U.S. patent application number 13/960689 was filed with the patent office on 2014-02-13 for storm water filtration system using box culverts.
This patent application is currently assigned to KriStar Enterprises, Inc.. The applicant listed for this patent is KriStar Enterprises, Inc.. Invention is credited to Douglas Paul Allard.
Application Number | 20140042103 13/960689 |
Document ID | / |
Family ID | 50065402 |
Filed Date | 2014-02-13 |
United States Patent
Application |
20140042103 |
Kind Code |
A1 |
Allard; Douglas Paul |
February 13, 2014 |
Storm Water Filtration System Using Box Culverts
Abstract
An apparatus and method for use in conjunction with box culverts
to collect and filter or otherwise treat dirty or polluted storm
water runoff or other fluid is disclosed. One or more filter
devices with filter media is used in connection with a box culvert.
One or more internal bypass assemblies is disposed along a vertical
surface in the box culvert. One or more concrete slabs is installed
within the box culvert and forms a false floor below the filter
devices. The false floor provides an annular space through which
fluid can bypass the filter devices and be released to a drainage
system.
Inventors: |
Allard; Douglas Paul; (Santa
Rosa, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KriStar Enterprises, Inc. |
Santa Rosa |
CA |
US |
|
|
Assignee: |
KriStar Enterprises, Inc.
Santa Rosa
CA
|
Family ID: |
50065402 |
Appl. No.: |
13/960689 |
Filed: |
August 6, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61681097 |
Aug 8, 2012 |
|
|
|
Current U.S.
Class: |
210/747.3 ;
210/170.03 |
Current CPC
Class: |
E03F 5/106 20130101;
E03F 1/00 20130101 |
Class at
Publication: |
210/747.3 ;
210/170.03 |
International
Class: |
E03F 1/00 20060101
E03F001/00 |
Claims
1. A filtration apparatus comprising: (a) a culvert comprising an
inlet opening, a pair of opposing side walls, a pair of opposing
haunches, and a bottom slab; (b) a filter bay disposed within the
culvert, downstream from the inlet opening, the filter bay
comprising (i) a base member disposed above the bottom slab and
supported by the opposing haunches of the culvert, (ii) filter
medium resting on the base member, and (iii) a bypass channel
extending laterally between the base member and the bottom slab of
the culvert; and (c) a bypass structure disposed between the inlet
opening and the filter bay, the bypass structure comprising (i) a
first interior wall disposed on the bottom slab, (ii) a second
interior wall disposed on the base member and separated from the
first interior wall by a substantially hollow space, and (iii) a
fluid conveying apparatus extending laterally through a portion of
the bypass structure; wherein the inlet opening and the filter
medium are in fluid communication through the fluid conveying
apparatus of the bypass structure; and further wherein the inlet
opening and the bypass channel are in fluid communication through
the substantially hollow space of the bypass structure.
2. The filtration apparatus of claim 1, further comprising a gross
pollutant hood positioned in front of a portion of the first
interior wall.
3. The filtration apparatus of claim 1, further comprising a drain
down tube downstream from the inlet opening.
4. The filtration apparatus of claim 1, further comprising one or
more secondary culverts coupled to the culvert, each secondary
culvert comprising one or more filter bays.
5. The filtration apparatus of claim 4, further comprising one or
more substantially vertical separation plates disposed between
adjacent filter bays of adjacent culverts.
6. The filtration apparatus of claim 4, further comprising a
secondary culvert comprising an outlet section.
7. The filtration apparatus of claim 4, further comprising a shared
inlet pipe coupled to the inlet opening, wherein a secondary
culvert is adapted to receive fluid from the shared inlet pipe.
8. The filtration apparatus of claim 1, further comprising
secondary filter bays coupled to the filter bay.
9. The filtration apparatus of claim 1, further comprising an
access riser comprising a moveable access cover along a top surface
of the culvert.
10. The filtration apparatus of claim 1, further comprising a
plurality of bypass structures disposed within the culvert.
11. The filtration apparatus of claim 1, further comprising one or
more intermediate surfaces disposed between the first interior wall
and the bottom slab.
12. The filtration apparatus of claim 1, further comprising one or
more intermediate surfaces disposed between the second interior
wall and the base member.
