Encapsulated turf maintenance system

An underground fluid exchange system for control of delivery of fertilization, irrigation and pesticides to and removal from a selected fully encapsulated the turf area of a playing field, including golf course green, having a selected soil profile including a combination turf and topsoil turf segment, a porous soil segment and an impervious soil segment wherein the fluid exchange system comprises a bi-flow porous conduit having uniform porosity that has a selectable exchange rate.

BACKGROUND OF THE INVENTION 
1. Field of the Invention (Technical Field) 
The present invention relates to an underground fluid exchange system. In 
particular the invention is directed to a fluid exchange system to control 
delivery of fertilization, irrigation and pesticides to, and removal from, 
an encapsulated turf area of a playing field for increasing maintenance 
efficiency. 
The following is an example of turf maintenance programs and their 
environmental impact profile. Golf courses typically are actively 
maintained through daily inputs of fertilization, irrigation and 
pesticides in amounts that exceed the typical home lawn treatment. In 
particular golf greens typically require the maximum degree of inputs of 
maintenance effort and resources to the extent the level of input has 
become an environmental concern. This concern is directed to the degree of 
risk of contaminating surface or ground waters. This concern has led to 
conducting long term studies by the USGA including a so-called Cape Cod 
project that have demonstrated that golf courses can utilize chemicals and 
fertilizers effectively without contaminating ground or surface waters if 
proper prescribed procedures are followed. A case in point, when 
Integrated Pest Management (IPM) procedures are followed the potential for 
environmental contamination is virtually eliminated notwithstanding daily 
inputs of fertilization, irrigation and pesticides. All new golf course 
construction in Massachusetts requires a commitment to follow IPM 
procedures for golf course management. 
Accordingly there is a need to address the issue of reducing fertilizer, 
irrigation water and pesticide input, as well as, provide protection 
against contamination of surface and ground waters. This is particularly 
true with respect to golf greens, as well as other athletic playing 
fields. 
2. Background Prior Art 
In the past, attempts have been made to provide disposal arrangements for 
drainage of athletic playing fields. Applicant is aware of prior art turf 
maintenance devices, for example U.S. Pat. No. 3,908,385 to Purdue 
Research Foundation. The Purdue patent that shows a drainage system for 
rapid drainage of an athletic playing field having a drainage pipe 
combination adapted for vacuum pumping, but does not address the issue of 
reducing fertilizer, irrigation water and pesticide input as well as 
provide protection against contamination of surface and ground waters. 
Accordingly, there is a need in the turf art to address the issue of 
reducing fertilizer, irrigation water and pesticide input with respect to 
golf greens, as well as other athletic playing fields, which overcome at 
least some of the disadvantages of prior art. 
The present invention overcomes the limitations of the prior technology 
expressed above by providing an arrangement for encapsulating intensely 
managed turf areas, such as golf courses and athletic playing fields. 
Furthermore, the present invention totally restricts any leaching or 
movement of chemicals into ground waters, and directs all irrigation 
waters, fertilizer and pesticides by means of bi-flow conduit to a 
reservoir for recycling. 
SUMMARY OF THE INVENTION 
The present invention is directed to an underground fluid exchange system 
for control of delivery of fertilization, irrigation and pesticides to and 
removal from a selected fully encapsulated the turf area of a playing 
field. More specifically the preferred embodiment is directed to an 
encapsulated playing field consisting of a golf course green, having a 
selected soil profile. The soil profile comprises a combination turf and 
topsoil turf segment, a porous soil segment and an impervious soil segment 
wherein the fluid exchange system comprises a bi-flow porous conduit 
having uniform porosity that has a selectable exchange rate. 
Golf course greens are typically constructed to maintain maximum 
infiltration and percolation of water through rooting media. Root zone 
mixture composition recommended by the United States Golf Associate (USGA) 
generally includes at least 90% of sand by weight. This mixture allows for 
rapid water percolation but has an extremely low cation exchange capacity. 
These characteristics create a condition for potential movement and 
leaching of pesticides and nitrate to groundwater and may also cause 
surface water contamination. 
The present invention provides an enhanced environmental approach to golf 
greens construction by providing an encapsulation means for enclosing the 
entire golf green profile, including fluid exchange conduit for 
bi-directional sub-irrigation as well as drainage as required. The 
encapsulation means comprises an impermeable geo-fabric constructed to 
restrict any movement of water or dissolved materials from an underlying 
water table. The geo-fabric is positioned underground beneath the playing 
field, for eliminating the possibility of any materials leaching into 
surface or ground waters, with the result that the geo-fabric restricts 
any contamination of ground waters and surface waters adjacent the playing 
field. 
In the present invention, the fluid exchange apparatus comprising porous 
conduit positioned underground in a porous soil segment provides for 
controlling the transfer of chemical laden water between a turf and soil 
profile and a containment reservoir. Said conduit comprising a combination 
of activated charcoal and portland cement that can be selectively formed 
to yield a wide range of porosity, which is uniform in porosity through 
the length of the conduit. In the preferred embodiment the porosity-water 
flow is 5.0 gal/min. Due to the nature of the conduit, it acts as a 
gravity fed drainage as well as a sub-irrigation supply source, providing 
bi-directional movement of fluid. The nature of the walls of the conduit 
provides for filtration and eliminates fouling of the conduit by 
preventing soil fines entering and clogging the conduit. The porous 
conduit is positioned underground in the porous soil segment below the 
turf root zone, for controlling the transfer of fluids between the solid 
profile and the reservoir. This conduit also contains a continuous filter 
wall for selectively receiving filtered drainage fluid by gravity. Also, 
responsive to recycling pumping action, the conduit provides filtered 
subsurface irrigation to the root zone of the turf. 
