for a system that
effectively removes excess and perched water using existing drains,
but that is passive, that is, requires no human or mechanical
intervention, and that continues to function as long as excess
water is present in the soil profile.
[0009] Therefore, there is a need for a passive capillary system in
combination with a gravity system that effectively removes excess
and perched water, in sufficient volumes, while using no energy,
requires no human or mechanical intervention and that continues to
function as long as excess water is present in the soil.
SUMMARY
[0010] A system for draining liquid from a layered soil profile is
disclosed. The system includes a passive capillary and gravity
drain including a sand topdressing layer, a native soil interface,
and a rootzone, a curtain traversing from the sand top dressing
layer through the native soil interface to the at least one tube
element that passively collects the fluid proximate to the at least
one tube element, the at least one tube element draining the fluid
from the layered soil profile, and a core central to the at least
one tube element that collects and moves the excess water with
gravity flow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Understanding of the present invention will be facilitated
by consideration of the following detailed description of the
preferred embodiments of the present invention taken in conjunction
with the accompanying drawings, in which like numerals refer to
like parts:
[0012] FIG. 1 illustrates the passive capillary and gravity
drainage system of the present invention;
[0013] FIG. 2 illustrates the core and the at least one tube
element of the present invention;
[0014] FIG. 3, illustrates a layout of the present system according
to an aspect of the present invention;
[0015] FIG. 4 illustrates a comparison of the present system to a
conventional drainage system; and
[0016] FIG. 5 illustrates a method of drainage according to an
aspect of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] It is to be understood that the figures and descriptions of
the present invention have been simplified to illustrate elements
that are relevant for a clear understanding of the present
invention, while eliminating, for the purpose of clarity, many
other elements found in soil and drainage systems. Those of
ordinary skill in the art may recognize that other elements and/or
steps are desirable and/or required in implementing the present
invention. However, because such elements and steps are well known
in the art, and because they do not facilitate a better
understanding of the present invention, a discussion of such
elements and steps is not provided herein. The disclosure herein is
directed to all such variations and modifications to such elements
and methods known to those skilled in the art.
[0018] The present system and method enables the drainage of
surface water faster by placing the elements closer than
conventional sand channel systems, such as at half the distance,
for example. The elements of the present system provide fast
free-gravity flow through a core, plus capillary suction through
the surrounding parts of the element. For example, the elements of
the present system may be placed 3 feet apart and 8 to 16 inches
below the surface, and used a sand curtain to draw trapped surface
water to the elements for fast, effective drainage.
[0019] Layering is common in putting green soils, and occurs when a
sandy root zone overlays a finer textured native soil, which is
typical after years of top dressing. In these push-up greens the
interface is often too close to the surface, resulting in wet soil
problems for the turf. For example in USGA greens, excess water
tends to perch where the sandy root zone interfaces with the gravel
layer. This perched water is held at a slight suction, so it is
unable to enter conventional draining systems. The present solution
is a drainage system that works two ways. The first way is that the
elements are placed at the bottom of the narrow sand curtain, which
gives water trapped at the soil interface an exit. The unique
element has an open stainless steel mesh core to remove large
amounts of water quickly through gravitational flow. The second way
is the element is made of highly conductive fiber glass, in which
the spaces between the fibers match the pore sizes of the sandy
root zone. The result of the present invention utilizing these
aspects is a system that drains fast with passive capillary and
gravity drainage and wicks away excess soil moisture with capillary
suction 24 hours a day without the use of active means such as
motors, pumps or other energy input. A hanging water column may be
created at the outlet by incorporating a gravity drop. This hanging
water column may provide for further capillary suction. Any size
drop may provide a hanging water column, but a drop in the range of
1 inch to 10 inches may provide the appropriate capillary suction.
More specifically, a drop of approximately 4-8 inches, or even more
specifically approximately 6 inch drop may provide the appropriate
hanging water column. The present system creates an effective
suction effect that follows the natural contours of the surface, is
installed only where drainage problems exist, and helps improve
turf health by providing better drainage to chronically wet
soils.
[0020] Referring now to FIG. 1, there is shown a depiction of the
passive capillary and gravity drainage system 100 of the present
invention. The passive capillary and gravity drainage system 100
may include a sand topdressing layer 110, a native soil interface
120, a drain 130, at least one tube element 140, and a core
150.