13. An apparatus adapted to cooperatively engage with a culvert
comprising: (a) a culvert comprising one or more side walls, an
inlet opening along at least one side wall, and a bottom slab; (b)
a first chamber disposed within the culvert and downstream from the
inlet opening; (c) a second chamber disposed within the culvert and
downstream from the first chamber, the second chamber comprising a
base member, filter medium resting on the base member, and a bypass
channel extending laterally between the base member and the bottom
slab; (d) a bypass unit disposed between the first and second
chambers, the bypass unit comprising a first interior wall, a
second interior wall separated from the first interior wall by a
substantially hollow space, and a fluid conveying apparatus
extending laterally through a portion of the bypass unit; wherein
the bypass channel forms a route for storm water exceeding the
capacity of the first chamber.
14. The apparatus of claim 13, further comprising a gross pollutant
hood positioned in front of a portion of the first interior
wall.
15. The apparatus of claim 13, further comprising a drain down tube
in the first chamber.
16. The apparatus of claim 13, further comprising one or more
secondary culverts coupled to the culvert, wherein each secondary
culvert comprises filter medium.
17. The apparatus of claim 16, further comprising one or more
substantially vertical separation plates disposed between adjacent
culverts.
18. The apparatus of claim 16, wherein one of the secondary
culverts comprises an outlet section.
19. The apparatus of claim 16, further comprising a shared inlet
pipe coupled to the inlet opening, wherein a secondary culvert is
adapted to receive fluid from the shared inlet pipe.
20. The apparatus of claim 13, further comprising an access riser
comprising a moveable access cover along a top surface of the
culvert.
21. The apparatus of claim 13, further comprising a plurality of
bypass units disposed between the first and second chambers.
22. A method of processing fluid using a culvert comprising the
steps of: (a) selecting an inlet of a culvert, the culvert
comprising one or more side walls and a bottom slab; (b) passing
fluid from the inlet of the culvert to a first chamber disposed
within the culvert; (c) passing fluid from the first chamber
through a bypass unit comprising a first interior wall, a second
interior wall separated from the first interior wall by a
substantially hollow space, and a fluid conveying apparatus
extending laterally through a portion of the bypass unit; (d)
releasing fluid accumulating below the height of the first interior
wall through the fluid conveying apparatus of the bypass unit to a
second chamber disposed within the culvert, the second chamber
comprising a base member disposed above the bottom slab and filter
medium resting on the base member; and (e) releasing fluid
accumulating above the height of the first interior wall through
the substantially hollow space in the bypass unit to a channel
extending laterally between the base member and the bottom
slab.
23. The method of claim 22, further comprising the step of
separating gross pollutants through a floatables weir positioned in
front of a portion of the first interior wall.
24. The method of claim 22, further comprising the step of removing
fluid accumulating below the height of the fluid conveying
apparatus through a drain down tube positioned in the first
chamber.
25. The method of claim 22, further comprising the steps of
releasing filtered flows from the second chamber and releasing
unfiltered flows from the channel.
26. The method of claim 22, further comprising the step of passing
fluid exiting the culvert through one or more secondary culverts,
each comprising filter medium.
27. The method of claim 26, further comprising one or more
substantially vertical separation plates disposed between adjacent
culverts.
28. The method of claim 22, wherein the culvert comprises secondary
culverts coupled to the second chamber.
29. The method of claim 22, wherein the culvert further comprises
an access riser comprising a moveable access cover along a top
surface of the culvert.
30. The method of claim 22, further comprising the step of passing
fluid from the first chamber through a plurality of bypass
units.
31. The method of claim 22, wherein the channel between the base
member and bottom slab forms an alternate route for fluid flow.
32. The method of claim 22, wherein said the first chamber directs
fluid flow via an equalizing port.
33. The method of claim 22, wherein said the filter medium rests on
one or more recesses on a surface of the base member.
34. The method of claim 22, wherein a hole is used to position the
bypass unit at a substantially center portion of the base member.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/681,097 filed on Aug. 8, 2012, which is herein
incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to apparatuses and
methods for treating or filtering fluids, and more particularly to
apparatuses and methods for use in conjunction with box culverts to
collect and filter storm water runoff.
