The Newtown Pentacle

- photo by Mitch Waxman

The Friday of memorial day weekend, your humble narrator stumbled into the wilds of Astoria, headed for Astoria Park. Astoria Park is at the western end of Queens, and adjoins the East River, hosting parts of both the mighty Triboro Bridge and the sublime exemplar of bridge engineering called Hellgate. Named for the section of the East River it crosses, Hellgate was my intended destination and subject, and I was hoping for some visually interesting rail traffic to be crossing the great bridge. Frustrated by a gray and humid day, the Acela and other Amtrak traffic was observed, as well as a curious CSX double engine. Then…

from nycgovparks.org

Astoria Park, on the west shore of Queens, extends from south of the Triborough Bridge to north of the Hell Gate Bridge. With a panoramic view of the skyscrapers of midtown Manhattan in the south to the Hell Gate channel in the north, the scenery presents the diverse landscape of New York City. The Hell Gate channel, formed by faults deep underground, contains some of the deepest water in New York Harbor. Its treacherous reefs bear picturesque names such as “Hen and Chickens,” “Pot Rock,” “Bread & Cheese,” and “Bald Headed Billy.”

Throughout the centuries the stunning natural beauty of this location has attracted visitors and settlers. Before the arrival of European colonists, a trail passed by the site, and an Indian village flourished at Pot Cove. Local inhabitants grew maize on the shores, fished in Hell Gate, and drew water from Linden Brook, a small stream that still flows under Astoria Park South. In the mid-1600s the Dutch parceled out this land to various owners, including William Hallet whose grant embraced hundreds of acres. During the American Revolution, several British and Hessian regiments were stationed in the area. On November 25, 1780 the frigate Hussar and its five-million-dollar cargo sank to the bottom of Hell Gate, where despite some removal of cannons, the treasure still remains.

- photo by Mitch Waxman

I’ve become pretty familiar with NY Harbor in the last year, and can identify some of the common types of ships that cross its waters. Every now and then, however, a mysterious craft- an unidentified floating object or UFO if you will- crosses in front of me. Proceeding south, this catamaran (actually a trimaran) was nearly devoid of markings- which is remarkable in itself- and moving at a tremendous clip. Its “colorway” and hull shape instantly said “military” to me, but I could not recognize its specie.

from wikipedia

The first trimarans were built by indigenous Polynesians almost 4,000 years ago, and much of the current terminology is inherited from them. Multihull sailboats (catamarans and trimarans) gained favor during the 1960s and 1970s. Modern recreational trimarans are rooted in the same homebuilt tradition as other multihulls but there are also a number of production models on the market. A number of trimarans in the 19–36-foot lengths (5.8–11 m) have been designed over the last 30 years to be accommodated on a road trailer. These include the original Farrier – Corsair folding trimarans – and original John Westell swing-wing folding trimaran (using the same folding system later adopted also on Quorning Dragonfly) and like trimarans. Many sailboat designers have also designed demountable trimarans that are able to be trailered (like the SeaCart 30 by Oceanlake Marine).

The trimaran design is also becoming more widespread as a passenger ferry. In 2005 the 127-metre trimaran (417 ft) Benchijigua Express was delivered by Austal to Spanish ferry operator Fred. Olsen, S.A. for service in the Canary Islands. Capable of carrying 1,280 passengers and 340 cars, or equivalents, at speeds up to 40 knots, this boat was the longest aluminum ship in the world at the time of delivery. The trimaran concept has also been considered for modern warships. The RV Triton was commissioned by British defence contractor QinetiQ in 2000. In October 2005, the United States Navy commissioned for evaluation the construction of a General Dynamics Littoral Combat Ship (LCS) trimaran designed and built by Austal.

- photo by Mitch Waxman

Evocative, as on one hand it resembled a radar dodging stealth aircraft for the odd angles and aerodynamic shape, on the other it suggested a modern combat tank with its armor designed to deflect rather than defeat ballistic weapons.

The ship, nevertheless, was kicking up a huge wake and was shooting water behind it- some 10-20 feet high- as it rocketed down the East River.

from wikipedia

The littoral zone refers to that part of a sea, lake or river that is close to the shore. In coastal environments the littoral zone extends from the high water mark, which is rarely inundated, to shoreline areas that are permanently submerged. It always includes this intertidal zone and is often used to mean the same as the intertidal zone. However, the meaning of “littoral zone” can extend well beyond the intertidal zone.