[0021] Sand topdressing layer 110 may be located adjacent to, and
usually above, native soil interface 120. This boundary with native
soil interface 120 may cause water to be captured and prevented
from draining. Rootzone may be included within the native soil
interface 120. Drain 130 may include a curtain that traverses from
sand top dressing layer 110 through the native soil interface 120
to at least one tube element 140 and core 150. At least one tube
element 140 may utilize capillary suction to collect fluid
proximate to at least one tube element 140 and thereby drain this
fluid from the layered soil profile. Core 150 moves collected
fluid, such as by using gravity, from at least one tube element 140
and drains 130 to remove fluid from the layered soil profile.
[0022] Sand topdressing layer 110 may arise from practice of
topdressing soil, including golf greens, as described herein. This
practice has also been extended to fairways, sports fields and
other prepared soil landscaping areas. Sand topdressing layer 110
may cause layering which occurs when a discrete layer of sand or
thatch is formed over the rootzone, as discussed. This discrete
layer may act as an impediment to the movement of water and oxygen.
Sand topdressing layer 110 may include sand that is compatible with
the existing rootzone material. Topdress/rootzone compatibility may
be determined by performing a particle size analysis on the
existing rootzone material and the proposed topdress.
[0023] Topdressing is the process of adding a fine layer of quality
soil to the surface. Topdressing benefits the lawn as it builds up
the quality of the soil over a period of time. By adding
topdressing, sandy soils may be able to retain moisture to allow
the lawn to be more resistant to drought, and clay soils may drain
better to thereby improve root development. Another benefit of top
dressing may be to help even out any lumps and bumps that are
present on an uneven lawn, green, or field by filling in any small
hollows that may have developed. Top dressing may also stimulate
the grass to produce new shoots and thereby may result in denser
grass cover which helps combat the onset of weed and moss
infestation.
[0024] Native soil interface 120 may include the interface that has
been dressed with the top dressing. Native soil interface 120 may
be created without the presence of a sand topdressing layer 110.
Native soil interface 120 may occur at any barrier to the transfer
of materials including water, for example. Native soil interface
120 may create a barrier for the transfer of materials, such as
nutrients and water, between layers. Water, nutrients and roots
have distaste for passing between dissimilar levels. The present
invention provides a system that penetrates, or pierces, this
native soil interface 120 in order to allow moisture and water to
drain therefrom.
[0025] Drain 130 may be formed using a narrow sand curtain, for
example. Drain 130 may be a portion of a drainage system 100 that
includes a multitude of drains separated apart by 3 feet. Such a
drain 130 may include a 3/8 inch sand curtain spaced apart at 3
feet spacing, for example. Drain 130 may be installed within a
layered, turf soil profile. Drain 130 may be oriented vertically
and span from the sub-grade soil surface to about 100 mm into the
lower portions of the root zone exiting into existing gravel or
parallel passive capillary lines. That is, drain 130 may provide a
path from the perched fluid to at least one tube element 140 and
core 150. Drain 130 may take the form of a sand curtain with a
dimension of approximately 3/8 inches. Drain 130 may provide a
continuous pathway of capillary pores from the lower reaches of the
root zone and through the gravel layer, thus eliminating the
capillary break present in layered soils created by the top
dress/native soil interface 120. Drain 130 may have a small
diameter (c.a. <1 inch) so that installation will minimally
disrupt the existing root and environment. In an exemplary
embodiment, drains 130 are spaced apart (c.a. 3 feet) as to not
inhibit the lateral flow characteristics of the gravel layer.
Furthermore, drain 130 may maintain physical integrity within the
gravel layer when lateral flow conditions exist. Finally, drain 130
may have a sufficient flow capacity to allow timely removal of the
excess and perched water. This flow capacity may be based on
particle size and a comparison of the particle size to the
surrounding sections, such as the top dress and rootzone, for
example.
[0026] To effectively and efficiently remove perched water in a
layered profile, a passive capillary drain of the present invention
typically includes a distribution of pore sizes and compatibility
with the root zone to provide a continuous pore pathway spanning
the gravel layer. If the majority of pores in capillary drain 130
are substantially larger than the rootzone, a capillary break may
occur at the interface between the capillary drain 130 and roots,
thereby disrupting the pathway. However, if the pores of drain 130
are substantially smaller than the root zone, drain 130 would have
insufficient hydraulic conductivity to convey flow in a predictable
and efficient fashion.
