Florence Renourishment Project- PHASE III (2021)



PROJECT UPDATES
(please scroll further down for an interpretation guide and general project overview) 

2/24/2021 - LIBERTY ISLAND ARRIVED MONDAY – REPAIRS UNDERWAY – PROJECT START PLANNED FOR TOMORROW
Great Lakes Dredge & Dock’s hopper dredge, the Liberty Island arrived this Monday but has to undergo a repair (welding) while anchored at one of the Morehead City Port berths before work can commence.  The vessel Lady Paige has begun trawling the ODMDS borrow site as part of  endangered/threatened species relocation efforts to minimize any interaction with the dredge.  We anticipate dredging to start late tomorrow (2/25/2021), with the first load being delivered to Reach 1 (far western Emerald Isle) a few hours later.  With respect to the second dredge scheduled to work on the project (the Ellis Island) – while still tentative, her arrival is expected sometime on March 17th/18th.  The Ellis Island will work in tandem with the Liberty Island until the project is completed by the April 30th deadline.  Initially, we are planning for the Liberty Island to service the 1st submerged pipeline (subline) landing in Reach 1 and the 2nd subline landing in central Emerald Isle, located west of Bogue Inlet Pier (MAP).  The Ellis Island, when she arrives, will begin pumping from subline 3 and then leapfrog to subline 4 – both of which are located east of Bogue Inlet Pier (again, see MAP).  And lastly, the CRAB (amphibious survey vehicle) is being constructed and will be a prominent feature along the project landscape (SEE PHOTO – 2/23/2021).

2/17/2021 - LIBERTY ISLAND ALL SET TO ARRIVE AND LIKELY START ON FEBRUARY 21, 2021.  The hopper dredge Liberty Island is scheduled to set sail from a current job in Florida to arrive and start our Phase III Project in earnest (dredging, hauling, pumping sand) on February 21st - this upcoming Sunday.  As mentioned in previous updates, the nourishment will begin in the far west Emerald Isle Reach (REACH 1 MAP).  Sand will be pumped from the dredge through the submerged pipeline that lands near Point Emerald Villas.  The nourishment operation will work west, then east from this point until the reach is completed, and will subsequently "leapfrog" to the next reach to the east (Reach 3 - see MAP).  


2/10/2021 - SAME SCHEDULE.   NEW PLANTING, SAND FENCING, AND POST & ROPE NOTES.  NEW PSA AND SAND FENCING FACT SHEET!  

(1)  SCHEDULE - The hopper dredge Liberty Island remains on schedule to arrive and begin the project in earnest on February 20th as discussed in previous updates (see below).

(2)  DUNE PLANTSA detailed dune planting work scope is included in the dredging contract, which incorporates the planting, fertilization, and initial watering of several 100,000s of sea oats on top and mostly down the entire slope of the newly constructed dune.   The Sea Oats will be augmented with Bitter Panicum and Seashore Elder (see the DUNE BOOK; Pages 12 - 16 for a description of the plants).  The contract also stipulates the use of native plants only and to this end, the subcontractor (Earth Balance)  obtained seeds and cuttings of plants from Emerald Isle this past October and have since been germinated and are waiting in the greenhouse ready to be planted once the nourishment phase of the project is completed (see photos below).
 
 EARTH BALANCE GREENHOUSE PHOTOS - 2/9/2021
Sea Oats Bitter Panicum Seashore Elder

(3)  SAND FENCING - Have a question concerning sand fencing or installing post & rope walkways?  Then see this great, new video style Public Service Announcement from the Town of Emerald Isle and the Sand Fencing Fact Sheet above.

2/4/2021 - GETTING EVERYTHING SET FOR THE FEBRAURY 20th.  The hopper dredge Liberty Island remains on schedule to arrive and begin the parade of dredging, holding, sailing, and pumping sand on the beach on February 20th - starting in Reach 1 (far west Emerald Isle).    The Liberty Island will complete reach 1 and generally progress or "leapfrog" across reaches 3, 4, and 5 in a west to east direction - generally through central and east Emerald Isle.  As mentioned many times in the past, the second, larger capacity dredge (the Ellis Island) is expected to arrive later in the project to help complete the work - as late as April 1st but we are working diligently to see her arrival sooner.  The Liberty Island and Ellis Island are working in Florida and Charleston SC , respectively and have been feverishly been trying to compete their work at these jobs while also encountering COVID-related issues both at sea and on-land.   

1/27/2021 - 2nd SUBMERGED PIPELINE LANDING SET IN REACH 3; START DATE PUSHED BACK TO ROUGHLY FEBRUARY 20th.  This past Sunday (1/24/2021), Great Lakes Dredge & Dock took advantage of the calm seas and set the 2nd submerged pipeline just west of Bogue Inlet Pier in Reach 3 (see Station "187+50" in the Area of Detail Map).    These submerged pipelines will be "leap-frogged" west to east across the project as nourishment progresses in that general direction.  Otherwise, our start date has been pushed back to roughly February 20th.  The hopper dredge Liberty Island and Ellis Island have encountered issues at their current jobs in Florida and South Carolina, respectively causing some scheduling changes in terms of their arrival times here.   The arrival of the dredges could now nearly coincide with one another to help complete the project before the April 30th environmental window closes for the sea turtle nesting season and other biological resources.

