Erosion control barrier

Abstract

An erosion control roll including an elongate core member defining an interior space, being open at both ends, and having openings along its length, a pervious filter member open at both ends and surrounding the elongate core member; and, an apron disposed on the upstream side of the pervious filter member, said apron running the length of said filter member, and extending a predetermined distance therefrom.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 60/628,430, filed Nov. 16, 2004 (Nov. 16, 2004).

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not applicable.

TECHNICAL FIELD

The present invention relates generally to soils erosion control barriers, and more particularly to an erosion control barrier in which water runoff is diverted via the barrier to a remote point of discharge.

BACKGROUND INFORMATION AND DISCUSSION OF RELATED ART

Controlling soil erosion, such as erosion on slopes at construction sites, and particularly control of the sedimentation and debris carried in fluid flow on slopes is a continuing problem. Fiber rolls (also known as wattles) are the current industry standard for use in controlling erosion. Fiber rolls are typically made of fibrous materials such as straw or excelsior (shredded wood) made into rolls that are held together with netting. During construction, the rolls are placed across the face of a slope to curtail soil erosion and to direct and/or filter fluid flow as the fluid flows down the slope. Silt fences, generally black porous cloth strung vertically on wooden stakes across a slope, are an alternative means of controlling erosion. However, most regulatory agencies now discourage the use of silt fences alone due to the propensity for silt fences to collapse from high fluid flows and high winds.

Fiber rolls have been found to be more capable of performing the erosion control function than silt fences. However, fiber rolls are deficient in their ability to direct fluid flow in a controlled manner. Moreover, numerous fiber rolls are generally required due to their inherent deficiencies in directing fluid flow as the flow proceeds down a slope.

An improved fiber roll is disclosed in commonly owned U.S. Pat. No. 6,527,477, to Allard. The '477 patent discloses a fiber roll wattle with a core member defining an interior space. One or more openings in the wall of the core member communicates with the interior space and allows fluids reaching the fiber rolls to enter the core member through said openings. The core member may comprise a flexible plastic pipe, such as high density polyethylene pipe having a plurality of perforations. By providing such an interior space, the erosion control roll not only serves as a barrier to erosion, but redirects hillside runoff to a point of discharge remote from the point of collection, such as when a multiplicity of rolls are linked one to the other by couplers to provide a continuous flow path to, for example, drain pipes associated with the connectors, or to the far terminal ends of the linked rolls. In the embodiment illustrated in the patent, outlet pipes are connected to the tee/elbow connectors used to connect the rolls longitudinally, the outlet pipes directing the fluid flow received by the core members to desired downstream locations.

Yet another improved erosion control wattle is described in commonly owned U.S. Pat. No. 6,641,335, to Allard, naming the first named inventor of the present invention. The '335 patent shows a walled elongated core member having a first open end, a second end, an interior space and one or more openings in the wall communicating the interior space with the exterior of the core member. A fiber roll outer filter member surrounds the core member, which can be coupled with to one or two complimentary core members comprising tee connectors or elbow connectors. One advantage of the present invention is the ability to connect outlet pipes to tee or elbow connectors for directing fluid flow received by the core members to desired locations downstream of the core members.

The foregoing commonly owned patents reflect the state of the art devices of which the present inventors are aware. Reference to, and discussion of, these patents is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein. Specifically, although each of the patents show improved barriers to intercept and divert water away from the barrier, there remains a problem with soil erosion in the area adjacent and around, underneath and downstream of the erosion rolls caused by water flowing to, over and underneath the rolls.

BRIEF SUMMARY OF THE INVENTION

The erosion control barrier of the present invention represents yet another significant advance over the fiber roll wattles in the prior art. The present invention includes a walled elongate core member having a first open end, a second open end, an interior space, with one or more openings in the wall communicating the interior space with the exterior of the core member, and further including an outer, pervious filter member which surrounds the core member. In one embodiment, the outer filter member includes an apron which is affixed to the filter member along its length, and extends outwardly away from the core member. The apron is of a predetermined width, and includes means to secure the apron upstream of the elongate core member, so as to cover the ground adjacent said member, and direct fluid runoff and sediments to the elongate core member. Fluids passing through the pervious outer filter and through the openings in the wall of the elongate core member are carried by the core member to discharge points at the end of the core member.