BACKGROUND OF THE INVENTION
[0003] Impervious surfaces and other urban and suburban landscapes
generate a variety of contaminants that can enter storm water,
polluting downstream receiving waters. These contaminants can
include heavy metals, oils, and greases, organic toxins, as well as
trash and debris. In response to tighter guidelines imposed by
environmental and regulatory agencies, the control of pollution,
silt and sediment found in storm water runoff and other sources of
water is receiving ever-increasing attention at all levels of
federal, state, and local government. Federal and state agencies
have issued mandates and developed guidelines regarding the
prevention of non-point source (storm water caused) pollution that
require action by governmental entities. These mandates affect the
management of water runoff from sources such as storms, slopes, and
construction sites. In addition, there are many other laws and
regulations in place that restrict the movement or disposal of
significant amounts of water. Such laws and regulations have a
significant impact on, for example, the ways that states,
municipalities, highway authorities and other responsible bodies
can drain or otherwise dispose of storm water runoff or other water
falling on or passing over highways, roadways, parking lots and the
like.
[0004] Typical storm water filtration systems used to reduce
pollutant loading in runoff from urban developments include known
filter devices housed in a vault configuration. The filter devices
capture and retain sediment, oils, metals and other target
constituents close the source and reduces the total discharge load.
As illustrated in FIG. 1, the filter devices can include
cylindrical filter cartridges with filter media, housed within
upright walls, such as the Perk Filter.TM. (KriStar Enterprises,
Inc.; Santa Rosa, Calif.). A filter device is also described in
U.S. Pat. No. 6,241,882, which is entitled "Sump & Filter
Device For Drainage Inlets" and is assigned to KriStar Enterprises,
Inc.
[0005] Referring to FIG. 1, storm water can enter the filtration
system via an inlet opening 101 through an outer wall 102 into a
first chamber of the vault. The first chamber includes a gallery
floor 103 and a floor slab 104 beneath the gallery floor. The storm
water then flows through one or more bypass manifold assemblies
105, past an internal wall 106 that is poured such that it is
monolithic with the outer wall or outer walls. The bypass manifold
assembly includes an inlet bypass floatable weir 107 at an upper
portion that obstructs the flow of gross pollutants in the water.
The bypass manifold assembly also includes an inlet bypass manifold
weir 108 located at a lower portion that allows fluid to
accumulate. During periods of routine flow, storm water moves
through the bypass manifold assembly into an adjacent filter
chamber, where it is filtered by one or more known devices, such as
filter cartridges 109 containing filter media. Filtered flows then
move through an outlet opening 110 along an outer wall 111. During
periods of peak flow, storm water is allowed to accumulate in the
first chamber until it reaches the height of the lower bypass weir,
also called an inlet bypass manifold weir. Bypass flows pass over
the weir and are directed to a lower annular space, separate from
the chamber with filter media, before the storm water exits the
system. Angled brackets support 112 acts as a support frame for the
platform on which the filter media rests. Expansion bolts 113 are
used to join the angled bracket to the platform.
[0006] Because the vault and the components must be separately
constructed, time and effort is required to size and manufacture
different vaults and components for different flow capacities.
Moreover, the platform on which the filter devices rest must be
sized and designed to securely fit these different vault
structures. In practice, the filtration capacity is often limited
by the size of an individual vault. Installation of the various
components in the system may require additional effort,
particularly for larger systems with a large number of filter
devices and increased treatment capacities.
[0007] Thus, there exists a need for practical and economical storm
water filtration methods and apparatuses that can be easily
manufactured and installed at a site. There is also a need for a
storm water filtration system that can efficiently handle bypass
flows during peak events. There is also a need for a storm water
filtration system that can be configured to handle different levels
of storm water flows.
SUMMARY OF THE INVENTION
[0008] The present invention provides more effective methods and
apparatuses for filtering and treating polluted or dirty water,
such as storm water runoff, using existing box culverts. The
invention relies on the support structures in the box culvert to
install a "false floor" that supports the filter media and allows
filtered flows to pass along the top. The false floor also creates
an annular space below to allow for unfiltered bypass flows from
the system.