There is no single definition. What is regarded as the full extent of the littoral zone, and the way the littoral zone is divided into subregions, varies in different contexts (lakes and rivers have their own definitions). The use of the term also varies from one part of the world to another, and between different disciplines. For example, military commanders speak of the littoral in ways that are quite different from marine biologists.

The adjacency of water gives a number of distinctive characteristics to littoral regions. The erosive power of water results in particular types of landforms, such as sand dunes, and estuaries. The natural movement of the littoral along the coast is called the littoral drift. Biologically, the ready availability of water enables a greater variety of plant and animal life, and the additional local humidity due to evaporation usually creates a microclimate supporting unique types of organisms.

The word “littoral” is used both as a noun and an adjective. It derives from the Latin noun litus, litoris, meaning “shore”. (The doubled ‘t’ is a late medieval innovation and the word is sometimes seen in the more classical-looking spelling ‘litoral’.)

- photo by Mitch Waxman

The “colorway” and camouflage of the craft suggested that the futurists of Britain still have modern adherents, long after the last of the “dazzle ships” were launched.

For those of you not in the know, the Dazzle Ships were an experiment in “breaking up the shape” of large combat vessels against the horizon, an attempt to reduce the visual profile of capital ships and reduce the ability of submariners to target vital areas of said ships. Dazzle works best at distance, which is what modern naval combat is all about.

from wikipedia

At first glance Dazzle seems unlikely camouflage, drawing attention to the ship rather than hiding it, but this technique was developed after the Allied Navies were unable to develop effective means to disguise ships in all weather.

Dazzle did not conceal the ship but made it difficult for the enemy to estimate its type, size, speed and heading. The idea was to disrupt the visual rangefinders used for naval artillery. Its purpose was confusion rather than concealment. An observer would find it difficult to know exactly whether the stern or the bow is in view; and it would be equally difficult to estimate whether the observed vessel is moving towards or away from the observer’s position.

Rangefinders were based on the co-incidence principle with an optical mechanism, operated by a human to compute the range. The operator adjusted the mechanism until two half-images of the target lined up in a complete picture. Dazzle was intended to make that hard because clashing patterns looked abnormal even when the two halves were aligned. This became more important when submarine periscopes included similar rangefinders. As an additional feature, the dazzle pattern usually included a false bow wave to make estimation of the ship’s speed difficult.

- photo by Mitch Waxman

As mentioned, my computer was down for the holiday weekend, but Our Lady of the Pentacle allowed me to use her laptop and I managed to get a few of these images out to that clandestine and anonymous network of maritime enthusiasts and quasi governmental experts who advise, comment, or offer corrections to your Newtown Pentacle. Credit for identifying this craft goes out to them, and I wish that they would allow me to sing praise publicly, but certain conflicts of interest or oaths of secrecy demand that they must always be referred to as “anonymous sources”. In this case, the ultimate sources will be referred to as Daidalos and Icaros (hey, it is Astoria Park).

from wikipedia

It is in images, not in texts that Daedalus is seen with wings; many Greek myths appear to have been invented to make sense of known but inexplicable images. The most familiar literary telling explaining Daedalus’ wings is a late one, that of Ovid: in his Metamorphoses (VIII:183-235) Daedalus was shut up in a tower to prevent his knowledge of his Labyrinth from spreading to the public. He could not leave Crete by sea, as the king kept strict watch on all vessels, permitting none to sail without being carefully searched. Since Minos controlled the land and sea routes, Daedalus set to work to fabricate wings for himself and his young son Icarus. He tied feathers together, from smallest to largest so as to form an increasing surface. The larger ones he secured with thread and the smaller with wax, and gave the whole a gentle curvature like the wings of a bird. When the work was done, the artist, waving his wings, found himself buoyed upward and hung suspended, poising himself on the beaten air. He next equipped his son in the same manner, and taught him how to fly. When both were prepared for flight, Daedalus warned Icarus not to fly too high, because the heat of the sun would melt the wax, nor too low, because the sea foam would soak the feathers.