[0027] At least one tube element 140 may be designed to draw and
capture water through capillary or other physical actions when
excess water is present and/or water is perched adjacent to, above,
or below element 140. Another aspect of at least one tube element
140 is that fines do not clog the pores due to the relatively slow
water velocity under the surface.
[0028] In an exemplary embodiment, fiberglass rope may be utilized
for constructing at least one tube element 140 of the present
invention. The water retention and hydraulic conductivity
properties of some commercially available fiberglass ropes, as well
as the use of fiberglass as a passive capillary sampler of soil, is
known in the art. Ropes ranging in diameter from about 0.25 to 1
inch (0.64 to 2.54 cm) have been shown in the scientific literature
to have water retention and conductance characteristics compatible
with the method of the present invention. According to an aspect of
the present invention, at least one tube element 140 may take the
form of a fiberglass weave of elements, such as a 1 inch diameter
fiberglass weave, that draws water through a capillary action when
water is perched around, near, below, or above at least one tube
element 140.
[0029] Flow capacity values are the product of the hydraulic
conductivity and cross-sectional area of passive capillary drains.
These values give the volume of water per unit time that is
conducted through a capillary drain under a unit hydraulic gradient
as would occur in a vertically oriented installation. Flow capacity
for single strands range from 152 nearly 2000 cm.sup.3/hour, and
doubling the number of strands may increase the flow capacity
two-fold. Thus, a wide range of flow capacity values exist
resulting from the diversity of materials that may be used,
including a large array of fiberglass rope materials that are
commercially available.
[0030] As previously described, the exemplary embodiment of the
present invention utilizes fiberglass rope for accomplishing
capillary drainage. There are, however, a variety of materials that
may serve as tube element 140 including fiberglass tape, a weaving
or webbing of fiberglass or metallic strands having a rectangular
cross-section and contained column of sand or other mineral
particles does contain, which may consist of a tubular knitted mesh
filled with appropriately sized sand particles. These alternative
materials are wettable, contain a distribution of pore sizes that
are compatible with the root zone, have an adequate flow capacity
to allow timely removal of excess and perched water, and have a
structural integrity that would resist free water flow.
[0031] Referring now also to FIG. 2, there is shown a blowup of
core 150 and at least one tube element 140 of the present
invention. Core 150 of the present invention is designed to
increase the flow rate of water once contained in the passive
capillary and gravity drain. Core 150 may be made from a number of
materials or combinations thereof, such as stainless steel tubing,
flexible plastic tubing, ceramics, or other material capable of
moving water and allowing water to enter a drain. Core 150 may also
take the form of a plastic, or other suitable material that
provides drainage, tube with slits positioned to allow captured
fluids to enter the tub and be drained according to the present
invention. Several common materials may be found in the landscaping
industry, for example. According to aspect of the present
invention, core 150 may take the form of a 3/8 inch stainless steel
stint or tube, for example. According to another aspect of the
present invention, core 150 may take the form of a stainless steel
mesh core that carries drainage water away with high efficiency,
for example, during the first several hours following a heavy
rain.
[0032] Referring now to FIG. 3, there is shown a layout of the
present system 300 according to an aspect of the present invention.
As may be seen in FIG. 3, there are a multitude of capillary drains
310 forming a system according to an aspect of the present
invention. System 300 may include drains 310 formed on 3 feet
spacings and attached to a larger drain 320, or collection system
that is in turn connected to an outlet 330 for the drain water.
[0033] Referring now to FIG. 4, there is shown a comparison of the
present system to a conventional drainage system. A conventional
drainage system refers to a 2-inch perforated polymer pipe
configured with a 6 foot spacing. The present system, as compared
to ditch excavating with additional 2 inch plastic pipe systems,
allows for faster installation, is extremely cost effective, and
may provide a site-specific solution to treat only the low areas.
Further, the present invention may be installed at 3 feet spacing
for more consistent draining, dual acting gravity and capillary
action, to enhance existing drainage systems.
