Wave Energy Reduction System

Abstract

A method and apparatus for creating moderately quiescent water in which salt marsh wetland grasses can endure and eventually establish without the need for the total elimination of the energy of occurring waves or the restriction of sediment passage

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part (CIP) of U.S. application Ser. No. 14/568,418, filed on Dec. 12, 2014, which is a continuation-in-part (CIP) of and claims the benefit of U.S. application Ser. No. 13/847,342, filed on Mar. 19, 2013, which claims the benefit of U.S. Provisional Application No. 61/614,455, filed Mar. 22, 2012, wherein all of these priority applications are incorporated herein by reference in their entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

The present invention relates generally to a wave energy reduction method and apparatus for creating moderately quiescent water in which planted emergent salt marsh wetland grasses can endure and eventually become established. To this end, the present invention reduces wave energy without completely eliminating it while allowing the passage of soil and sediment through the apparatus to buttress the root structures of the emergent salt marsh wetland grasses.

Spartina alterniflora is a perennial deciduous grass that is found in intertidal wetlands, particularly estuarine salt marshes. S. alterniflora is the primary emergent salt marsh wetlands grass in many parts of the United States. S. alterniflora is an emergent grass growing out of the water at the seaward edge of beaches with low wave energy. Ninety percent of its biomass is believed to be underground; as such, S. alterniflora naturally accumulates sediment. Over time, this gradual accumulation of sediment builds the level of the land at the seaward edge of the salt marsh, thereby combating shoreline erosion. S. alterniflora is only one of numerous species of grasses that can be found in intertidal wetlands throughout the world; all of these grasses play an important role in stabilizing shorelines and providing buffers against storm surges and general erosion.

In many coastal locations where S. alterniflora and other salt marsh wetland grasses once existed, excessive wave energy in coastal waters due to conditions such as increased boating traffic and the creation of deeper channels makes it difficult, if not impossible, for such grasses to be reestablished on their own without reducing wave energy. Attempts to establish salt marsh wetland grasses along the shoreline without wave reduction typically result in mechanical damage to the plant leaves and, ultimately death to the plant itself. As a result, the failure to reestablish salt marsh wetland grasses compounds the problem of shoreline erosion.

Several solutions currently exist for preventing shoreline erosion, but these methods hardly address the issue of reestablishing emergent salt marsh wetland grasses. Instead, these solutions tend to focus upon protecting the ground itself.

One solution is to utilize barriers, such as concrete, rocks or other non-porous objects, by placing them between the coastal waters and the reestablishing emergent salt marsh wetland grasses to block wave energy. Such barriers are expensive to purchase, difficult to place, and difficult to remove. Concrete is heavy, and as such, the time and manpower to add these barriers can be prodigious.

Another solution is to place biodegradable fiber logs comprising a quantity of loose fibers retained in a tubular casing end-to-end on the shoreline between the coastal waters and the salt marsh wetland grasses. One example of this solution is taught by Spangler et al. (U.S. Pat. No. 6,547,493). This solution, while capable of abating wave energy, creates the costly step of packing fibers into the tubular casing. Furthermore, such fiber logs are difficult, if not impossible, to reuse since they are biodegradable. Beyond this, the logs restrict the accumulation of sediment around the salt-marsh wetland grasses, thereby undermining the very stability of these grasses. As such, they do not aid in the establishment of emergent salt marsh wetland grasses.

Mikell (U.S. Pat. Nos. 6,422,787 and 6,464,428) teaches two methods and apparatuses in which packed carpet fibers are formed into a body member, with said body member being rolled up into the form of a synthetic hay bale. The synthetic hay bale, in turn, is fastened to the ground in a water flow path. Although these methods and apparatuses would slow the flow of water, thereby reducing wave energy, like the Spangler apparatus, they would also restrict the flow of sediment to the salt-marsh wetlands grasses, thereby undermining the stability of these grasses.

A number of other solutions involve the use of tubing formed from geotextiles. However, these have several disadvantages. Most require the inclusion of some type of fill material, making them relatively complex to construct and often impractical for installation and removal by limited numbers of personnel. Also, the use of fill material will necessarily limit the amount of sediment allowed to pass through the barriers, which in turn will compromise the establishment of emergent salt marsh wetland grasses.

The flow of sediment-filled water in a reduced wave energy environment is necessary for emergent salt marsh wetland grasses to become established. As water with sediment passes over the grasses, the sediment is deposited around the grasses, strengthening the support structure for the grasses. Unlike other inventions, the present invention helps to break the speed of the water across the grasses to allow sediment to be deposited more readily.

