The FIMI Project 2019.
How to build a dune…
By Bob Anderson.
In 2012 Hurricane Sandy devastated much of the New Jersey and New York coasts. Most of Fire Island was hit hard, with many houses severely damaged or completely destroyed. Worse still, the storm devastated the sand dune system that enables Fire Island to serve as a barrier protecting millions of south shore Long inhabitants for over 30 miles.
In the years following Hurricane Sandy Congress appropriated funds to restore barrier islands so they could live up to their name and serve as an effective barrier against future storm damage. For Fire Island, Congress created the Fire Island Inlet to Moriches Inlet project known as FIMI. It allocated some 270 million dollars to harvest approximately 8 million cubic yards of sand from the seabed some 5 miles offshore and use it to recreate the primary dune and elevate the beach in all areas of Fire Island that needed remediation.
These pictures are a chronicle of the work done in The Pines in October and November of 2019.
October 26, 2019
In some of the previous pictures the sand itself looks very dark (partly due to the lighting but mostly because it’s wet).
In this shot you can see its actual color and quality… they are collecting some pretty nice material from ~5 km (3 miles) offshore and depositing it on the beach via the large (1meter, ~3 feet) diameter steel pipes you can also see in this picture. The top of the ‘berm’ (artificial dune) in the foreground is actually 4.5m (~15 feet) higher than the former level of the beach right in front of the houses.
The remainder of the beach is ~3m (~9-10 feet) higher, the consequence of which is that the new high-water line is ~100m (~320 feet) from the houses.
Put simply, it’s a BIG beach!
Two ships take turns gathering sand from the seabed about 5 km (3 miles) offshore, where the water depth is about 20 to 30 meters (66 to 100 feet). The sand is sucked up into large holding tanks inside each ship.
In this picture, the ship in the distance is collecting the sand, and the ship near shore is discharging its load via the large 1 meter (about 3 feet) diameter pipe at the bow that runs to shore to the discharge ends of the distribution pipes.
So that’s where the new sand comes from!
(NOTE: The ships look much closer than they really are because this was shot with a fairly strong telephoto lens).
October 28, 2019
This shot gives a perspective that’s somewhat elevated above the others, allowing you to see more of the beach.
Where as the boardwalk used to end with steps directly down to the beach pretty much in line with the houses, now the boardwalks must ‘fly over’ the new berm (artificial dune) in the foreground, and stretch 60-70 feet toward the water before ending in stairs down to the new sand level, which is about 10 feet higher than the old beach. In at least two places (and perhaps three) there will be ramps not stairs.
October 30, 2019
Local contractors use high-pressure water (from the fire-fighting hydrants) to embed the telephone-pole-sized treated wood pilings needed under a new or raised house. This is a very effective technique, unfortunately it’s also laborious and time-consuming.
The folks rebuilding the beach have a much better toy. It drills down to the required depth, and then a crane lowers the pole into the hollow center. The drill is then reversed back out of the hole and presto… It embeds a 30-foot piling in about 10 minutes.
The former boardwalks ended in stairs down to the sand that were supported by 4×4 inch posts. Not these! The new posts are so relatively massive because they must support new walkway extensions and stairs (or ramps) to the beach that will be much wider and stronger than anything we’ve seen before.
Several people have asked about the ships themselves. They’re far enough from shore they are not so easy to photograph, but this shows the basics pretty well, most especially how the pipe attaches to the bow.
Now that the area where one of the boardwalks will be built is protected by orange fencing, you can get a much better sense of the geometry of the new berm (artificial dune) over which the new boardwalks to the beach must pass.
The berms will be planted with nursery-grown beach grass once all the heavy construction is finished, and protected by sand-fencing of the same type used in the past.
Also visible in this picture are a number of the steel pipes used to distribute the sand-slurry, now in a stack in preparation for moving them further to the west to the next stretch of beach to be rebuilt.
October 31, 2019
This seemingly insignificant picture is actually the most important shot yet…
We have a very high tide and strong winds gusting to 45 mph. That used to bring the water right up to the houses. But now it’s 320 feet away, even under these stormy conditions!
NOTE: The old boardwalk in the foreground collapsed in the high winds because it had been severely weakened due to the demolition work that removed the rest of it in preparation for the new boardwalk system. It was not torn down by water, as has happened in the past. The high-tide line is over 300 feet further away.
So far this project looks to be very successful indeed!