1/20/2021 - 1st SUBMERGED PIPELINE LANDING SET IN REACH 1; FEBRUARY 12th CONTINUES TO BE THE START DATE.  The mobilization process is in full swing as equipment is being delivered to the Dog-Leg 4WD Access and perhaps more encouraging, Great Lakes Dredge & Dock (GLDD) set the 1st submerged pipeline ("subline") in Reach 1 yesterday (1/19/2021) - see map and photos below.   Sand will be pumped through this subline once the hopper dredge Liberty Island arrives as pipe will be added to the subline to pump sand west, then east from the subline landing point at the Point Emerald Villas/Lands End boundary.  Again, we are expected to dredge, hold, sail, and pump-out the first load of sand from the ODMDS borrow site on February 12th.

 PHOTOS - 1/20/2021
Subline Photo #1 Subline Photo #2 Subline Photo #3 Subline Photo #4

1/13/2021 - MOBILIZATION SCHEDULE GENERALLY THE SAME, START DATE PUSHED TO FEBRAURY 12th.  Akin to building a house from the ground up (i.e., there’s always delays), Great Lakes Dredge & Dock (GLDD) has shifted the start of the project by a couple of weeks (see 1/6/2021 update immediately below).  The hopper dredge Liberty Island is thus scheduled to start on February 12th in Reach 1 (far west Emerald Isle) rather than during the last week of January as initially planned.   While inconvenient perhaps, there is no cause for alarm – we started our Phase II project last year (2020) on February 5th with a similar amount of cubic yards (just north of 2 million cubic yards) albeit a shorter sail distances to and from the borrow sources compared to the Phase III Project.  However, GLDD is already planning to keep the second and larger capacity hopper dredge, the Ellis Island on-site for a longer period of time to meet the April 30th project completion deadline.  Otherwise, the mobilization schedule pretty much remains the same – water based equipment has started arriving on-site in the Harbor (Morehead City) and the land-based equipment should start arriving next week (again using the dog-leg” 4-WD ramp near the Emerald Isle’s Eastern Regional Access as the main entry point to and from the beach).

1/6/2021 - LOOKING TO START THE LAST WEEK OF JANUARY.   
The project sponsors (Carteret County and Emerald Isle), Engineers (Moffatt & Nichol), dredging contractor (Great Lakes Dredge & Dock), and State and federal resource agencies had our first weekly meeting earlier today for the Phase III Project.   The water-based equipment (submerged lines, tugs, ancillary vessels, etc.) should begin arriving later this week and the land-based pipe, office shacks, and “yellow steel” (bulldozers, front-end loaders, etc.) are scheduled to begin to be delivered to the site via flatbed trucks late next week.  The “dog-leg” 4-WD ramp near the Emerald Isle’s Eastern Regional Access will be the main access point for mobilizing and temporary staging this equipment.   The hopper dredge Liberty Island is scheduled to arrive and begin dredging/sailing/pumping sand somewhere in the January 24th  - 31st timeframe.  REACH 1 (far west Emerald Isle) will be nourished first (see MAP).

10/27/2020 – PRE-CONSTRUCTION MEETING, LOGISTICAL NOTES, END OF JANUARY.  
The project sponsors (Carteret County and Emerald Isle), Engineers (Moffatt & Nichol), and the dredging contractor (Great Lakes Dredge & Dock) had a pre-construction meeting earlier today with State and federal resource agencies that essentially “kicks-off” the project.   Great Lakes Dredge & Dock (GLDD) plans to mobilize land- and water-based pipe, heavy equipment, personnel, etc. starting in December and dredging/pumping is scheduled to begin in the final week of January 2021.   The "dog-leg" 4WD Ramp near the Emerald Isle Eastern Regional Access will serve as the main point to load and stage the land-based pipe.
       The dredge Liberty Island will arrive on-site first and will generally progress and “leapfrog” west to east in Central & East Emerald Isle.  At some point in mid-March the larger hopper dredge, the Ellis Island will accompany the Liberty Island and serve the Bogue Inlet Ocean Reach, and could subsequent stay on site to help complete the project before the April 30th environmental window closes for the sea turtle nesting season and other biological resources.   
       As described below, subsequent to completing a “cut” and filling the hopper, the dredge will travel and discharge (pump) sand via a buoyed interface located offshore that transitions to the pre-construction dry beach via a long submerged pipeline (or "subline").  A secondary “elbow’ connection is used to transport material in one direction (east), then the other direction (west) along the beach to complete approximately 1 - 2 mile sections as lengths of pipe are added and subsequently broken down. The pick-up line/subline/elbow assemblies are subsequently transited (leapfrogged) down the beach until the nourishment reaches have been filled.   The following maps have been updated depicting the approximate locations where the sublines will land for Central & East Emerald Isle and Bogue Inlet Ocean.