[0009] A conventional box culvert includes a rectangular-shaped
drain or pipe that channels water flow under roads, parking lots,
railroads, or similar obstructions. Other shapes such as arched,
round, circular, or curved culverts are also available. Box
culverts are generally available as precast units that can be
manufactured before installation. They provide both load bearing
strength and structural integrity. Because they are readily
available and easily sourced for construction applications, box
culverts provide a versatile, structurally strong, and cost
effective structure to support storm water filtration systems. Box
culverts are available in various standard sizes and known
materials, such as precast concrete. Thus, one advantage of the use
of a box culvert in the present invention is the ability to use
existing structures that are available and manufactured according
to standard industry sizes. This allows for ease of manufacture, as
well as quicker and more economical installation.
[0010] Another advantage of the present invention is the use of one
or more false floors installed in an existing box culvert to
provide a separate, alternate path for storm water flow. A false
floor is set within the box culvert. It provides a platform or
mounting surface on which filter devices may rest. It also creates
an annular space beneath the floor through which unfiltered flows
moving from the bypass assembly can move. In this way, the false
floor separates filtered and unfiltered storm water flowing through
the same system.
[0011] Another advantage of the present invention is the
flexibility to configure and use additional filter sections in box
culverts, as needed for a given site or filtration capacity.
Because the box culverts are modular, a plurality of box culverts
may be used in different configurations, depending on the needs of
a given site or construction project. The system can be expanded to
accommodate multiple units. In addition, filter units can be added
or removed as needed.
[0012] Another advantage of the present invention is the use of one
or more internal bypass assemblies disposed within one or more
walls of the inlet section. The internal bypass assembly provides
an alternate path for storm water during peak flow events by
diverting storm water from a filter section into an annular space
below the filter section.
[0013] A further advantage of the present invention is the
reduction of the workload required of one more particular filter
unit in terms of the amount of sedimentation, silt and pollution
that they are required to remove over the course of its life span.
These advantages can be accomplished by installing multiple filter
banks, such that at least a portion of storm water runoff or other
passing fluids can be processed through multiple banks during high
flow events.
[0014] Another advantage of the present invention is the ability to
retain gross pollutants, such as trash, debris, and coarse
sediment, within a filtration system, without impeding peak flow
bypass needs. The present invention allows for trash capture
through the use of a bypass manifold assembly located within a box
culvert.
[0015] Yet another advantage of the present invention is the
provision of more effective methods and apparatuses for filtering
and treating polluted or dirty water, such as storm water runoff,
that passes over highways, roadways, parking lots and the like,
such that whatever fluid eventually makes its way into a final
drainage infrastructure or destination is likely to be cleaner.
This advantage is realized by providing an apparatus and method for
processing water runoff or other fluid when such fluid enters a
water treatment system. These and other useful objects are achieved
by the improved apparatuses and methods disclosed herein.
[0016] One embodiment of the present invention provides an
apparatus adapted to cooperatively engage with a box culvert,
comprising: an inlet section disposed within a box culvert; at
least two outer walls shared with the box culvert; at least one
internal bypass assembly disposed within a wall of the inlet
section comprising two substantially vertical weirs; at least one
filter section in fluid communication with the bypass assembly
comprising at least two inner walls and filter media; at least one
bottom platform disposed within the box culvert and under at least
a portion of the filter section, wherein the space between a lower
surface of the platform and an upper surface of the box culvert
forms an annular space through which unfiltered fluid is allowed to
flow; and an outlet section in fluid communication with the filter
section, wherein said outlet section comprises at least two outer
walls shared with a box culvert.
[0017] Optionally, the apparatus may comprise an access riser along
a top surface of the box culvert, wherein the access riser includes
a moveable access cover. The apparatus may further comprise
multiple filter sections, wherein a substantially vertical
separation plate is disposed between adjacent filter sections. The
apparatus may further comprise multiple bottom platforms, wherein a
closure plate separates adjacent platforms. The platform of the
apparatus may optionally comprise concrete.