The inventive apparatus (variously referred to herein as the inventive “erosion control roll” or the inventive “erosion control barrier”) may used in conjunction with a silt fence deployed in abutting relationship to the control roll. The stakes used in the deployment of the silt fence serve the secondary purpose of providing additional stabilization for the control roll. The silt fence can be formed integral to the control roll, in which event the silt fence extends from the downstream side of the filter member, in the opposite direction of the apron, and is provided with holes sized to receive securing ground stakes. In another embodiment the upstream apron may be covered with earth, to provide additional ballast for system fixation and stabilization.

As with the erosion control rolls of the above-indicated commonly owned patents, two or more core members may be connected together. Accordingly, one or both of the open ends can be fitted to couplers or connectors for connecting one core member to another. The couplers can comprise tee connectors or elbow connectors, which allows for the connection of outlet pipes to the tee or elbow connectors for re-directing fluid flow received by the core members to desired locations downstream of the core members.

It is therefore an object of the present invention to provide a new and improved erosion control barrier roll that provides runoff water diversion and filtering.

It is another object of the present invention to provide a new and improved erosion control roll that reduces soil erosion around, underneath and downstream of the erosion control roll caused by water flowing to, over and underneath the roll.

A further object or feature of the present invention is a new and improved erosion control barrier that filters water differentially, depending on the materials suspended in the water, the amount of sedimentary deposit around the roll, and the water depth adjacent the roll.

There has thus been broadly outlined the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form additional subject matter of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based readily may be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIG. 1 is a perspective view of a section of the erosion control barrier of the present invention;

FIG. 2 is a perspective view of the roll of FIG. 1, further including a fabric section deployed to form a silt fence;

FIG. 3 is a side view in elevation of the embodiment of FIG. 2 shown deployed on a sloping surface;

FIG. 4A is a front view of an exemplary corrugated member suitable for use with the erosion control barrier of the present invention;

FIG. 4B a sectioned view illustrating a distribution of openings in the core member of FIG. 4A according to an embodiment of the invention;

FIG. 5 is a perspective view of the erosion control barrier of FIG. 1, but having additional features; and

FIG. 6 is a side view in elevation of an alternative embodiment of the erosion control barrier of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 through 6, wherein like reference numerals refer to like components in the various views, there is illustrated therein a new and improved erosion control barrier. The erosion control barrier of the present invention is adapted for use in controlling sedimentation and debris flow, especially in connection with construction site and hillside runoff. In its most essential aspect, the apparatus includes a hollow core member covered with an outer filter member incorporating a longitudinal apron which serves several purposes: It provides means to secure the hollow core member to the ground; it directs fluid flow to the core member; and it covers the ground adjacent the core member to prevent soil erosion around and beneath the core member. The present invention is particularly useful in controlling erosion resulting from sedimentation and debris flow on slopes at construction sites and other areas where soil erosion poses environmental issues.

Referring now to FIG. 1, a first embodiment of the present invention is shown to include an elongate walled core member 10, such as a perforated pipe, covered by a filter member or sleeve 12. The core member 10 is open at each end. As illustrated, core member 10 may extend beyond the edges of filter member 12 with which it is covered. However, in another embodiment filter member 12 may be fabricated to overlap and extend beyond the end or ends of core member 10. Preferably the filter member and the accompanying apron 14, as later described, extend a sufficient distance beyond each end of the core member so as to cover over any connectors (likewise later described) which may be used, and therefore to provide a continuous sleeve/apron combination extending the length any number of roll segments connected in series.

As will be appreciated, the perforations in the perforated pipe of the core member may have perforations circumferentially spaced openings at points along its length. However, any configuration or scheme adapted for selectively filtering fluids containing sediments and large pieces of debris may be employed.

The perforated pipe may be constructed of generally flexible material to facilitate the lay out of the erosion control barrier in a manner that closely follows the contours of the slope to be stabilized. It may also be corrugated, as illustrated in the figures. Accordingly, the core member may be made of any suitable stable, non-toxic and lightweight material, such as flexible high density polyethylene, polypropylene, polyvinyl chloride, polyester, or nylon pipe. Hollow core member may be comprised of perforated polymeric pipe element or semi-rigid netting. Perforation size may vary widely with application and material.

The filter member 12 covering core member 10 may be made from any pervious (i.e. porous/permeable) filter fabric, such as a woven or non-woven geotextile fabric, or a permeable polymeric matrix. Materials include polypropylene, polyethylene, polyester, natural cotton or other similar geotextiles and polyethylene fiber mat. Densities generally range, but may not be restricted to, 3-16 oz/sf. Geotextile materials may be woven, nonwoven, needle-punched or knit, while fiber mat may be woven, stitched or spun-bonded. Geotextile fabrics are typically made from polyester or polypropylene fibers. An exemplary woven geotextile fabric useable with the rolls of this invention is FILTERWEAVE® available from TC Mirafi Company, Pendergrass, Ga. Such geotextile fabrics generally have a porosity AOS (Apparent Opening Size) factor of not less than 180 μm, to permit the flow of water therethrough, while at the same time filtering out larger sediments, fines and other debris. The porosity of such fabrics is generally not less than 70 gpm/sq ft.