Theisen (U.S. Pat. No. 7,883,291) teaches a process/apparatus wherein a mat of natural fibers is wound in the form of a log to form fiber filtration tubes. The Theisen process/apparatus further employs a flocculating agent to flocculate fine particles, thereby accomplishing a high-degree of sediment control. In sharp contrast, the present invention uses no flocculating agent since the flocculation of sediment particles within the apparatus would prevent sediment from accumulating around emergent salt marsh wetland grasses. The accumulation of sediment particles around emergent salt marsh wetland grasses is essential for the long-term stability of these plants. Therefore by incorporating the use of a flocculant, the Theisen process/apparatus would compromise the establishment of emergent salt marsh wetland grasses, which is the stated purpose of this invention.

While Myrowich (U.S. App. 2009/0020639) teaches a rolled erosion control blanket, and a process for manufacturing such a blanket, this process is directed to optimizing the ability of such a blanket to be rolled up for transportation purposes. It envisions the unrolling of the blankets at the work site. This shares the same problem as the teaching of Carpenter (U.S. Pat. No. 7,695,219), viz: a blanket placed flat on the ground is largely useless for protecting salt marsh wetland grasses from wave energy.

It would be desirable to have a method and/or apparatus that will enable emergent salt marsh wetland grasses to establish and grow without totally eliminating the energy of occurring waves or blocking the flow of sediment-rich water across the grasses. Furthermore, it would also be desirable to have a method and/or apparatus that are inexpensive to utilize. Still further, it would be desirable to have a method and/or apparatus that are simple to relocate and reuse. Therefore, there currently exists a need in the industry for an inexpensive method and/or apparatus that can (A) protect emergent salt marsh wetland grasses from excessive wave energy while concomitantly allowing sediment to deposit onto these grasses, and (B) be relocated to other shores for reuse when these grasses become stable enough to withstand incoming wave energy.

BRIEF SUMMARY OF THE INVENTION

The present invention advantageously fills the aforementioned deficiencies by providing a wave energy reduction method and apparatus in which emergent salt marsh wetland grasses located between the wave energy reduction apparatus and the shoreline can endure and eventually establish without the need for the total elimination of the energy of occurring waves or the restriction of sediment passage.

Highly-porous geotextile materials (such as, but not limited to, ENKAMAT fabric, which is known to have a porosity of at least 95%) are assembled into rolls. These rolls are bound with cable ties, preferably ties that can withstand ultraviolet light, to maintain their cylindrical shape. The rolls are placed out into water that is at least 12-14 inches (30-36 cm) deep on the soil end to end without space between them, forming a line of geotextile material rolls.

Multiple anchors, preferably comprised of steel, are then placed into the soil on one side of the line of rolls, preferably on that side closest to the shoreline. These anchors are referred to throughout this specification as “steel anchors.” However, the use of the word steel or any other description thereto should not be deemed as limiting the composition of the anchors to any one type of material.

Multiple strands of rope, preferably comprised of polypropylene, are inserted into multiple layers of tubing, preferably polyethylene tubing. Each rope-and-tubing combination is inserted, yet again, into another layer of tubing, preferably polyethylene tubing, to form multiple “rope ties.”

Each rope tie is then looped through a unique anchor and underneath the line of rolls to form the shape roughly similar to that of the letter “U” such that both ends of each rope tie are pointing straight up. The ends of each rope tie are then tied together, thereby securing the line of rolls to the anchors.

Although the preferred embodiment for this invention utilizes polypropylene rope combined with polyethylene tubing, the invention may use any type of rope, with or without polyethylene tubing. Likewise, the invention may use any type of tubing to cover the rope, regardless of whether the same is made of polyethylene, or no tubing at all. Furthermore, the invention may use any type of cable ties, whether or not they can resist ultraviolet light. Still further, the invention may use any type of anchor, regardless of its composition.

This method and/or apparatus reduce the size and force of incoming waves as the waves pass through the line of geotextile material rolls. As a result, moderately quiescent water is created whereby salt marsh wetland grasses can be established and endure. After these grasses have been established, the user may then remove the rolls of geotextile material, along with the steel anchors and the rope ties, and place them elsewhere.