- photo by Mitch Waxman

Daidalos was actually stumped when the photos arrived, and neither of us could make any sense of the only marking- a string of tiny numbers on the hull- of this unidentified floating object. High flying, Icaros received the shots from the latter, and contacted high ranking members of a certain governmental entity. This entity- let’s just say that they have lots of boats and planes, and boats that are airports, and boats that carry nuclear missiles and stay underwater for months at a time, and a lot of the people who work for it wear white dress uniforms- claimed the ship as theirs!

from wikipedia

From the time of its inception, the military played a decisive role in the history of the United States. A sense of national unity and identity was forged out of the victorious Barbary Wars, as well as the War of 1812. Even so, the Founders were suspicious of a permanent military force and not until the outbreak of World War II did a large standing army become officially established.

The National Security Act of 1947, adopted following World War II and during the onset of the Cold War, created the modern U.S. military framework; the Act merged previously Cabinet-level Department of War and the Department of the Navy into the National Military Establishment (renamed the Department of Defense in 1949), headed by the Secretary of Defense; and created the Department of the Air Force and National Security Council.

The U.S. military is one of the largest militaries in terms of number of personnel. It draws its manpower from a large pool of volunteers; although conscription has been used in the past in various times of both war and peace, it has not been used since 1972. As of 2010, the United States spends about $692 billion annually to fund its military forces, constituting approximately 43 percent of world military expenditures. The U.S. armed forces as a whole possess large quantities of advanced and powerful equipment, which gives them significant capabilities in both defense and power projection.

- photo by Mitch Waxman

What you have just seen, lords and ladies, shooting down the East River at high speed was described as a (JHSV) Joint High Speed Vessel.

A JHSV can comfortably carry 300 fully armed MARINES, or up to 600 in a pinch. Alternatively, it can move multiple main battle tanks- the astounding M1 Abrams. Just so you understand, 600 is near the low end of Battalion strength, and 600 U.S. Marines could probably claim a beachhead in Hell itself if they were asked to. It also has a landing pad for a helicoptor.

This ship is huge… but a helicoptor pad?

from navy.mil

Description

The JHSV program is procuring high-speed transport vessels for the Army and the Navy. These vessels will be used for fast intra-theater transportation of troops, military vehicles and equipment. The JHSV program merges the previous Army Theater Support Vessel (TSV) and the Navy High Speed Connector (HSC), taking advantage of the inherent commonality between the two programs.

JHSV will be capable of transporting 600 short tons 1,200 nautical miles at an average speed of 35 knots. The ships will be capable of operating in shallow-draft ports and waterways, interfacing with roll-on/roll-off discharge facilities, and on/off-loading a combat-loaded Abrams Main Battle Tank (M1A2). Other joint requirements include an aviation flight deck to support day and night air vehicle launch and recovery operations.

JHSV is a commercial-design, non-combatant transport vessel, and does not require the development of any new technology. JHSV is being built to American Bureau of Shipping (ABS) High Speed Naval Craft Guide. Systems onboard will be based on commercial ABS steel vessel rules. As such, it does not require the survivability and ability to sustain damage like the LCS. It has no combat system capability and no ability to support or use LCS mission modules. It will leverage non-developmental or commercial technology that is modified to suit military applications. Select military features include Aviation; Command, Control, Communications, Computers, and (Military) Intelligence; and Firefighting for the Mission Bay. NVR does not apply to any part of JHSV.

As a non-combatant sealift ship, the Navy variant of JHSV will be crewed by civilian mariners, either employed by or under contract to the Navy’s Military Sealift Command. U.S. Army vessels will be crewed by Army craft masters. Both versions will require a crew of approximately 22-40 people, but will have airline style seating for more than 300 embarked forces and fixed berthing for approximately 100 more.

- photo by Mitch Waxman

Technical upgrades have occurred here in Pentacle HQ. A new DSLR, which was quite unaffordable, has been purchased from the unknowable levantines at BH Photo. The trusty Canon G10, in use since its issuance in late 2008, is off to Canon for warranty service owing to the defects that have appeared on its lens. Said scratches seem to originate from the mechanical action of the external housing which are meant to protect the lens element. These scratches have, after shooting some 17,000 exposures in the last year, become quite noticeable and are getting in the way. The G10 will return to Newtown Pentacle service upon repair, and is highly recommended to all for its versatile nature, manual shooting modes, ability to save in RAW format, and crisp lens- although it falls apart in low light and is useless at high ISO speeds. The flash is also pathetic.