A manifold is provided for connecting the porous conduit to the reservoir, 
which includes a pump means for transferring fluid from reservoir means to 
root zone of turf for improved root zone management. The reservoir means 
for receiving and storing all fluids introduced to the soil profile; for 
later transfer by said pump means to the root zone as required. 
Conventional Sensing and fluid control means, well known in the art, are 
employed to regulate the direction and rate of flow of water in the 
system. 
The present invention is particularly directed to providing an efficient 
means of implementing Integrated Pest Management (IPM) procedures for golf 
course greens management to eliminate the potential for environmental 
contamination notwithstanding daily inputs of fertilization, irrigation 
and pesticides. 
It is a general object of the present invention to provide a self-contained 
reservoir system for recycling irrigation water for reducing use of 
pesticides and providing improved root management of an athletic turf 
system. 
Another object of the invention is to provide a scheduling means for 
adjusting irrigation and fertilization to eliminate adverse impacts on the 
environment adjacent the golf green. 
Yet another object of the present invention to increase the efficiency of 
managing water for irrigation and fertilizer supply to a USGA Golf Putting 
Green to maintain the health of the green. 
A further object of the invention is to provide an efficient recycling of 
water and nutrients while totally restricting movement of materials to 
groundwater. 
These and other objects, advantages, and features of the invention will be 
apparent from the following description of preferred embodiments 
considered along with the accompanying drawings. The invention will be 
described for the purposes of illustration only in connection with certain 
embodiments; however, it is recognized that those persons skilled in the 
art may make various changes, modifications, improvements and additions on 
the illustrated embodiments all without departing from the spirit and 
scope of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the FIGS. 1-4, the preferred embodiment is directed to the 
inventive combination of a playing field 10 having a selected soil profile 
12 and a fluid exchange system 20 comprising a combination turf and 
topsoil turf segment 14, a porous soil segment 16, impervious liner 18 and 
an impervious soil segment 19. 
For comparison purposes, there is shown in FIG. 5 the standard profile of 
the United States Golf Association golf green that consists of three 
layers: root zone; coarse sand layer; and coarse stone drain layer. The 
root zone soil is composed of 80% fine sand and 20% peat organic material. 
The particle density of the root zone is 2.42 g/cm .sup.3 ; bulk density 
is 1.65 g/cm.sup.3 ; total porosity is 31.67; airfilled porosity was 
26.64%; and infiltration rate is 44.71 inch/hr. As is shown in FIG. 1, a 
4" perforated drain is provided in washed stone positioned below the 
washed stone blanket. 
Referring to FIGS. 1-4 there is shown schematic layouts of the fluid 
exchange system 20, "WIFS", showing a cross sectional view at a drainage 
field 22, the irrigation/drainage apparatus 24 of a selected playing field 
10 and a reservoir 26. As is shown in FIG. 1, fluid exchange system 20, 
"WIFS" shows four layers comprising a layer of topsoil and grass by 
"others" 14, porous soil layer 16, approximately 10" thick, wherein a 6" 
diameter Wilform Porous Conduit 30, having a 1" filter wall 32 is 
disposed; a layer of impervious liner 18 comprising an impermeable 
geo-fabric providing an encapsulation barrier; and a layer of impervious 
soil 19 compacted to an approximate depth of 6." 
Referring to FIG. 2 there is shown central longitudinal view of a section 
of porous conduit 30 positioned underground in the porous soil segment 16. 
Conduit 30 provides a means for controlling the transfer of water 40, 
shown in FIG. 4 between said turf and soil profile and a containment 
reservoir 42. As is shown in FIG. 2, conduit 30 comprises a combination of 
activated charcoal 42 and portland cement 44 which can be selectively 
formed to yield a wide range of porosity. In the preferred embodiment the 
porosity-water flow is 5.0 gal/min. Due to the nature of conduit 30, it 
acts as both a gravity fed drainage from the turf and soil profile and 
subirrigation supply source, providing bi-directional movement of water 
40. The nature of the filter wall 32 of conduit 30 provides for filtration 
and eliminates fouling of the conduit 30 by preventing soil fines entering 
and clogging said conduit. 
Referring to FIG. 3 there is shown a top schematic view of an 
irrigation/drainage area 41 showing the layout of conduit 30 shown as a 
plurality of rows piping 42 on 20" centers connected to control valves 44 
and in turn to supply 46 and return 48 lines 46 comprising solid piping 
which are connected to the reservoir 26 as is shown in FIG. 4. 
Tensiometers 50 are selectably located in said irrigation/drainage area 
Referring to FIG. 4 there is shown a sectional schematic of the containment 
reservoir 42 shown as a holding tank showing supply lines 46 to 
irrigation/drainage area 41 and return lines 48 therefrom. Also shown is a 
pump 60 shown successively in communication with check valve 62, automatic 
shut-off valve 64 automatic drain valve 66 and supply piping 46. An access 
man hole 68 is shown adjacent finish grade 70. Also shown is a tank 
make-up line with sensor 72, tank overflow line with sensor 74 and return 
piping 48 from irrigation/drainage area.