DeBordieu Beach Renouishment Update 5/8/15
DeBordieu’s Beach Restoration project is complete!
All of the pipes have been removed from the beach and a crew will begin installing the remaining sand fences this week. The dune vegetation planting is scheduled for May 12.
The DeBordieu Colony Community Association and DeBordieu Club Boards invite all DeBordieu Owners to join in a ribbon cutting ceremony to celebrate the summer season at the Blue Heron walkway on Friday, May 22, 2015 at 5:00 PM.
DeBordieu Beach Renouishment Update 4/27/15
The DeBordieu beach restoration project is progressing quickly now!
Approximately 6,000 ft. of the beach and dune have been completed from the south end of the property up to the Beach Club. With the rapid production rates and good weather, Marinex hopes to complete the remaining 2,000 ft. of fill placement this week.
The dune restoration project will be completed by mid-May with vegetation planting on May 12.
DeBordieu Beach Renourishment Update 4/7/15
We are pleased to report that the south end of the project was completed last week!
The taper ends at ~200 ft. south of the DeBordieu property line, although placed sand will continue to benefit this shoreline for years due to sand spreading and littoral transport. The project design maximizes protection by including a wider dune feature and via placement of sand along the central section of the beach. Our past annual monitoring surveys indicate that the mid-beach is the main "feeder beach" for adjacent areas, so a maximum volume is included in this area. This area will feed sand both to the north and south, similar to the 2006 project. Pumping has begun to the north.
DeBordieu Beach Renourishment Update 3/25/15
The DeBordieu Colony Community Association is doing a great job of keeping DeBordieu Owners apprised of the progress of the beach restoration project at this private residential community just north of Charleston, South Carolina. Here's the latest from Blanche Brown, General Manager of the DCCA:
"Slow progress continues along the south end of the beach restoration project with approximately 40,000 cubic yards left until that end is complete. Unfortunately the weather does not appear overly favorable this week.
During downtime, the crew has been busy installing sand fencing which is the first phase of the dune restoration project. After beach nourishment construction is complete, the second phase, dune vegetation planting, will begin. The state (OCRM) requires sand fencing to be installed in a V-pattern, open to the shoreline, to avoid interfering with sea turtle nesting or hatchlings. A line of V's is being installed along the newly constructed dune with openings left for public access. The sand fencing will trap windblown sand to minimize sand loss outside the project area, and to build elevation at the newly established dune crest. Native dune vegetation will be planted after construction and will further assist with sand trapping.
The goal of the dune restoration program is to establish a high, continuous dune that will serve as a buffer from storms and a future reservoir of sand if needed. Access paths are being established at each public and private dune walkover. Ideally, the paths are 1) slanted, not directly perpendicular to the shore, and 2) at the same elevation as the adjacent dune. In other words, the project aims to trap sand in the walkways and along the dune crest. We are trying to avoid "holes" in the new dune that would funnel storm surge.
Both sand fencing and dune vegetation will be installed along the entire project area. Along the north end, where a dune is already established, the project aims to fill in patchy areas behind the toe of vegetation line.
The newly established dune areas will be off limits with the exception of the access paths. The recreational beach will be established seaward of the toe of vegetation.
DeBordieu Beach Renourishment Update 3/17/15
Sand placement on DeBordieu Beach has been completed to the south end of the bulkhead, with most of the beach along the bulkhead now re-opened for use.
Today the construction zone has moved into the Ocean Green area of DeBordieu, on the south end.
Last week, the dredge shut down on Wednesday and started back up on Sunday.
The weather appears favorable for dredging until this Thursday. If all goes well this week, pumping on the south end will be complete and the pipe will be turned to the north.
The DeBordieu Colony Community Association is doing a fantastic job, as always, of keeping DeBordieu Property Owners informed about this very important project.
DeBordieu Beach Renourishment Update 2/15/15
Sand placement on DeBordieu Beach has progressed nearly to the south end of the bulkhead.
The dredge has placed 290,000 cubic yards along over 2,200 feet of beach. About 1,500 feet of completed beach has been reopened to the community.