November 1, 2019
The blue temporary mat you see in this shot is there to prevent erosion from workers who have to walk out to the beach. Two days ago it was completely clean, there was no sand on it at all.
But now, because the winds from this most recent storm were from almost due south, there was actually a build-up of sand on the berms (artificial dunes).
So this particular storm helped the beach, not hurt it!
The storm yesterday became more severe last night, with heavy rain and winds gusting to 60mph. The construction workers knew it was coming, and parked all their equipment on top of the berm (artificial dune), out of harm’s way.
The damage that causes doesn’t matter because they have plenty of extra sand to restore any spots that are worn down by the equipment being driven up onto it.
Once the final shaping and profiling of the berm has been done, it will be planted with beach grass, at which point the same restrictions will apply to it as apply to walking on any dune (which is to say, don’t even think about it).
This shot is a good illustration of just how big this beach rebuild is…
Whereas before, at high tide the water was coming under houses enough to seriously erode the sand below people’s decks and pools — causing some to collapse — now the berm is high enough that you could literally step from a pool deck right onto the berm without spilling your martini! (But don’t, of course).
November 4, 2019
This shot gives you an idea of the height of the new berm (artificial dune) relative to a point about halfway down the old steps to the former beach level. If it were possible to stand at the level of the old beach, then the berm would appear to be 4-5 feet even higher than in this picture.
The berm itself runs the length of the Pines. At the base it’s about 18m (~60 feet) wide, while at the crest it’s about 11m (~35 feet) wide. The high-tide line is then about 85 meters (~280 feet) beyond the berm.
The poles will support a new and much stronger walkway over the berm and out to the beach.
Work has resumed! Only now the crews are building the beach from the west end of the Pines eastward to the spot they stopped (just west of Cedar) when the storm arrived last week.
The picture was taken by one of the beach reconstruction workers who was kind enough to walk the camera out on the dune (he’s allowed) and grab this shot for us.
Telephoto shot of the bulldozers building the new beach, now starting from ‘The Rack’ and moving eastward to the point where worked stopped near Cedar Walk. I don’t know why they didn’t continue to build westward starting at Cedar again, but there you have it. (It may be related to picking a central spot for the 1km (3,000 feet) long pipe that comes in from the ships to support continued work to both the east and west, but I have not ascertained the actual reason yet).
November 5, 2019
This time of year, the sun sets directly in line with the beach. That allows for some cool compositions and delightfully dramatic pictures!
November 6, 2019
It takes BIG pipes to move a million cubic yards of sand…
This is a high-power telephoto shot of one of the ships fully loaded with sand and riding so low in the water it’s a little scary. In this picture it’s about 3 kilometers (2 miles) offshore, and slowly approaching in preparation to connect with the offshore end of the pipe system in order to discharge its cargo.
On this part of the beach, at Oak walk, only the berm (artificial dune) has been built. It’s not yet at the full height, but from this perspective you can get a sense of scale that’s difficult to see when you’re looking out toward the ocean.
When finished, the berm will top off at about 4 feet higher than in this picture. The level of the beach itself will also be quite a bit higher, of course.
These pictures, taken at Coast Guard Walk, are a great reminder of why this project is so important. Of course, you’d have to be living under a rock not to know that already, but hey, people can be very strange sometimes.
In any event, let’s compare these “Before” pictures with what the same spot looks like “After” the project is completed in a couple weeks… stay tuned for that!
Here’s a different way to understand the size of the berm … this is a shot of the new poles that will support the ‘bridge’ over the berm, photographed before the berm has been constructed.
The sand will come to within a couple feet of the tops of the poles, and then taper down to a new and much higher beach level.
Previously, when you got to the end of the boardwalk you simply descended steps down to the beach. Soon you’ll have to walk up several steps first, cross over the berm, and only then down to the beach.
November 7, 2019
Here’s the same shot as above, now marked with the approximate height of the new berm and beach. All in all, the berm will be 15 feet higher than the current level of the (badly eroded) sand, and the beach will be 9.5 feet higher. So, standing on the new beach and looking back at the berm, it will not appear very tall (only about eye-level, 5.5 feet higher), but the visible part will just be the top third of what actually gets built.
Once it’s all done, to get to the beach, you’ll ascend a few steps from the current boardwalk to cross the ‘bridge’ over the berm, and then steps back down to the beach. In some cases there will be ramps on both ends instead of stairs.
November 8, 2019
Come ‘on…. Please bring us the sand!
Today’s crisp and clear weather allows the best telephoto shot yet of one of the sand collection ships!