This invention is functionally different from other solutions because it attempts to abate wave energy, not eliminate it altogether. Research has shown plant stems and trunks are stronger when subjected to some movement caused by wind and waves. Moreover, by allowing water to pass through the wave energy reduction barrier, sediment returning from the coastal waters is not inhibited from accumulating around the emergent salt marsh wetland grasses, further aiding in the prevention of shoreline erosion.

This invention is structurally different from other solutions because it comprises materials that are readily accessible and cost-effective to utilize. These lightweight materials are easy to transport and are inexpensive to obtain. As such, it only takes one person a short time to install, and later remove, a wave energy reduction system.

Among other things, it is an object of the present invention to protect emergent salt marsh wetland grasses from wave energy without incurring any of the problems or deficiencies associated with prior solutions.

The present invention now will be described more fully hereinafter with reference to the accompanying drawings, which are intended to be read in conjunction with both this summary, the detailed description and any preferred and/or particular embodiments specifically discussed or otherwise disclosed. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of illustration only and so that this disclosure will be thorough, complete and will fully convey the full scope of the invention to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of the preferred embodiment of the apparatus.

FIG. 2 shows a cross section view of the preferred embodiment of the apparatus, particularly depicting the attachment to the anchor.

DETAILED DESCRIPTION OF THE INVENTION

The preferred embodiment of the invention is described as follows:

To create the wave energy reduction system 10, assemble 8-feet-by-27 feet (2.44 m×8.2 m) of geotextile fabric having a porosity of at least 95% and no flocculant into a cylindrical roll that is 12-14 inches (30-36 cm) in diameter and 8 feet (2.44 m) in length. The roll is tied together with black cable ties 11 to maintain the cylindrical shape of the roll. Tie the roll together with 48-inch (1.22 m) long and ¼-inch (6.35 mm) wide black cable ties. The black cable ties should have ultraviolet light inhibitors and a 175 psi (1.21 MPa) tensile stress rating. Locate the two end-of-the-roll cable ties 12 inches (30.5 cm) from each end of the roll. Evenly space the remaining cable ties 18 inches (45.72 cm) apart along the roll. Cable ties will be pulled tightly against the geotextile fabric to secure the material into a rolled form.

When setting the wave reduction system in position, place them in water that is at least 12-14 inches (30-36 cm) deep, on the soil, so the exposed cut edge is beneath the roll and facing toward the mainland. This will protect against the possibility of wave action forces opening up the roll.

Steel anchors 12 secured into the soil serve as the method for holding the wave energy reduction system in place. Install the ½-inch (12.7 mm) diameter steel anchors with tensile strength of 1400 psi (9.65 MPa) into the soil to the point where the eye of the anchor is just above the soil level. Use three 30-inch (76 cm) long anchors for each 8-foot (2.4 m) long roll. Locate the anchors 24 inches (61 cm) from each end of the roll and the third anchor at the center of the roll.

Two sizes of black polyethylene tubing and polypropylene rope are the fastening elements for attaching the wave energy reduction system to the earth anchors. Together these materials create a technology that has proven effective in establishing emergent marsh grasses.

Attach the roll to each anchor with a 6-foot (1.8 m) long piece of ½-inch (12.7 mm) polypropylene rope 13 threaded into the polyethylene tubing as further described herein. The rope will have a tensile stress of 425 pounds per square inch (2.93 MPa). The ends of the rope will be heat treated to resist fraying and becoming unraveled. Thread the 6-foot long piece of rope through a 24-inch (61 cm) long section of 0.62 ID×0.71 OD inch (15.7 ID×18.0 OD mm) polyethylene tubing 14. Thread the aforementioned tubing into a 21-inch (53 cm) section of 83 ID×0.92 OD inch (21.1 ID×23.4 OD mm) tubing 15. The combined tubing layers protect the polypropylene rope from abrasion against the steel anchor eyelet. Thread the rope and tubing combination through the eyelet and around the wave energy reduction system. Position the polyethylene tubing in a rough “U” shape around the roll with the “U” pointing upward. The tubing will extend approximately half way up the sides of the roll, and the rope will extend to a point above the roll where it can be pulled tightly and tied. When tying the rope together, pull the rope ends tightly against the top of the roll and secure the rope to the wave reduction system with 6-8 overhand knots. Secure each knot tightly before tying the next knot.

The best mode for utilizing the invention is described as follows:

It is recommended that the invention be used to protect emergent salt marsh wetland grasses by placing the wave energy reduction system out into water that is at least 12-14 inches (30-36 cm) deep as described in the preferred embodiment above. It is further recommended that multiple systems be placed end-to-end, as needed, to protect greater areas of emergent salt marsh wetland grasses.