HOW TO INTERPRET THE PROGRESS MAPS
for The Post Florence Renourishment Project (Phase III)

 

Phase III of the Post Florence Renourishment Project will utilize 2,012,850 cubic yards (cy) of sand obtained from the Offshore Dredged Material Disposal Site (ODMDS) associated with Morehead City Federal Navigation Project.  The project includes four discrete reaches totaling 9.4 linear miles of beach in Emerald Isle - Bogue Inlet Ocean (166,350 cy), West Emerald Isle (708,750 cy), Central Emerald Isle (537,750 cy), and East Emerald Isle (600,000 cy) as depicted in the Project Construction Map above.  As a mental picture, a conventional dump truck holds roughly 12 cubic yards of wet sand. The project is scheduled to be conducted between January 1 to April 30, 2021 and therefore within the construction window established to limit impacts to biological resources.  The dredging contract has been awarded to Great Lakes Dredge & Dock and the ocean-certified, self-contained hopper dredges Liberty Island and Ellis Island will be employed for the project - similar to the Phase I and Phase II efforts in 2019 and 2020, respectively.  

 

Hopper dredges utilize dragheads affixed to trailing-arm suction pipes mounted on both sides of the vessel (port and starboard). The dragheads loosen the sand on the bottom off the seafloor and deliver the material to the vessel’s “belly” via the suction arms. Subsequent to completing a “cut” and filling the hopper, the dredge will travel and discharge (pump) sand via a buoyed apparatus located offshore that connects to a submerged pipeline extending to the pre-construction dry beach.  A secondary, land-based discharge pipe is used to transport material in one direction (east or west), then the other direction along the beach to complete approximately 1 - 2 mile sections as lengths of pipe are added and subsequently broken down. The buoyed apparatus/submerged pipeline assembly assembly is subsequently transited down the beach until the nourishment reaches have been filled. Dredged sand is bulldozed into general construction specifications for subsequent grading into final contours, possibly tilled, and opened for recreational use.  The dredges Liberty Island has a maximum capacity of 6,540 cy and the Ellis Island 14,800 cy under optimal conditions.

 

Project engineers use “stations” positioned along the beach to monitor construction progress and to verify in-place volumes of sand pumped on the beach by dredging contractors. The progress maps above provide detailed views of the Post Florence Renourishment Project (Phase III) reaches to be completed in 2021 with the location/identification of the station numbers and the location of the submerged pipeline positions. buoyed pipelines. The shaded areas in red represent the completed portions of the project and will be updated on a weekly basis (at least) throughout construction.

The station numbers included in the progress maps conveniently correspond to thousands of linear feet along the beach. For instance, the distance between station “197+00” (Bogue Inlet Pier) and “224+00” (Black Skimmer Ramp) in the Area of Detail graphic above is 2,700 feet.  If you visit the beaches of Emerald Isle this winter, you may see wood or metal stakes at the base of the dunes that will identify these station numbers as such.

PROJECT PLANNING & IMPLEMENTATION

 

The geographical extents and basic geometries of the Phase III, Post Florence Renourishment Project are included in the accompanying "Key Documents" on top of this webpage, and the Project sequencing as a whole (Phases I through III) was based upon both design and cash-flow considerations.  Weeks Marine and Great Lakes Dredge & Dock furnished bids for the Phase III effort with the former (Great Lakes) providing the lowest awardable bid price.   Great Lakes was also our Phase I and II contractor.  

In cross-section going from the top of the dune seaward, the beachfill will be contoured by; (1) tying into the existing, eroded frontal dune at mostly +12 to +14 feet NAVD 88 and maintaining that top dune elevation at vary lengths as one progresses seaward, (2) the slope of the newly constructed frontal dune will be graded on a 5:1 slope to the elevation of +6 feet NAVD 88, (3) the beach berm (flat part of the beach) will be extended from that point seaward at +6 feet NAVD 88 at varying lengths, and (4) the slope of the fill from the berm crest out to sea will be on a 20:1 slope.  The newly created dune crest and dune slope will be planted (vegetated) with predominantly Sea Oats as part of the contract (see typical cross-section above).  Note: The Reach 5 (East Emerald Isle) nourishment template is "berm only" as dune construction was completed in 2019 as part of the Phase I effort. 
 

The borrow source for this nourishment effort is the Offshore Dredged Material Disposal Site (ODMDS) associated with Morehead City Federal Navigation Project. This dump site is essentially a repository for dredged material historically extracted from the Outer Harbor reach of the navigation channel and based upon experiences with a 2004 and 2007 Section 933 Project that utilized channel material for beach nourishment and the 2004, 2007, 2013, 2019, and 2020 post hurricane projects that actually utilized the ODMDS; we expect the sand quality to be excellent. This also makes intuitive sense, because for the most part, the shoal material that enters the navigation channel at Beaufort Inlet is sand that has traveled from adjacent beaches. Construction, or deepening material that resides in the ODMDS should be avoided. To this effect the firm of Moffatt & Nichol, who has been retained by the Bogue Banks communities as the engineering consultant for the Post-Florence Renourishment Project, has performed additional sediment sampling and analyses in the ODMDS to hone the areas of beach quality sand.