Shoreline Sand Protection System and Method

This application is a continuation of International Application No. PCT/US2024/011133 filed Jan. 11, 2024, which claims priority to U.S. provisional application No. 63/438,693 filed Jan. 12, 2023, the disclosure of each of which is incorporated herein by reference in its entirety herein.

Shoreline sand dunes provide coastal protection against waves and storm surge, and also provide important ecological habitat. Usually, natural dunes are dynamic in nature and are influenced by environmental factors, and do not protect seasonal beach fluctuations and long-term erosion. Therefore, preserving or protecting sand dunes need to consider such factors. In areas with high degree of dune erosion, it is especially important to preserve dunes to protect beach property.

Fencing is often used for protecting sand dunes, but it can be easily damaged in a storm event. It may also restrict habitat for wildlife. Planting vegetation is another way to manage dunes, but seeds can be easily blown away by winds, and planting of nurseries in the sand dunes can often be unsuccessful due to the movement of the dunes themselves.

In one aspect of the present disclosure, a system suitable for protecting shoreline or other target area/zone is provided. For example, the system can help preserve sand dunes and dune cores. The system includes a geotextile sheet having an upper edge and a lower edge, the upper edge including a first channel through which a first draw cord is threaded, and the lower edge including a second channel through which a second draw cord is threaded. A flap has a lower portion affixed to the geotextile sheet proximal to its lower edge. The flap can further include un upper portion affixed to the geotextile sheet proximal to its upper edge, where the flap and the geotextile sheet form an enclosure. At least one first anchor rope can be coupled with the first draw cord on a first end and a first anchor on a second end, and at least one second anchor rope can be coupled with the second draw cord on a first end and a second anchor on a second end. The at least one first anchor rope can include a plurality of first anchor ropes (each of them having a coupled first anchor). The at least one second anchor rope can include a plurality of second anchor ropes (each of them having a coupled second anchor).

The geotextile sheet is generally porous or permeable and can be formed of a knitted polyethylene material. In some embodiments, the geotextile sheet can be formed of a biodegradable polymer material. The flap can be formed of a fabric material or mesh material, and can be made of the same material as the geotextile sheet or different material.

The upper portion of the flap can be removably affixed to an inner side the geotextile sheet, e.g., by pins or other tools that can easily puncture through fabric. The lower portion of the flap may be likewise removably affixed to an inner side of the geotextile sheet, or permanently affixed to an inner side of the geotextile sheet, e.g., by sewing or heat welding or other commonly known techniques for fusing or integrating fabric or polymeric materials.

The enclosure formed by the flap and the geotextile sheet can enclose a filling material, such as any suitable organic and/or inorganic materials, such as sand, rocks, and other materials safe for the beach. The filling material can further include seeds of plants suitable for growing at shorelines. In some embodiments, openings can be created on the top portion of the geotextile sheet for plants to grow through.

A bottom portion of the geotextile sheet can be configured to form a protrusion which can be keyed into existing beach surface to protect against undermining of the enclosure.

In some embodiments, the flap can be installed against a step of an existing stable subgrade of the shoreline. In some embodiments, the first anchor can be driven into ground underneath the enclosure such that the first anchor rope is substantially vertical. In some embodiments, the second anchor can be driven into a side of the stable subgrade of the shoreline such that the second anchor rope is substantially horizontal.

In another aspect, a method of installing a shoreline sand protection system as described herein is provided. The method includes: filling a filling material into a void formed by the geotextile and the flap; coupling an upper portion of the flap against a portion of the geotextile sheet proximal the upper edge, thereby forming an enclosure enclosing the filling material; and driving the at least one first anchor and the at least one second anchor into a stable subgrade of the shoreline.

Referring to-, which show schematic diagrams of a shoreline sand protection systemaccording to embodiments of the present invention installed at a shoreline. The system includes a geotextile sheethaving an upper edgeand a lower edge, the upper edgeincluding a first channelthrough which a first draw cordis threaded, the lower edgeincluding a second channelthrough which a second draw cordis threaded. The system also includes flaphaving un upper portionaffixed to the geotextile sheet proximalto its upper edge, and a lower portionaffixed to the geotextile sheetproximal to its lower edge, wherein the flapand the geotextile sheettogether form an enclosure. In the system, at least one first anchor ropecoupled with the first draw cordon a first end and a first anchoron a second end; and at least one second anchor ropecoupled with the second draw cordon a first end and a second anchoron a second end. The first and second channel can include openings (e.g.,) which expose sections of draw cord(or) for coupling with the anchor rope/.

The geotextile sheet is generally a porous or permeable sheet. It can be formed of a woven or knitted material, e.g., a knitted polyethylene material. In some embodiments, it can be formed of a biodegradable polymer material.

The flap can be formed of a fabric material or mesh material, and can be made of the same material as the geotextile sheet or different material.

The upper portion of the flapcan be removably affixed to an inner side the geotextile sheet, e.g., by pins or other tools that can easily puncture through fabric. The lower portionof the flap may be likewise removably affixed to an inner side of the geotextile sheet, or permanently affixed to an inner side of the geotextile sheet, e.g., by sewing or heat welding or other commonly known techniques for fusing or integrating fabric or polymeric materials.

The enclosure formed by the flap and the geotextile sheet can enclose a filling material, such as any suitable organic and/or inorganic materials, e.g., sand, rocks, and other materials safe for the beach. The filling material can further include seeds of plants suitable for growing at shorelines. In some embodiments, openings can be created on the top portion of the geotextile sheet for plants to grow through.

A bottom portion of the geotextile sheet can be configured to form a protrusion (shown in) which can be keyed into a beach surface to protect against undermining of the protection system. The protrusion can be filled with small rocks and sand.

In some embodiments, the flap can be installed against a step of an existing stable subgrade of the shoreline.

In some embodiments, the first anchorcan be driven into ground underneath the enclosure such that the first anchor ropeis substantially vertical. In some embodiments, the second anchorcan be driven into a side of the stable subgrade of the shoreline such that the second anchor ropeis substantially horizontal.

The draw cords and anchor ropes as used herein can be made from synthetic engineering plastics (such as Nylon 6 or Nylon 66), metal wires, etc. The anchors can be earth anchors made from wood, metal, plastics or other sturdy materials suitable for anchoring in soil or other ground material.

In another aspect, a method of installing a protection system as described herein is provided. A filling material is filled into a void formed by a geotextile sheet and a flap joined at a bottom portion with the geotextile sheet, an upper portion of the flap is then coupled against a portion of the geotextile sheet proximal to its upper edge, thereby forming an enclosure enclosing the filling material. The at least one first anchor and the at least one second anchor are driven into a stable subgrade of the target zone for protection, e.g., a stable subgrade of a shoreline, to tighten the enclosure and secure the enclosure to the stable subgrade. After the protection system is installed, the enclosure can be covered with backfilled sand, or other covering materials as appropriate.

While the embodiments of the present invention have been described in connection with shoreline sand protection/stabilization, it is understood that the system is also suitable for providing a surface or subsurface zone of armored protection in an upland environment for purpose of protecting a zone or structure from destructive forces of erosion. It will be readily understood to those skilled in the art that various other changes in the details, material, and arrangements of the system, structure and methods described and illustrated herein in order to explain the nature of this invention may be made without departing from the principles and scope of the invention as expressed in the appended claims.