- photo by Mitch Waxman

Deciding to take the plunge into the DSLR world, our lady of the Pentacle and myself worked out a budget, and research on what was available in my price point began. Things narrowed to the Nikon D90 and Canon Rebel T1i (or 500D). The Nikon is wielded by a buddy of mine to great effect, and offers the promise of a “full size” sensor. The Nikon ecosystem of accessory lenses and other bits is also a little less expensive than commensurate equipment in the Canon range. The Canon, however, matches the 15 megapixel spec of the G10 (also a Canon) and also offers an operating system that seemed a bit more organic to me. I use a Mac, always have, and have quit jobs that forced me to use a windows PC in the past. Organic matters to me, which is why a Sony camera was never considered. (imho Sony makes the best Hardware-Everything, and the worst software-Everything).

- photo by Mitch Waxman

So, having spent a ton of money I don’t have, the plunge was taken on the Canon T1i and a couple of decent lenses. Of course, this is after “the season” for photography in New York, which is actually most of the time- just not in December and January. Harsh shadow and blown highlights, overcast skies and leaden water- trademarks of the winter sun here in the Newtown Pentacle- the angle and frequency of the light is all wrong except in the early morning and late afternoon. Photography types term this as “golden hour”, which somehow sounds “dirty” to me.

So, on one of the few sunny days enjoyed of late, your humble narrator pulled the filthy black raincoat off its hook and scuttled forth to find what I could find. Hells Gate is always a good choice for experimenting with a new gizmo. Astoria Park is just about as safe these days as you can expect to be when out in public, and there’s always something interesting going on. I shot these with the “long lens”, which is fancy way of saying telephoto.

- photo by Mitch Waxman

That’s the Catherine Turecamo, a 1972 vintage 199 ton 3,200 HP tugboat, operated by the Moran towing company. It was built at the Main Iron Works in Louisiana as the MIss Lynn.

from morantug.com

Moran Towing Corporation has provided tugboat services to the Port of New York since 1860. The company began with Michael Moran’s purchase of-one-half interest in a tugboat. In the years since, the fleet with the white M logo on its stacks has become the largest in the port,and on the U.S. East and Gulf Coasts. The port of New York-New Jersey provides access to the most concentrated and affluent consumer market in the world. Its facilities include terminals operated by the Port Authority of NY & NJ and privately operated terminals. Over 16 million tons of cargo pass through the port on an annual basis, transported aboard various types of ships, including container ships, tankers and barges. The New York division also services the Port of Albany, located 145 miles up the Hudson River from New York City. Albany is a hub for commercial trade in its region, due to its proximity to the New York State Barge Canal and its excellent inland transportation network.

- photo by Mitch Waxman

The new camera was a little awkward to handle at first, and I was self conscious of it as well. This was a big “honking” camera, weighing four times what my familiar “rangefinder-sized” G10 did. I practiced tracking the tugboat with it, zooming in and out and so on. I think the shots came out alright- if you click through to the photo’s Flickr page and check out its larger incarnations- you’ll see some real detail in them. This is one of the places where the higher megapixel count of the Canon matters to me, and justified buying into its franchise.

Trust me on this one, I’m an advertising retoucher photoshop guy by day, and resolution matters. A lot.

- photo by Mitch Waxman

I’m only a couple of thousand shots in, a month later. Its been a busy month somehow, with holiday obligation and hiding in my warm burrow awaiting spring. Meanwhile, I’ll be learning how to use this new gizmo.

Incidentally, on the subject of gizmos, anyone out there have anything to say on geotagging? Leave me a comment or contact me, if you do.

- photo by Mitch Waxman

Hanging out at Astoria Park, waiting for the Greater Astoria Historical Society‘s “Haunted East River” tour to start, what did I spy crossing under mighty Triborough?

The John Reinauer tugboat- that’s what- moving a fuel barge north on the East River, through the bright passage at Hells Gate.

from wikipedia

Liquid cargo barges are barges that transport petrochemicals, such as styrene, benzene and methanol; liquid fertilizer, including anhydrous ammonia; refined products, including gasoline, diesel and jet fuel; black oil products, such as asphalt, No. 6 fuel oil and coker fuel; and pressurized products, such as butane, propane and butadiene, which are transported on the waterways from producers to end users.

- photo by Mitch Waxman

The John Reinauer was built at Main Ironworks in 1969, and was christened the Esso Crystal River. (Esso, is of course, the brand name for Standard Oil -S.-O- Esso, later Exxon) The now Exxon Crystal River went to Reinauer Transportation in 1993. A 2,600 horsepower, 86 foot long steel hulled towing vessel, the J.R. is 27 feet wide and has a draw of 9 feet.