November 11, 2019
Here’s a helpful side-by-side comparison of the beach reconstruction. It’s not yet finished, but you can get a pretty clear idea of the size of the berm (artificial dune) and new beach from this…
Work has resumed from east to west. The new berm / beach has now reached Coast Guard Walk. For safety requirements, workmen are fencing off the area where the new steps will be built (none have been, yet).
The bulldozer in the background is building up the new beach just past the new berm. The two vertical posts near the front of the machine with white knobs at the top are precision GPS receivers used to help guide the operator to place the sand in precisely the location and to the height specified.
This is what the sand-pumping looks like in action… FIMI SandPumping
Beach reconstruction has resumed moving from east to west. It’s now up to Coast Guard Walk and advancing by about 300 feet per day!
In very round numbers, that’s about 33,500 cubic yards of new sand laid down per day! Pretty impressive.
Let’s put that number in perspective… that’s enough sand to fill all 310 swimming pools in the Pines every day.
November 13, 2019
This shot shows what the berm (artificial dune) and walkways will look like once they are complete. In the Pines none have been built yet, but everything should be finished by late spring, 2020.
So… Why is all this happening?
The Fire Island Inlet to Moriches Inlet (FIMI) Project is a one-time-only placement of sand to stabilize Fire Island until the larger Fire Island to Montauk Point (FIMP) project is implemented. The local sponsors are Suffolk County and the New York State Department of Environmental Conservation. The project is designed and funded by the US Army Corps of Engineers, and implemented by private contractors.
In other words, although what we’re seeing now is the full extent of what we can expect for the next few years, eventually there will be even more to come. Don’t hold your breath on that, though, because the larger FIMP project has been on the books for a very long time, and no one knows when it might finally become a reality.
In the interim, however, this is a much-needed shot in the arm for all of the communities on Fire Island, especially including the Pines.
How do the ships collect sand, and what happens then…?
Two ships known as “Hopper Dredges” are used to collect material from sand-rich areas between 5 and 10 kilometers offshore (3 to 6 miles) at a depth between 20 and 40 meters (66 to about 130 feet). A huge ‘vacuum’ on each ship sucks up sand and water, which then flows through filter gratings to remove debris and into huge onboard holding tanks. The sand in the holding tanks sinks to the bottom, and the excess water drains overboard through specially-designed overflow pipes.
When the ship is full, it moves to about one kilometer (3,000 feet) offshore as you see it here, and connects to a steel “feed pipe” resting on the seafloor. You can see the top end of that pipe in the picture, at the bow of the ship facing the camera.
Typically the feed pipe is placed perpendicular to the shoreline and moved only infrequently because of its size. At the point the feed pipe reaches the shoreline, it is connected to distribution pipes that turn 90 degrees to run parallel to the beach. They terminate with distribution nozzles designed to spew the sand in a bubble-shape to slow down the flow.
Aboard ship, the sand in the holding tanks is remixed with water using powerful water jets and pumped through the pipe system to the work area. The sand spews out the end of the pipeline through another close-mesh grating that serves as a fine-screen filter to eliminate smaller debris. Bulldozers then flatten the mounds of sand to form the new beach.
The pipe sections are about 10 meters (~30 feet) long and 1 meter (~3 feet) in diameter. Pumping is paused once an area is filled with new sand, and the bulldozers get to work. A specialized pipe-carrying bulldozer adds one or two more pieces of pipe and pumping resumes another 10 or 20 meters (about 33-66 feet) further along the beach.
Nominally, work continues 24 hours a day, but inclement weather, rough seas and mechanical issues can halt operations. Wear and tear on equipment can be a big problem, the sand slurry is very abrasive and maintenance can be challenging at times. Still, the crews are professional and efficient, and work has progressed with remarkable speed.
As for the ships themselves, they contain sleeping areas, full kitchen facilities, medical units and office space. They weigh several hundred tons and carry extremely powerful pumps to transport the sand to shore.
November 15, 2019
In the Fire Island Inlet to Moriches Inlet (FIMI) Project, exactly where are those inlets anyway?
Fire Island Inlet is at the western end of the island, about 8 kilometers (5 miles) west of the Lighthouse. Almost exactly 50 kilometers (30 miles) to the east, the island ends at Moriches Inlet. It used to be one contiguous island until hurricane Sandy breached the island east of Davis Park. These features are noted on the attached Google Earth Image, along with a pushpin marking The Pines.