[0018] In another embodiment, the present invention provides a
method of processing fluid comprising the steps of selecting an
inlet of a box culvert; selecting a filter device; coupling said
box culvert and said filter device; installing a platform disposed
within the box culvert and under the filter device, wherein the
surface of the platform rests on a surface of the box culvert; and
passing fluid through said box culvert and filter device. The space
between a lower surface of the platform and an upper surface of the
box culvert forms an alternate route for fluid flow.
[0019] In some embodiments, it is contemplated that the dimensions
and structural configurations of the box culvert and filter
elements can vary with a range dependent on one or more design
factors including but not limited to: desired water volume
capacity, desired weight of each modular unit, desired load-bearing
tolerance for each unit, desired amount of water flow to be
managed, size and structure of overall assembly in which the system
is to be used, and/or the desired access space for inspection and
maintenance purposes. Other apparatuses, methods, features and
advantages of the invention will be apparent to one with skill in
the art upon examination of the following figures and detailed
description. All such additional apparatuses, methods, features and
advantages are included within this description and are encompassed
within the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The included drawings are for illustrative purposes and
provide examples of possible structures for the disclosed inventive
storm water filtration system. These drawings in no way limit any
changes in form and detail that may be made to the invention by one
skilled in the art without departing from the spirit and scope of
the invention.
[0021] FIG. 1 illustrates a side cut-away view of a known
filtration system using a vault configuration.
[0022] FIGS. 2A through 2C illustrate in top plan view, side
cut-away view, and end view, respectively, a filtration system
using box culverts with five treatment bays, an inlet section, and
an outlet section. FIG. 2D illustrates in side cut-away view of an
embodiment of a bypass assembly shown in FIGS. 2A through 2C.
[0023] FIG. 3 illustrates a top plan view of an exemplary
filtration system with four banks
[0024] FIG. 4 illustrates in side cut-away view of a bank of the
filtration system described in FIG. 3.
[0025] FIG. 5 illustrates schematically a section placement diagram
showing the filter units described in FIGS. 3 and 4.
[0026] FIGS. 6A through 6D provide isometric views of one
embodiment of a false floor of the present invention with recesses
for four substantially cylindrical filter devices.
[0027] FIGS. 7A through 7D provide isometric views of another
embodiment of a false floor of the present invention with recesses
for eight substantially cylindrical filter devices.
[0028] FIGS. 8A through 8D provide isometric views of a further
embodiment of a false floor of the present invention with recesses
for sixteen substantially cylindrical filter devices.
[0029] FIGS. 9A through 9D illustrate one unit, a short end cap,
made of standard concrete.
DETAILED DESCRIPTION
[0030] In the following detailed description, references are made
to the accompanying drawings, which form a part of the description
and in which are shown, by way of illustration, specific
embodiments of the present invention. Although these embodiments
are described in sufficient detail to enable one skilled in the art
to practice the invention, these examples are not limiting. Other
embodiments may be used, and changes may be made without departing
from the spirit and scope of the invention.
[0031] One embodiment of the present invention includes a
filtration system with multiple filter sections, each section
containing filter media that forms a treatment bay for incoming
storm water. The filtration system is incorporated into a precast
box culvert with a standard industry design. The box culvert is
shown as a large pipe structure having a rectangular cross section,
but in practice, the box culvert may have any other size and shape
common known in the art, such as round, elliptical, circular or
curved.
[0032] As shown in FIGS. 2A through 2C, storm water may enter the
system from an inlet, for example, an opening with an entrance pipe
201, and flow through an inlet section 202. The ordinary artisan
will recognize that all or a portion of the top faces of each box
culvert unit (alone or as part of a larger assembly) can be fitted
with or easily adapted for fitting with a cover panel, plug, plate,
grate, fitting or valve system well known in the art of water
management systems. As illustrated, the inlet section includes a
bolted and gasketed access cover 203 and access riser 204 with a
ladder. The presence of this port allows for inspection, clean-out,
monitoring, and maintenance of the inlet section.