The drawings are further described as follows:

Referring to the figures, FIG. 1 shows the preferred embodiment of the wave energy reduction system. Notice how the roll 10, being comprised of geotextile material having a porosity of at least 95% (preferably ENKAMAT material), is rolled such that the exposed edge of the roll is pointed to the shoreline and away from the incoming waves. The cylindrical shape of the roll is maintained by cable ties 11 that are wrapped and tied around the roll.

In the preferred embodiment, five cable ties are spaced along the roll with the third cable tie being located at the center. Further notice the anchors 12 that are spaced along the side of the roll. Further notice that rope ties 13 are looped through the anchors and under the rolls. Further notice that these rope ties are tied at the top of the roll, thereby securing the roll to the soil.

FIG. 2 shows the cross-section view of the preferred embodiment of the apparatus 10. Notice that the cross-section is cut where a rope tie 13 is looped through a steel anchor. Further notice that the preferred embodiment uses a rope tie mechanism that comprises a rope, which is fed through a 24-inch (61 cm) length of polyethylene tube 14, which is further fed through a 21-inch (53 cm) length of a larger-diameter polyethylene tube 15. The ends of the rope are tied together at the top of the wave energy reduction system. The multiple layers of polyethylene tubing serve to insulate the rope from fraying the geotextile mat. Please note that the polyethylene tubing is optional, and as such, the specification is understood to describe the apparatus without the tubing.

While the present invention has been described above in terms of specific embodiments, it is to be understood that the invention is not limited to these disclosed embodiments. Upon reading the teachings of this disclosure many modifications and other embodiments of the invention will come to mind of those skilled in the art to which this invention pertains, and which are intended to be and are covered by both this disclosure and the appended claims. It is indeed intended that the scope of the invention should be determined by proper interpretation and construction of the appended claims and their legal equivalents, as understood by those of skill in the art relying upon the disclosure in this specification and the attached drawings.

Claims

1. A wave energy reduction system comprising a geotextile mat, said geotextile mat being rolled into a roughly cylindrical shape and secured to the ground in the water near a shoreline.

2. The wave energy reduction system of claim 1, in which the geotextile mat is substantially devoid of a flocculant.

3. The wave energy reduction system as in either claim 1 or claim 2, in which the geotextile mat has a porosity of at least 95%.

4. The wave energy reduction system as in any one of the preceding claims, further comprising multiple cable ties, said cable ties being wrapped and tied around the circumference of the rolled geotextile mat to maintain the cylindrical shape thereof.

5. The wave energy reduction system as in any one of the preceding claims, further comprising multiple anchors, said anchors being attached to the ground along the rolled geotextile mat.

6. The wave energy reduction system of claim 5 further comprising multiple pieces of rope equal to the number of anchors in use.

7. The energy reduction system of claim 6 further comprising pieces of flexible tubing equal to the number of pieces of rope being used, each piece of said rope being threaded through a corresponding piece of said flexible tubing to form a primary rope-and-tubing combination.

8. The wave energy reduction system of claim 7 further comprising pieces of flexible tubing equal to the number of primary rope-and tubing combinations in use, each primary rope-and-tubing combination being threaded through a corresponding piece of said flexible tubing to form a secondary rope-and-tubing combination.

9. The wave energy reduction system of claim 8, in which each secondary rope-and-tubing combination is wrapped around the circumference of the rolled geotextile mat and tied to an adjacent anchor.

10. The wave energy reduction system of claim 9, in which each rope is wrapped around the circumference of the rolled geotextile mat and tied to an adjacent anchor.

11. A wave energy reduction apparatus comprising:

(a) a geotextile mat that is rolled into a roughly cylindrical shape;

(b) a multiplicity of cable ties that are wrapped and tied around the circumference of the rolled geotextile mat to maintain the cylindrical shape thereof;

(c) a multiplicity of anchors that are attached to the ground along the rolled geotextile mat; and

(d) a number of pieces of rope equal to the number of anchors used, each piece of rope being wrapped around the roll, inserted through the eyelets of the anchors, and securely tied at the top of the roll.

12. The wave energy reduction apparatus of claim 11, in which the geotextile mat is substantially devoid of a flocculant.

13. The wave energy reduction apparatus as in either claim 11 or claim 12, in which the geotextile mat has a porosity of at least 95%.