Sand fencing installation will begin in a few weeks.
The dredge
Savannah is a 24" cutter-suction dredge, which is a floating platform (not a ship) with a rotating excavating cutterhead. This turning "corkscrew" digs loosened sediment which is sucked by pumps through a 24" pipe and pump system that transports the sand and water slurry up to typical distances of 5 miles. Engines on board the vessel power 3 massive pumps that guzzle up to 5,500 gallons of fuel per day!
It won't be long until DeBordieu Residents and guests once again have access to the full 6 and a half miles of beach on DeBidue Island!
DeBordieu Beach Renourishment Update 2/2/15
Thank you Blanche Brown, DeBordieu Colony Community Association General Manager, for keeping us all updated on the Beach Renourishment project at DeBordieu!
"We are happy to announce that the project made significant progress last week!
Aside from one weather day, the dredge worked continuously. Nearly 1,000 feet of beach has been completed with a total of 140,000 cubic yards placed. The crew is also placing sand by hand to create a smooth transition between the newly placed sand and the existing dune scarp.
The dredge shut down today (Monday) due to weather, but work is expected to resume when the winds and seas calm down tomorrow. Another productive week is expected until the next front comes through on Friday."
DeBordieu Beach Renourishment Update 1/26/15
"Marinex began pumping sand onto the beach on Monday January 19 at Beach Walkway #7. The progress map below illustrates that the crew is working in roughly a 500-ft-long construction zone. They placed a construction pad, which provides an area for the equipment to operate. Rough seas forced the dredge to pull in to safe harbor in Winyah Bay late in the week, but pumping resumed Sunday. Work will now begin to progress to
the south. Weather this week is anticipated to be favorable. Although winds may cause a short delay, the dredge is expected to remain in the borrow area and ride out the swell.
The nourishment material is of good quality with some shell hash mixed in with the sand. Some rock is also present, but that is common when using offshore sand borrow areas in South Carolina.
As was described last week, the beach being built by the contractor has not yet assumed its natural state. Last week, the process of profile equilibration was explained, where the beach narrows as sand is transported
offshore by wave energy and the beach takes on a more natural slope. Please note that the beach berm is being constructed higher than it was during the last renourishment to provide enhanced storm protection.
The dune is also not yet in a natural form. It is being constructed wide and flat. Sand fencing and dune vegetation will trap windblown sand on top of this constructed dune, creating a more natural sloping dune surface. The dune elevation is the same as during th
e last project, but because the beach berm elevation is higher, the dune may appear lower. As the dune fencing and vegetation trap windblown sand, the elevation will increase."
Beach Renourishment Update 1/19/15
The DeBordieu Colony Community Association published an update on the DeBordieu Beach Restoration this week:
The dredge Savannah arrived at DeBordieu on Sunday. Rough seas kept it at the dock last week. The dredge crew will begin digging material from the offshore borrow area today (Monday). Sand will be delivered to the beach through the submerged pipeline in a slurry of roughly 20% sediment and 80% water. Beach crews will redistribute the sediment with heavy equipment and then survey the new dry beach and underwater slope to ensure accurate placement.
It is important to keep in mind that beaches are similar to icebergs in that much of the beach is underwater. The beach will be constructed abnormally wide because it is well known that the beach will equilibrate soon after construction. This means that the wide beach that is constructed by the bulldozers will start to narrow immediately. Natural wave action will smooth the beach to a gentler slope, thereby causing the beach width to narrow. This process does not involve a loss of sand from the beach, rather a redistribution of sand to the near shore area and to the sand bar. 
Like the existing beach, eventually about 2/3 of the new material will be underwater, acting like the foundation of a house supporting the dry beach. Although it will appear that the beach is rapidly eroding after nourishment, this is expected and indicative of the beach transforming from a constructed, designed beach to a natural beach form.
DCCA General Manager Blanche Brown requests that everyone please stay out of the work zone and once construction starts, expect 24 hour operations when sea conditions allow.
We are all looking forward to the beach at DeBordieu returning to its renourished state!