[0033] One or more inlet bypass assemblies 205 are located within
the inlet section. The bypass assembly includes two substantially
vertical weirs. A first weir is located at a lower portion of the
assembly and forms a barrier to the flow of storm water entering
the inlet section and against which storm water can accumulate. The
second weir is behind the first weir, preferably positioned such
that the top edge of the second weir is higher than the top edge of
the first weir. The first weir can be located in front of the
second weir to first capture gross pollutants such as trash or
debris. A floatables weir, which can also take the form of a gross
pollutant hood, can be optionally located at a top portion of the
assembly and at least partially obstructs the passage of trash and
floatables to the adjacent chambers. One or more steel plates may
be used for or as part of one or more weirs. In addition, one or
more pipes or flow thru tubes may be positioned through slots in
the weirs to convey fluid to the filter sections. In a preferred
embodiment, two flow thru tubes may be incorporated to direct flow
in a given bypass assembly. One or multiple bypass assemblies can
be positioned within the interior of a box culvert, downstream from
the inlet opening. One or multiple bypass assemblies can be placed
side by side along a wall in the inlet section. One or more filter
sections 206 are placed downstream from the inlet section. An
equalization port 207 is placed in the inlet section (and in the
outlet section, as well).
[0034] During periods of normal flow, storm water flows from the
inlet section through the bypass assembly and toward downstream
filtration media, where it is treated using filtration methods
known in the art, including filter devices with filter cartridges
or perforated sand pipes. In one embodiment, the filter devices may
be cylindrical in shape and manufactured from durable polymeric
components with a polymer-coated steel support screen and stainless
steel hardware. Its base construction allows use with a wide
variety of media chose to address site-specific pollutants of
concern. Additional access covers 209 and access risers with steps
210 or ladder 211 can be included in the filter sections. The
presence of these additional ports allows for inspection,
clean-out, monitoring, and maintenance of the filter sections.
[0035] Subsequent filter sections of the system may be built into
individual box culverts or culvert segments placed side by side. To
connect the segments, tongue and groove joints 212 are sealed with
asphalt mastic and non shrink grout on the inside surfaces. An
outlet section 208 is located at an end of the filtration system
and includes an outlet 213 for storm water to exit the system.
[0036] As shown in FIG. 2C, the cross section of box culvert may be
rectangular in shape. The box culvert has opposing sides and curved
haunches 214 at the corners. When positioned along one or more
lower corners, the haunches or shoulders of the box culvert provide
a load-bearing surface to support a concrete slab that creates a
false floor 215. The false floor may be made of concrete or other
suitable materials. It is placed substantially horizontally above
the bottom of the box culvert and creates an annular space between
the bottom of the false floor and the bottom surface of the box
culvert. During periods of routine water flow, storm water moves
through the three openings from the bypass assemblies to one or
more filter sections for treatment. But during periods of high
flow, storm water that has accumulated above the height of the
second weir travels from the entrance of the inlet section into the
space between the two weirs, bypasses the filter section, and exits
through the outlet section or an alternative external bypass
structure (such as a separate pipe).
[0037] When multiple filter sections are included, as shown in FIG.
2A and 2B, stainless steel false floor connector plates 216 can be
used to connect false floors placed in adjacent filter
segments.
[0038] An embodiment of the bypass assembly is shown in more detail
in FIG. 2D. Under normal flow conditions, storm water from an
entrance of the system flows toward the first weir 216 and second
weir 217. The storm water rises to the level of one or more flow
thru tubes 218. A floatables weir 219 is positioned in front of an
upper portion of the first weir and captures gross pollutants from
the incoming storm water. Storm water--i.e., "low flows"--passes
through one or more of the tubes to the filter medium 220. The
floatables weir may be particularly advantageous in a system
because allows the use of cartridges in the filter section without
protection from floatable debris. During increased flow events,
storm water passes over the first weir, into the space between the
first and second weirs, and underneath the false floor. In a
preferred embodiment, a perforated drain-down feed-thru tube is
placed along or near one of the upwardly extending weirs. Because
the lowest flow path from the inlet section to either the filter
section or the bypass assembly can be above the floor, there is the
potential for standing water. The perforated drain-down feed-thru
tube allows that water to drain down into the filter section after
the rain event has passed.