[0034] As may be seen in FIG. 4, the present capillary drainage
system 100 may handle more than 2.times. the amount of drainage
water in the initial four hours of drainage. Further, the capillary
drainage system 100 of the present invention may continue to work
as well as a conventional drainage system for the time 8-24 hours
after the drainage begins. The present invention provides superior
drainage during the first four hours and through the first eight
hours while maintaining equal or better drainage for the remainder
of the initial 24 hour drainage period.
[0035] FIG. 5 depicts the steps in a method 500 of moving water.
Method 500 includes capturing 510 a first plurality of the water in
a core and drawing 520 a second plurality of water into a tube
element. Method 500 may include removing 530 fluid that is perched
at the native soil interface using a sand curtain. Method 500 may
also include providing 540 a hanging water column to increase the
capillary forces used in fluid removal. Further, method 500 may
include draining 550 the captured fluid into an existing drain or
collection line.
[0036] The system and method of the present invention may be used
anywhere it becomes necessary to move water. For example, sports
fields, golf courses, foundations, bridges, construction areas,
rooftop gardens, planters, and other drainage areas may benefit
from the present invention. In the case of golf courses, the highly
effective drainage on chronically wet soils provides a benefit, in
addition to the benefit of the low cost and lack of use disruption.
The present system is extremely cost effective and may pay
dividends for schools, universities, and municipalities to improve
drainage and natural grass playing fields making maintenance easier
and less expensive.
[0037] The present system may be installed with a minimally
disruptive vibratory plow, allowing the elements of the present
system to be surgically placed at 3 feet intervals, leading to
better drainage.
[0038] In the case of horizontal installation, installation may
begin with a layout and cutting of an entry hole using a cup cutter
or similar tool. Using a vibratory plow with a special blade and
sand chute, a 1/2 inch sand curtain from 2 inches below the surface
to the top of the elements is installed. The elements of the
present invention may be installed 8 to 16 inches below the
surface. These lines run parallel at 3 foot spacing and move water
using capillary and gravity flow to a collection line or existing
drain. Once collected at a collection line or existing drain, a
drop may be incorporated to provide a hanging water column. This
hanging water column may provide for increased capillary suction.
Any size drop may provide the hanging water column, but a drop in
the range of 1 inch to 10 inches may provide the appropriate
capillary suction. More specifically, a drop of approximately 4-8
inches, or even more specifically approximately 6 inch drop may
provide the appropriate hanging water column.
[0039] In the case of a vertical installation, the capillary and
gravity drain installation may include a two-step procedure. First,
a pilot hole is created in the soil extending from the surface to
the maximum depth of drain insertion. Subsequently, the capillary
drain material is inserted into the pilot hole. As the pilot hole
needs to extend through both the sandy root zone and a layer of
fine gravel, it is desirable to employ a solid, pointed tip,
circular diameter tine to create the pilot hole of a diameter
slightly larger than the capillary drain. A mechanical actuator,
such as a hydraulic ram, for example, may be used to drive the tine
vertically into the soil and remove it leaving a pilot hole. To
facilitate insertion of a flexible capillary drain (such as a
fiberglass rope) to the desired depth, some added stiffening
support may be required. Enough stiffness may be obtained by
choosing the right material for the core 150. Inserting and
affixing a small diameter wire, plastic or wooden dowel into the
center and along the long axis of the rope may provide additional
stiffening support. The modified section of fiberglass rope may
then be inserted to the desired depth. The resultant cavity
extending from the soil surface to upper surface of the capillary
and gravity drain is then closed with tape, foam or other suitable
material. The still open space is backfilled with appropriate root
zone material.
[0040] The installation methods described above may also include
mechanization of the insertion process so that a single operator of
a small, motorized unit could, in a timely fashion, install an
array of drains within a green.
[0041] Additionally, the present invention may provide for the
ability to back pressure the drains using a pump thereby enabling
aeration of a soil or rootzone. Such aeration may be accomplished
by connecting a pump to the output, somewhere in the system
accessible while minimizing green/rootzone disruption, and
pressurizing the system to add and/or stimulate aeration of the
rootzone.
[0042] Although the invention has been described and pictured in an
exemplary form with a certain degree of particularity, it is
understood that the present disclosure of the exemplary form has
been made by way of example, and that numerous changes in the
details of construction and combination and arrangement of parts
and steps may be made without departing from the spirit and scope
of the invention as set forth in the claims hereinafter.
* * * * *