Check out the company’s J.R. page for photos of the ship in its various incarnations here.

from wikipedia

The terms “Tonnage” and “Ton” have different meanings and are often confused. Tonnage is a measure of the size or cargo capacity of a ship. The term derives from the taxation paid on tuns of wine, and was later used in reference to the weight of a ship’s cargo; however, in modern maritime usage, “tonnage” specifically refers to a calculation of the volume or cargo volume of a ship. The term is still sometimes incorrectly used to refer to the weight of a loaded or empty vessel.

Measurement of tonnage can be less than straightforward, not least because it is used to assess fees on commercial shipping.

- photo by Mitch Waxman

Like many other tugboats, the John Reinauer participated in the evacuation of Lower Manhattan necessitated by the September 11 attacks.

(The John J. Harvey Fireboat, which was discussed in some detail in 2 prior posts- here… and here, similarly served the city that day).

from wikipedia

Immediately after the first attack, the captains and crews of a large number of local boats steamed into the attack zone to assist in evacuation and provide supplies and water.Water became urgently needed after the Towers’ collapse severed downtown water mains. The size of the dust and debris cloud following the collapse of the Twin Towers was such that it necessitated that many of these trips were navigated by radar alone. Estimates of the number of people evacuated by water from Lower Manhattan that day in the eight hour period following the attacks range from 500,000 to 1,000,000. As many as 2,000 injured people in the attacks were reportedly evacuated by this means through there were no reported injuries resulting from the evacuation itself.

M/V Red Hook DEP Sludge Vessel - photo by Mitch Waxman

After processing at a water treatment facilities, which the City of New York’s DEP manages 14 of (including the vast Temple of Cloacina called the Newtown Creek Wastewater Treatment Plant), the concentrated sludge distillate produced by municipal sewage plants requires “dewatering” – it must be reduced into a semi solid called “cake”. Not every one of the 14 wastewater treatment plants has a dewatering facility, so the sludge needs to get from point A to point B via a the fleet of Sludge Vessels.

Pictured above is the sludge dock in Greenpoint, with the M/V Red Hook at dock, at the mouth of the Newtown Creek. Flowing from that aforementioned temple of “the Venus of the Sewers” to a gigantic holding tank via mechanical means, it is then pumped out to the dock and the waiting sludge boat.

from nyc.gov

Preliminary treatment

Several stories underground, wastewater flows into the plants from sewers connected to New York City’s homes and businesses. The incoming wastewater, called influent, passes through screens consisting of upright bars, spaced one to three inches apart. These bars remove large pieces of trash including rags, sticks, newspaper, soft drink cans, bottles, plastic cups and other similar items. This protects the main sewage pumps and other equipment. The garbage is transported to landfills. The main sewage pumps then lift the wastewater from the screening chamber to the surface level of the plant.

Primary treatment

Next, the wastewater enters primary settling tanks, also called sedimentation tanks, for one to two hours. The flow of the water is slowed, allowing heavier solids to settle to the bottom of the tank and the lighter materials to float. At the end of the process, the floatable trash, such as grease and small plastic material, rises and is skimmed from the top of the tanks surface.

The settled solids, called primary sludge, are then pumped through cyclone degritters — devices that use centrifugal force to separate out sand, grit (such as coffee grinds) and gravel. This grit is removed, washed and taken to landfills.

The degritted primary sludge is pumped to the plant’s sludge handling facilities for further processing. The partially treated wastewater from the primary setting tanks then flows to the secondary treatment system.

M/V North River DEP Sludge Vessel - photo by Mitch Waxman

The 1.3 billion gallon a day flow of New York City’s sewage should be defined as a third river. That’s 1,300,000,000 gallons a day or 474,500,000,000 gallons of night soil a year. 1.3 billion is the population of China.

Pictured above is the DEP Sludge Vessel M/V North River, a veteran, she was launched at Maryland Shipbuilding in 1974. Just under 324 foot long, North River can carry 102,000 cubic feet of evil juice and weighs in at 2,557 gross tons.

from nyc.gov

Secondary treatment

Secondary treatment is called the activated sludge process. This is because air and “seed” sludge from the plant treatment process are added to the wastewater to break it down further. Air pumped into large aeration tanks mixes the wastewater and sludge that stimulates the growth of oxygen-using bacteria and other tiny organisms that are naturally present in the sewage. These beneficial microorganisms consume most of the remaining organic materials that are polluting the water and this produces heavier particles that will settle later in the treatment process.Wastewater passes through these bubbling tanks in three to six hours.