The filter sleeve and apron can be integrally formed from separate pieces or the same piece of geo textile fabric, or from different geo textile fabrics. By way of illustration, with reference to FIG. 1, apron 14 can be formed from the same geo textile fabric as filter member 12, by folding over a section of a selected rectangular fabric piece, the folded-over section equal to predetermined width 16 of apron 14, with seam 18 stitched at the leading edge 20 of the apron, and seam 22 stitched at the trailing edge of the apron and overlapping the other end of the geo textile fabric piece. It is to be appreciated that the total width of the fabric piece to be used to form the filter sleeve/apron should be such that the tubular pocket formed in the fabric piece by seam 22 is suitably sized to easily and securely receive the perforated pipe. It should be appreciated that the apron may alternatively be formed from a separate section of fabric and sewn to the filter sleeve. In such a case, the apron material may, but need not be the same as the material used to form the filter sleeve.

If desired, the leading edge of the apron can be provided with a reinforced edge. The reinforcement can be provided by sewing in or otherwise securing a rigid member proximate the leading edge. For instance, a steel rod or geogrid can be sewn into the leading edge, in a manner well known in the art. Such reinforcement helps to maintain contact of the apron with the uphill ground surface, from the apron's leading edge to the midpoint of the filter member.

The apron can also be provided with a plurality of holes 26 fitted with protective grommets so as to allow for the insertion of metal pins or nails 27 to secure the apron to the ground. Alternatively, the apron can be secured to the ground surface on which the assembly is placed with U shaped staples or stakes.

With reference to FIG. 2, a second preferred embodiment of the erosion control barrier of FIG. 1 shows that the core member and apron can be used in conjunction with a silt fence 28 deployed in an abutting relationship to the core member and apron. The silt fence may be formed of the same geotextile fabric as the filter sleeve, but more likely will be formed from less pervious or non pervious material. The silt fence 28 can be integrated with the filter sleeve member by being sewn to the member. Alternatively, when the same geotextile material is used for the filter member, the apron, and the silt fence, the geotextile fabric piece selected to fabricate the assembly will be sized so as to allow for the formation of the silt fence, the filter member, and the apron from a single piece of fabric. Silt fences are typically about 36″ high. Thus to form the combined silt fence/filter member/apron assembly, a longitudinal seam is provided at a point about 36″ from one edge of the fabric piece, to define the fence portion and a suitably sized pocket seamed to received the perforated pipe. A multiplicity of sleeves 30 are provided, stitched to the textile fabric piece 28 and arranged perpendicular to its lengthwise edge to receive stakes 32, which in turn are used to secure the system to the ground.

While in the above embodiment the silt fence/pocket/apron is formed from a single piece of fabric, it is not required, and in fact such will not be the case where it is preferred that the silt fence and/or the apron be formed from geotextile materials different from that used to form the filter sleeve. In these circumstances, both the silt fence and apron portions of the erosion control roll can be formed of separate pieces and stitched together. The dimensions for the patterning of the various fabric pieces, seams and pockets will be obvious to those of ordinary skill in the art, and as such, the exact dimensional characteristics of the apparatus does not constitute a part of this invention.

An installation of the erosion control roll of the invention incorporating the use of both an apron and silt fence is illustrated in FIG. 3. In this illustration, the perforated pipe is shown positioned on a hillside, the apron secured to ground upstream of the filter sleeve using nails 27 (or staples, if desired). The silt fence is erected using stakes 32, which typically are made from wood. In this arrangement, silt and water will flow over apron 14, where water will pass through filter member 12 to enter the interior of pipe 10. Silt and other debris will be retained by filter sleeve 12, and behind silt fence 28, such sediment and debris eventually building up behind the fence and overtop the perforated pipe. If desired, in order to provide further stability to the installed assembly, upon installation, the apron can be covered with a limited amount of dirt, which helps hold the roll in place. When the rolls are employed in combination with and abutted by a stand alone silt fence, the stakes securing the fence add further stability to the erosion control roll installation.