[0039] The design of the filtration system of the present invention
is scalable. Because the box culverts are modular and can be added
as needed, the filtration system can be assembled in various
configurations to accommodate relatively high fluid flow along a
space. FIG. 3 illustrates one embodiment of the present invention
that uses three hundred and sixty-eight (368) filter cartridges,
each standing about 18 inches tall. The system includes box
culverts with an internal space in the shape of cubes that houses
the inlet and filter sections. The box culverts are configured to
form four substantially rectangular filter banks, 301, 302, 303,
and 304, each receiving storm water from inlet 305. As a
non-limiting example, each bank can be about 55 feet (660 inches)
long and 9.33 feet (112 inches) wide. The footprint of the system
can be about 55 feet long (660 inches) and 37.33 feet (448 inches)
wide.
[0040] Storm water enters through an inlet section 306. One or more
inlet bypass assemblies 307 are located downstream from the
entrance of each bank. In a preferred embodiment, three bypass
assembles are placed in each of the four banks, providing for a
total of twelve bypass assemblies. The inlet sections include
equalizing boot couplers, 308 and 309. During periods of routine
flow, storm water moves from the inlet section through the bypass
assembly, after which it is filtered by filter cartridges 310
placed in the filter sections 311. The filtered flows are directed
to one or more outlet sections 312, which also include one or more
equalizing boot couplers 313, and exit the system through an outlet
314 located on one side. False floors disposed within the box
culverts under the filter cartridges provide a secondary route for
unfiltered bypass flows during period of high storm water flow.
Stainless steel connecting plates 315 join false floors from
adjacent filter sections. By way of example, a filtration system
configured in this way may be designed to handle a treatment flow
rate of about 6,624 gallons per minute (14.76 cubic feet per
second) and a bypass flow rate of about 15.9 cubic feet per
second.
[0041] In this embodiment, storm water enters through a single
inlet; filtered and unfiltered exits through a single outlet.
However, the system can be configured to accept flow from
additional inlets and additional outlets, such as external pipes or
other structures. For example, unfiltered bypass flow can be
directed to a separate pipe or manifold, from which it would then
exit the system.
[0042] Notably, the system of the present invention allows for
flexibility in the event that additional capacity is needed after
installation. Although the filter banks are shown in the figures to
be populated, in practice, some of the filter banks may be left
vacant. Plugs, such as stainless steel separation plates or other
dividers, can be provided to isolate those unused banks during
operation. As the filtration needs of a particular site increases,
filter devices with additional media may be added in the previously
unused banks, and the plugs can be removed to increase the
filtration capacity of a given system.
[0043] FIG. 4 shows an assembled side cut-away view of an installed
system, as described in FIG. 3. The system is placed on bedding 401
that conforms to American Public Works Association ("APWA")
Standard Specification, Section 306-1.121, except that the minimum
bedding depth shall be 12-inches or greater. Backfill added around
the side and top 402, conforms to APWA Standard Specification,
Section 306-1.121, except that the minimum side backfill width
shall be as required to allow sufficient room for compaction but no
less than 6-inches and the minimum final backfill depth should be
12-inches. Compacted soil 403 may be placed above the filtration
system.
[0044] For cleanout and maintenance, bolted and gasketed access
covers 404 may be integrated using field poured concrete collar.
The access covers may be lifted to allow for maintenance,
clean-out, or monitoring of a filter section. In this way, the
filtration system will not be clogged. Additional access risers
with steps 405 or a ladder 406 can also be included to facilitate
access into and out of a particular unit.
[0045] Between individual filter sections, tongue and groove joints
407 are sealed with asphalt mastic and non-shrink grout on one or
more inside surfaces. It is contemplated that in some embodiments,
further connecting means or fastening means may be provided for
securing the box culverts. For example, wires, plastic ties,
fasteners (e.g., screws, rivets, nails, snap-clips, and the like)
or adhesive means (e.g., tape, glue, and the like) may be used to
secure box culverts. FIG. 5 is a diagram showing the section
placement of the units in each filter bank.
[0046] The present invention uses the haunch or shoulder of the box
culvert as a load-bearing surface, to support a false floor. This
assembly provides for a more economical design, as available
standard precast concrete box culverts may be used. It can also
eliminate the need for separate piping and the accompanying
hydraulic issues that may arise, as bypass flows can be directly to
the annular space under the false floor.