The pipes that carry the sand are large and heavy, but the crew has two specialized machines that pick them up and move them around like they were a child’s toys. That agility is part of the reason the project can lay down new sand so fast.
Preparing to install pilings at Coast Guard Walk to support the ‘bridge’ over the new berm (artificial dune).
The big rig you see in this picture is actually a drill that penetrates 30 feet into the sand. A treated wood piling (like a telephone pole) is then inserted into the hollow center of the drill. This big machine turns it into a very fast process… about 10 minutes per pole.
There is also a vehicle access ‘cut’ there, which will be sculpted into the berm and covered with crushed bluestone rock in such a way that service and emergency vehicles can cross over the berm without damaging it. This has been done in several places along the length of the island.
Is anyone curious about the new inlet cut into Fire Island by Hurricane Sandy in 2012?
Especially, doesn’t it mean that there are now TWO Fire Islands? And if so, why hasn’t one or the other been (re)named?
The technically correct answer is, yes, that’s exactly what it means. But as usual, the scientific and political realities are more complicated than that.
In the years after Sandy wrecked its havoc on the New Jersey and New York coastlines, a series of studies were performed to understand what the effects of the storm were (to better predict future impacts) and to determine what remediation might be needed and how effective it would be. At the time, the gap Sandy cut in Fire Island was only about 250 feet wide.
One of the many conclusions of those studies was that this gap would likely close itself.
That has not happened. Instead it has grown 5 times wider to about 1250 feet, and deepened considerably. It has changed the way bay and ocean water mix, and altered the bay’s ecosystem. Depending on who you talk to, some of those changes are good and others are bad. But all of them are the consequence of an act of nature in an area of the island NOT grandfathered in as a community.
Consequently, the decision was taken to do nothing about the new inlet. So unless nature changes its mind and decides to fill it in, sooner or later yes, there will be TWO Fire Islands on the map! And one of them (the eastern one, presumably) will need a name.
Most people on Fire Island live or vacation in the western half of the island, so I doubt very many of them will care if it’s the eastern part that gets renamed. But if for any reason the government decides to rename the western portion, I propose we organize a naming contest!
I don’t suppose “Fantasy Island” is available?
November 19, 2019
Now we can see that there will be ramp access to the beach at Coast Guard Walk… here are the pilings that will support a shallow, switch-back ramp all the way down to the sand.
The walkways (and ramps) are wider and much stronger than what we’re accustomed to, with both wood and metal handrails and slatted sides. If everything stays on schedule, that installation will begin in about 2 weeks.
Workers are now in the process of moving the feed pipe to the west end of the Pines in preparation for the last phase of the beach replenishment!
The pipes in the distance are so high in the air (see inset) because that’s how high the new beach level will be, once they start pumping.
There’s only about 1,200 feet remaining to fill with new sand…
This shot features the sand pipe (inactive and now being moved to the west end of the Pines, see next post below), but what it really shows is the sheer size of our new beach… it’s as wide as a football-field is long!
November 20, 2019. Watching every grain of sand they move…
November 21, 2019
Beach replenishment continues! Not much left to go now.
After a few days absence, both sand collection ships are back and busy!
November 22, 2019
Delivering walkway materials… construction on that begins soon!
Still pumping! (the blue matting provides temporary beach access).
Almost done reconstructing the beach! There’s just a few hundred feet to go…
Also, this picture provides another way to understand the scale of what’s been built here… if you look at the bulldozer on the left, you’ll see two people standing near it, appearing rather tiny. THAT is how wide the beach is.
This shot, taken this past summer from the top of the lighthouse, shows just how narrow, fragile (and flat) Fire Island actually is. And yet it and the other islands off the south shore of Long Island are the ONLY barriers protecting millions of people and tens of billions of dollars of real estate on Long Island itself, which is almost equally flat and vulnerable to severe storms.
So, although there is no question that the FIMI beach and dune reconstruction directly benefits the communities on Fire Island, it would be wrong not to consider the massive benefit delivered to millions of people on Long Island, most of whom have never stepped foot on Fire Island.
The even larger Fire Island to Montauk Point (FIMP) project – approved years ago by Congress – is intended to extend that protection to nearly all of the 8 million people who live on Long Island, not just those in the approximately 30 miles of coastline protected by this particular barrier island. That project has yet to happen, and no one knows when it might, but as sea level slowly creeps higher and hurricanes gradually become more severe, reinforcing all of the barrier islands from Brooklyn to Montauk will become ever more essential to protecting the economy of much of the NY metropolitan region.