In either of the above embodiments, one or both of the open ends of the core members can include couplers or connectors for connecting one core member to one or two complimentary core members. A multiplicity of core members may be connected together to create any desired length of roll/silt fence. The connectors can be standard industry connectors or couplers for coupling piping, such that each of the connected pipes is in fluid communication with each other pipe. In addition, the couplings can comprise tee connectors, or elbow connectors. In turn, the tee or elbow connectors can be connected to outlet pipes to direct fluid flow received by the core members to desired locations downstream of the core members. In cases where erosion control rolls are placed at the toe of a slope, water may be directed down a single row of core members (deployed perpendicular to the slope) to a single outlet point. Connectors fitted with outlet pipes are preferably used where it is desirable to have water redirected so as to continue downhill (parallel to the slope) following filtration.

The flexible pipe may comprise a corrugated pipe, with ribs extending along at least a portion of the exterior surface of the core member. With reference to FIGS. 4A and 4B, in one embodiment, ribs 36 and valleys 37 extend along the periphery (i.e. perpendicular to the longitudinal axis of the member) of the exterior of core member 35. One or more openings 38 can be situated in one or more of the ribs. Preferably the openings are elongated slots located across the top of the rib.

In one embodiment a plurality of the openings are located in the ribs at spaced intervals along the periphery of the core member. For example, illustrated in FIG. 4B, the openings can be spaced from a first opening along the periphery of the member within a 180 degree arc as measured from the longitudinal axis of the core member. A particularly preferred pattern is to space four openings from a first opening at positions of approximately 22.5 degrees, 45 degrees, 90 degrees and 112.5 degrees from the first opening as measured along an arc from the longitudinal axis of the core member. In practice, the first opening is situated in the rib near the top of the core member (as it will be positioned in the particular erosion control barrier) such that the additional openings will be situated towards the upstream side of the fluid flow path.

In providing such an arrangement of openings, a non-porous or closed-wall trough or channel is provided at the base of the elongate core member, below the lowest positioned opening 38. Water entering through the openings will be collected in and carried by this channel to one or both ends of the roll, depending upon the elevation of the first and second open ends. In one embodiment, as previously noted, where the roll is connected to a second roll via a tee connector, the collected water may be discharged through a pipe fitted to the connector to a point downstream of the roll. In another embodiment, the connector may direct the received water to the next downstream roll, connected in series to the first roll, for discharge at the free end of the second roll. Alternatively, an elbow connector can be provided at the free end of the second segment, and a drain pipe connected to the elbow connector to redirect the received runoff to a discharge point downstream of the erosion control roll.

In one embodiment, as illustrated in FIG. 5, at least one cable or string 34, as a tag line, may be attached to the outer filter member 12 to allow an installer to grip and tow the filter member over a separate core member to facilitate integration of the filter sleeve and core member in the field. In another variation, where the core member is to be pulled through the filter sleeve (as opposed to the sleeve being pulled over the core member) for on site installation, at the time of fabrication of the sleeve when the pocket is sewn, a loose string or tag line is laid inside the pocket along the length of the sleeve. The string may be free at one end or include a grip or handle, and contain a clasping means or noose at its other end for attachment to the end of a core member. For assembly, the one end of the line containing the clasping means is affixed to the leading end of a core member to be inserted into the sleeve. An installer then, grasping the other end of the tag line, can pull the member into the sleeve.

In another embodiment, a pipe with openings around its circumference may be used in combination with a less pervious backing member 33 (FIG. 5) affixed to the filter member. This backing member may be a solid sheet or a sheet of less pervious, finer mesh fabric, placed around the back side (downhill side) of the core member to decrease or block flow from passing transversely through the core member. By use of such a backing member, a trough for directing fluid flow is defined, whereby fluid received and retained within the core member can be redirected to one or both of its open ends for discharge. In this alternative, it should be appreciated that the corrugated pipe may be replaced by an open wire mesh or other similar frame, which defines an interior space when covered by the filter sleeve.

Defined holes are added along the apron edges both adjacent to and furthest from the main body to allow for staking. These holes may be set out in any of a number of suitable configurations to allow for more secure attachment of the apron to the ground surface.

Expendable (i.e. dissolvable) agents used to assist in the sediment removal function of the device, such as coagulants and flocculants, may be added to the inside of the elongate core member to provide a passive dosing mechanism. These agents 35, as illustrated in FIG. 3, may be in solid form, comprising their own structure, or contained in a filter bag element, or may be in liquid form contained in a smaller dosing structure.