[0047] As shown in more detail in FIG. 6, a false floor can be made
of one or more slabs of suitable material, such as concrete. The
pre-existing structure of the box culvert provides a supporting
surface that can be used to support a false floor. At the two ends,
the false floor includes top and bottom chamfers located along the
shorter top and bottom sides 601 and 602. Each chamfer is set at
about a 45-degree angle to the adjacent face. The angles of the
chamfers match those of the corresponding haunches in the box
culvert. During installation, the chamfers are aligned with the
haunches of the box culvert to slide the false floor so that it
rests in within the box culvert. Epoxy can be used to fill in the
annular space between the false floor and box culvert to create a
seal and prevent leakage. When a system includes multiple false
floors, closure plates can be used to fill in the gaps between
adjacent false floors.
[0048] The false floor includes one or more cartridge impression
forms 603 that create recesses, on which filter cartridges can
rest. Threaded insert forms 604 are also included to be used with
threaded inserts. Because of it relatively compact size, this false
floor with four filter recesses may be placed at an outlet section,
next to an outlet pipe.
[0049] Another embodiment of the false floor of the present
invention is shown in FIGS. 7A through 7D. The false floor is made
of standard concrete. Chamfers 701 and 702 located at the ends of
the false floor can be designed to align with the haunches of a box
culvert (not shown). Cartridge impression forms 703 located on the
upper surface of the false floor create eight circular indentations
on which eight circular filter cartridges can securely rest. Insert
forms 704 are located along a side for threaded inserts. A through
hole 705 can be placed at the center of the slab to secure the
bypass assembly. Four standard lift eyes 706 can be placed along a
wall to facilitate transport. This false floor, which includes
eight filter recesses, may be placed next to one or more bypass
assemblies in an inlet section of a filtration system.
[0050] Yet another embodiment of the false floor with additional
filter cartridges is shown in FIGS. 8A through 8D. Chamfers 801 and
802 located at the ends can be designed to align with the haunches
of a box culvert (not shown). Cartridge impression forms 803
located on the surface of false floor create sixteen circular
indentations on which sixteen circular filter cartridges can
securely rest. Threaded insert forms 804 and 805 are located along
two sides for threaded inserts. Through holes 806 and 807 can be
placed at the center of the slab to secure one or more bypass
assemblies. Four standard lift eyes 808 can be placed alone a wall
to facilitate transport. This false floor may span the length, or
at least the partial length, of a filter section.
[0051] FIGS. 9A through 9D shows an embodiment of a short end cap
unit that can be installed in a box culvert, for use in the
filtration system of the present invention. Installation of this
unit can involve a series of concrete pours to secure components of
the system. In the first pour, the walls and end slabs 901 are
secured. In the second pour, the internal wall 902 is set in place.
In the third pour, a gallery wall along the bottom (not shown) can
be set. Heavy-duty lift eyes 903 are placed along the side walls to
facilitate transport of the systems. The walls surrounding the
aperture along a side, which can be offset to form a "stepped can,"
may include two layers resulting in outside 904 and inside 905
walls.
[0052] The components of the present filtration system, including
the bypass assemblies, false floor, filter sections, and banks can
be placed in different positions and configurations to address
storm water management needs along different surfaces and around
different surface structures. For example, the false floor can be
installed along side walls or underneath vertical walls. Different
filter media known in the art may be used. In addition, the
filtration system may be used alone or in connection with other
storm water management devices to increase the capacity and improve
processing of storm water. The box culverts may be attached to a
retention or detention system for water storage. As a further
embodiment, a method of telemetric monitoring can be incorporated
into the systems to better manage water flows.
[0053] Although the foregoing invention has been described in
detail by way of illustration and example for purposes of clarity
and understanding, it will be recognized that the above described
invention may be embodied in numerous other specific variations and
embodiments without departing from the spirit or essential
characteristics of the invention. Certain changes and modifications
may be practiced, and it is understood that the invention is not to
be limited by the forgoing details, but rather is to be defined by
the scope of the appended claims. Various modifications,
alternative constructions, design options, changes and equivalents
will readily occur to those skilled in the art and may be employed,
as suitable, without departing from the true spirit and scope of
the invention. Such changes might involve alternative materials,
components, structural arrangements, sizes, shapes, forms,
functions, operational features or the like.
* * * * *