Put simply, this project benefits everyone in the region, not just a handful of folks fortunate enough to own summer houses on any of these barrier islands, stretching from the Rockaways through Fire Island and out to the Hamptons and Montauk.
November 23, 2019.
The beach restoration crew is almost done placing the sand. In total, about 850,000 cubic yards have been put in front of The Pines, with another 150,000 cubic yards to the east and west tapering into the national seashore areas.
The sand replenishment work is expected to finish by about December 1st. Then the entire beach and berm (artificial dune) will be graded into their final shapes. The berm will then be planted with beach grass and the ‘flyover bridges’ and stairs or ramps to the beach will be finished (some of that has already started — see next posts).
So, how’s it all turning out…?
In a single word, the new beach is HUGE !
Previously, standing where the camera is now, you’d be neck-deep in water.
Walkway and ‘dune flyover’ construction has already begun.
The new construction is wider and about 10 times stronger, making what we had before look rickety by comparison…
Note: The blue mat on the right provides passage over the new berm for temporary beach access in a way that’s safe for the dune for short-term use.
November 25, 2019
Supports for the steps from the ‘bridge’ over the dune down to the beach at Atlantic walk. Depending on the walkway, there will be between 8 and 10 steps down, or a ramp with a switchback to allow for a shallow slope.
Preparing to begin the ‘bridge’ over the dune at Atlantic Walk.
Nearly done replenishing the sand!
November 26, 2019
Except for a small slice on the far west end of The Pines, the sand restoration is now complete. They’ll fill that final part soon. The current sand feed pipe is being dismantled, and soon the beach will get its final grading. Then the heavy equipment will disappear, leaving only what’s needed to build the walkways.
I suppose if you’ve see one new walkway superstructure you’ve seen them all, but it’s interesting to note that they have progressed up to Cedar Walk now.
The strength of these new walkways is impressive — whereas before the walkways were held up by spindly 4×4’s embedded 6 feet into the sand, now they are held up by telephone-pole-sized pilings embedded 30 feet deep.
Previously, the joists that held the walkway runners were 2×6’s, now they are 3×10’s. The old joists were fastened with nails. The new joists between pole pairs are fastened with 1 inch diameter galvanized steel bolts.
This is strong stuff. And it needs to be. The walkways soon to be built are wider and much better designed.
As in several other places, the crew has provided temporary steps and blue matting for people to access the beach from Cedar Walk.
November 27, 2019
This shot, taken at Cedar Walk, gives you a better sense of the height of the berm (artificial dune).
After crossing the ‘bridge’ that traverses 60 feet over it, you’ll walk down 6 or 7 steps to a short landing (lower posts you see between the legs of the higher ones).
And then from that landing you’ll walk down 4 or 5 more steps to the actual beach (which itself is almost 10 feet higher than it was before).
This shot also shows just how robust the supporting structure now is.
This shot, taken looking east from Cedar walk from the top of the berm (standing on the blue mat provided for temporary access), shows the newly graded and finished beach.
All that remains now is to complete the new walkways and stairs / ramps, and fence and plant the berm with beach grass.
December 7, 2019
Walkways begin at Sail Walk…
Extremely strong new walkways are being constructed over the new dune, ending in steps to the beach.
The new walkways are a bit wider and much nicer than anything we’ve had in the past. Most end in stairs, but a few are being built with ramps.
For those of you who are more mechanically-minded, you may be interested to know that all the bolts in these new structures are galvanized, as you’d expect. What’s more gratifying to see are that the clips and nails are all stainless steel. This thing is extremely well built.
January 2020 Sea grass Dune planting.
Why is it so important to keep off the dunes? Theses sea grass plants root deeply into the sand to build a stronger more stable dune. Any human interference will negatively impact the structural integrity and jeopardize the sustainability of the beach.
Beach grass planting has begun on the new dune, which is about 80 feet wide and 7 feet higher than the new beach level, making it 15 feet higher that the old beach level.
As with the beach replenishment, the work is proceeding east to west. Approximately 488,000 seedlings will be planted, spaced roughly 12 inches apart over the entire surface of the dune. It takes 2 to 3 years for the grass to send out enough new roots to cover the dune lushly and lock all the sand in place.
Here’s a couple shots of the prefabricated walkway and stair sections — doing it this way makes the onsite work go a lot faster…
The stairs are being constructed down several steps below the new level of the beach in anticipation of future erosion.