The aerated wastewater then flows to the final settling tanks which are similar to the primary settling tanks. Here the heavy particles and other solids settle to the bottom as secondary sludge. Some of this sludge is re-circulated back to the aeration tanks as “seed” to stimulate the activated sludge process. The returned sludge contains millions of microorganisms that help maintain the right mix of bacteria and air in the tank and contribute to the removal of as many pollutants as possible.

The remaining secondary sludge is removed from the settling tanks and added to the primary sludge for further processing in the sludge handling facilities.Wastewater passes through the settling tanks in two to three hours and then flows to a disinfection tank.

Disinfection

Even after primary and secondary treatment, diseasecausing organisms may remain in the treated wastewater. To disinfect and kill harmful organisms, the wastewater spends a minimum of 15-20 minutes in chlorine-contact tanks mixing with sodium hypochlorite, the same chemical found in common household bleach. The treated wastewater, or effluent, is then released into local waterways. Disinfection is an essential step because it protects the health of people who use local beaches and enjoy other recreational activities on or near the water.

M/V Newtown Creek DEP Sludge Vessel - photo by Mitch Waxman

Identical in dimension and capacity to the North River, the 1967 vintage DEP Sludge Vessel M/V Newtown Creek passed under mighty Triborough and crossed Hells Gate. M/V Newtown Creek was laid down by the Wiley Manufacturing Co. Back in the days of ocean dumping, these ships were amongst a small fleet of tugs, barges, and older sludge boats that would “do the deed“.

from nyc.gov

Sludge treatment

The following are typical stages of the sludge treatment process.

Thickening

The sludge produced by primary and secondary treatment is approximately 99% water and must be concentrated to enable its further processing. Thickening tanks allow the sludge to collect, settle and separate from the water for up to 24 hours. The water is then sent back to the head of the plant or to the aeration tanks for additional treatment.

Digestion

After thickening, the sludge is further treated to make it safer for the environment. The sludge is placed in oxygenfree tanks, called digesters, and heated to at least 95 degrees Fahrenheit for between 15 to 20 days. This stimulates the growth of anaerobic bacteria, which consume organic material in the sludge. Unlike the bacteria in the aeration tanks, these bacteria thrive in an oxygen-free or “anaerobic” environment. The digestion process stabilizes the thickened sludge by converting much of the material into water, carbon dioxide and methane gas. The black sludge that remains after digestion has the consistency of pea soup and has little odor. This is called digested sludge.

Methane gas is often used as an energy source at the City’s wastewater treatment plants. The gas may be used in engines to produce electricity or directly drive plant equipment. Gas is also used in boilers to provide heat for digestion and plant-wide buildings. Currently, DEP and the New York Power Authority (NYPA) have jointly installed fuel cells at four of the City’s water pollution control plants; 26th Ward, Red Hook, Oakwood Beach and Hunts Point. Fuel cells convert the methane gas and carbon dioxide into heat and electricity that is then used to operate the plants. This technology contributes to New York City’s efforts to enhance clean air operations at its facilities. There is a significant reduction in air emissions as a result of using fuel cells.

Digester sludge is pumped from sludge storage tanks to a dewatering facility. At some treatment plants, where there are no dewatering facilities on site, the sludge is transported for processing through a pipeline or by a sludge boat to a plant that has a dewatering facility.

M/V Newtown Creek DEP Sludge Vessel, close-up – photo by Mitch Waxman

Once requiring a crew of as many of 20, the City now runs these ships with a mere 6. Semiautomated, M/V Newtown Creek and North River are nevertheless more than twice the size of the original model Sludge Vessels like the Owl’s Head.

from nyc.gov

Sludge dewatering

Dewatering reduces the liquid volume of sludge by about 90%. New York City operates dewatering facilities at eight of its 14 treatment plants. At these facilities, digested sludge is sent through large centrifuges that operate like the spin cycle of a washing machine. The force from the very fast spinning of the centrifuges separates most of the water from the solids in the sludge, creating a substance knows as biosolids. The water drawn from the spinning process is then returned to the head of the plant for reprocessing. Adding a substance called organic polymer improves the consistency of the “cake”, resulting in a firmer, more manageable product. The biosolids cake is approximately 25 to 27 percent solid material.