Approximately 6,000 ft. of the beach and dune have been completed from the south end of the property up to the Beach Club. With the rapid production rates and good weather, Marinex hopes to complete the remaining 2,000 ft. of fill placement this week.
The dune restoration project will be completed by mid-May with vegetation planting on May 12.
The taper ends at ~200 ft. south of the DeBordieu property line, although placed sand will continue to benefit this shoreline for years due to sand spreading and littoral transport. The project design maximizes protection by including a wider dune feature and via placement of sand along the central section of the beach. Our past annual monitoring surveys indicate that the mid-beach is the main "feeder beach" for adjacent areas, so a maximum volume is included in this area. This area will feed sand both to the north and south, similar to the 2006 project. Pumping has begun to the north.
"Slow progress continues along the south end of the beach restoration project with approximately 40,000 cubic yards left until that end is complete. Unfortunately the weather does not appear overly favorable this week.
During downtime, the crew has been busy installing sand fencing which is the first phase of the dune restoration project. After beach nourishment construction is complete, the second phase, dune vegetation planting, will begin. The state (OCRM) requires sand fencing to be installed in a V-pattern, open to the shoreline, to avoid interfering with sea turtle nesting or hatchlings. A line of V's is being installed along the newly constructed dune with openings left for public access. The sand fencing will trap windblown sand to minimize sand loss outside the project area, and to build elevation at the newly established dune crest. Native dune vegetation will be planted after construction and will further assist with sand trapping.
The goal of the dune restoration program is to establish a high, continuous dune that will serve as a buffer from storms and a future reservoir of sand if needed. Access paths are being established at each public and private dune walkover. Ideally, the paths are 1) slanted, not directly perpendicular to the shore, and 2) at the same elevation as the adjacent dune. In other words, the project aims to trap sand in the walkways and along the dune crest. We are trying to avoid "holes" in the new dune that would funnel storm surge.
Both sand fencing and dune vegetation will be installed along the entire project area. Along the north end, where a dune is already established, the project aims to fill in patchy areas behind the toe of vegetation line.
The newly established dune areas will be off limits with the exception of the access paths. The recreational beach will be established seaward of the toe of vegetation.
Sand placement on DeBordieu Beach has been completed to the south end of the bulkhead, with most of the beach along the bulkhead now re-opened for use.
Today the construction zone has moved into the Ocean Green area of DeBordieu, on the south end.
Last week, the dredge shut down on Wednesday and started back up on Sunday.
The weather appears favorable for dredging until this Thursday. If all goes well this week, pumping on the south end will be complete and the pipe will be turned to the north.
The DeBordieu Colony Community Association is doing a fantastic job, as always, of keeping DeBordieu Property Owners informed about this very important project.
The dredge has placed 290,000 cubic yards along over 2,200 feet of beach. About 1,500 feet of completed beach has been reopened to the community.
Sand fencing installation will begin in a few weeks.
The dredge Savannah is a 24" cutter-suction dredge, which is a floating platform (not a ship) with a rotating excavating cutterhead. This turning "corkscrew" digs loosened sediment which is sucked by pumps through a 24" pipe and pump system that transports the sand and water slurry up to typical distances of 5 miles. Engines on board the vessel power 3 massive pumps that guzzle up to 5,500 gallons of fuel per day!
It won't be long until DeBordieu Residents and guests once again have access to the full 6 and a half miles of beach on DeBidue Island!
Aside from one weather day, the dredge worked continuously. Nearly 1,000 feet of beach has been completed with a total of 140,000 cubic yards placed. The crew is also placing sand by hand to create a smooth transition between the newly placed sand and the existing dune scarp.
The dredge shut down today (Monday) due to weather, but work is expected to resume when the winds and seas calm down tomorrow. Another productive week is expected until the next front comes through on Friday."
Like the existing beach, eventually about 2/3 of the new material will be underwater, acting like the foundation of a house supporting the dry beach. Although it will appear that the beach is rapidly eroding after nourishment, this is expected and indicative of the beach transforming from a constructed, designed beach to a natural beach form.
No comments:
Post a Comment