If desired, for certain other applications, such as the formation of break waters, the erosion control roll can be capped at either end to close off the pipe. In one embodiment, the filter sleeve can be cinched closed to affect this closing off. This can be accomplished by constructing the sleeve so that it extends a significant distanced beyond the end of the core member at each end, and includes means at its ends to provide for closure. Such means can include a series of holes provided around the periphery of the ends of the sleeve, through which a cord can be threaded and then cinched to affect the closing.

Referring now to FIG. 6, in yet another embodiment of the present invention, a bypass strip 13 comprises a portion of the filter member sleeve 12 surrounding the core member 10. The opening size of the bypass strip is generally at least 16 mesh and not greater than ¼″. The material comprising the downstream half of the filter member may be less permeable (or impermeable) than that comprising the upstream half when the device is intended to reduce free runoff by intercepting and redirecting some portion of flow entering perpendicular to it. The downstream half of the pervious filter member is generally at least as permeable as the upstream half when the device is employed as a check dam to slow runoff and increase sedimentation. In providing a strip of material having a different porosity than the remainder of the material in the filter member, it is possible to govern the functions of the erosion control roll depending on the conditions immediately surrounding the roll when in use. For instance, if it is desired to strongly filter runoff for sediment and toxin, a fine mesh material may be provided in the lower portion of the filter member. But if water buildup becomes so extensive that the potential for damage from erosion is imminent, then material having a significantly greater porosity can be provided in the upper portions of the filter member. Thus, when water builds up to an undesirable height alongside the erosion roll, it is allowed to more readily pass through the filter member for diversion by the core member. Alternatively, when water diversion is a primary concern for rapid runoff, some predetermined length of erosion rolls, typically connected end to end, may be provided with a filter member having substantially impermeable lower portion, thus directing water downhill before allowing it to pass through the filter member and into the core member.

Having fully described several embodiments of the present invention, many other equivalents and alternative embodiments will be apparent to those skilled in the art. These and other equivalents and alternatives are intended to be included within the scope of the present invention. Therefore, the above description and illustrations should not be construed as limiting the scope of the invention, which is defined by the appended claims.

Claims

1. An erosion control roll comprising:

an elongate core member defining an interior space, being open at both ends, and having openings along its length;

a pervious filter member having an upstream side and a downstream side, open at both said upstream and down stream sides, and surrounding said elongate core member; and,

an apron disposed on said upstream side of said pervious filter member, said apron running the length of said filter member, and extending a predetermined distance therefrom.

2. The erosion control roll of claim 1 wherein said apron is integrally formed with said pervious filter member.

3. The erosion control roll of claim 1 where the open ends of the pervious filter member extend beyond the ends of the elongate core member.

4. The erosion control roll of claim 1 wherein the elongate core member is formed for from flexible corrugated pipe.

5. The erosion control roll of claim 1 wherein the elongate core member is formed for from an open wire mesh or other open frame material.

6. (canceled)

7. The erosion control roll of claim 4, wherein the perforations are formed in the pipe, along a 180 degree arc, the first perforation arcuately spaced from the bottom of the pipe so as to define a closed-wall trough for carrying fluid to an open end of the corrugated pipe.

8. The erosion control roll of claim 1 wherein the filter member and apron comprise a pervious geotextile fabric.

9. The erosion control roll of claim 1 further including a silt fence portion, said silt fence portion comprising a rectangular section of geotextile material, extending from the base of the core member and running longitudinally along the length of said core member, said rectangular section having a plurality of sleeves affixed to and extending perpendicularly from the leading edge of said rectangular section, said sleeves sized to receive stakes for deploying the fence and securing it in place.

10. The erosion control roll of claim 9 wherein the silt fence portion is integrally formed from a geotextile fabric.

11. The erosion control roll of claim 10 wherein the silt fence portion is formed of the same geotextile fabric as said apron and filter members.

12. The erosion control roll of claim 1 further including one or more agents interior of the core member.

13. The erosion control roll of claim 12 wherein said one or more agents interior the core member provide a passive dosing mechanism.

14. The erosion control roll of claim 1 wherein the openings in the wall of the elongate core member are spaced a distance from the base of the member, to define a walled trough for carrying fluids entering the core member to a discharge point at an end of the member.

15. An erosion control device including a plurality of the erosion control rolls of claim 2, interconnected one to the other in series by intervening couplers, thereby defining a continuous fluid path extending from one core member to the other.

16. The erosion control device of claim 15 wherein at least one of the intervening couplers is a tee coupler, said tee coupler connected to a drain pipe for directing discharge of collected fluid downstream of the roll.