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16 May 2014

Designing A Modern Dockyard

14 May , 2014

Fig. 1: Special Ammunitioning Facility (R.N.)

Dockyards have often grown from older historical bases by “Alteration and Additions” during spikes of modernisation and expansion dictated by evolving rivalries between maritime nations. As the needs of a deep ocean fleet were not anticipated earlier, such expansions were necessarily constrained by the inherent embryonic limitations of the original site. Any nation aspiring to global naval status needs to carefully reformulate its strategy in developing the kind of dockyard necessary to serve its blue water fleet. To do that, one needs to know what is meant and included in such a modern facility. This submission does not propose or detail any specific alterations to existing dockyards. That task is best left to the reader and analyst who using the parameters set out herein will be able to make a quantitative assessment of how to address specific shortcomings if any.

A well planned design of a dockyard must necessarily depend on a futuristic vision of the navy…

The strength of a navy is usually expressed as the number of warships in each of the different categories that make up its fleet. Little mention is made of their operational effectiveness; a measure which best represents the ability to deploy those assets at a given state of readiness in a sustained manner. In reality, the true strength is dependent on both parameters. Shareholders, who are owners of merchant fleets, have long recognized this. It directly affects their income. Management of large fleets now insist on Reliability Modeling during development so that they can prioritize their budget and determine targets before operations begin. Once in commission, they incessantly monitor fleet availability and search for ways to reduce the operational down time. It is surprising that maritime nations and governments seem less concerned about the status of their very expensive naval fleet. Even without the use of dedicated repair facilities, the mission readiness of civilian fleets is consistently much higher than that of most navies. This gap continues to widen.

Since Independence, there have been large increases in public expenditures for higher education. As a result, the country now has a substantial pool of naval architects and engineers. It is, therefore, difficult to reconcile that naval ships and submarines continue to be repaired or modernised overseas in countries that have smaller numbers of such professionals. The reason for this anomaly is that the available tooling and productivity in warship repair are well below necessary levels. One of the more important factors that govern the operational efficiency of any Navy is the quality and capacity of its dockyards that are entrusted with the care of its ships.

Dockyards have often grown from older historical bases by “Alteration and Additions” during spikes of modernisation and expansion dictated by evolving rivalries between maritime nations. As the needs of a deep ocean fleet were not anticipated earlier, such expansions were necessarily constrained by the inherent embryonic limitations of the original site. Any nation aspiring to global naval status needs to carefully reformulate its strategy in developing the kind of dockyard necessary to serve its blue water fleet. To do that, one needs to know what is meant and included in such a modern facility. This submission does not propose or detail any specific alterations to existing dockyards. That task is best left to the reader and analyst who using the parameters set out herein will be able to make a quantitative assessment of how to address specific shortcomings if any.

It is difficult to reconcile that naval ships and submarines continue to be repaired or modernised overseas…

At the start, it must be emphasized that a dockyard is not a stand-alone establishment. It is an intrinsic part of a much larger size naval complex with dedicated zones for fleet administration, military and civilian housing and their medical care and other needs, fuel and lubricant storage farms, warehouses for logistics, ammunition depots and handling wharfs, military engineering services, naval satellite communications and a naval air base. The quality and description of these entities, the supporting infrastructure and transport and their inter-relationship directly affects the performance of the navy as a whole. History shows that despite the added cost of a new industrial complex, the shifting of any industry out of an urban centre has always been extremely profitable to its owners. Therefore, area location of any naval complex from a mega city can be considered as a practical and a very attractive economical option that merits in-depth consideration.

Fleet Vision

A well planned design of a dockyard must necessarily depend on a futuristic vision of the navy. This projection is not entirely virtual. It can be deterministic when based on the combination of the historical and projected the growth of the Gross National Product (GNP) of countries that have influence in the region, the weighted size of their fleets and their shipbuilding capabilities. The US and China are the two other major countries with influence in the region. A projected likely size of their fleets for the next two decades is shown in Table 1.

CATEGORY CHINA – US
Aircraft Carriers (Nuclear/conventional)
6
12+
Attack Submarines (N: Nuclear D=Diesel)
52-D/6-N
52 –N
Ballistic Submarines Nuclear
4
13+
Guided Missile Nuclear Submarines
2
4
Destroyers/Frigates
84
74
Littoral Combat/Minesweepers/SUV Carriers
53
80
To contain any outside threats in the Indian Ocean, it will be necessary for the Indian Navy to keep abreast with 200 ships…

It is also worthy of note that during this period, despite what may appear as a narrowing gap in fleet strength, the US will endeavour to maintain its lead. This would be possible through their innovative skills in such diverse fields of engineering as nuclear, quantum computing, fuel Cells, electronic counter measures, cyber security, super conductivity, high strength alloys, paints, gas turbines, lasers, acoustics, nano-robotics and AUV/SUVs. Should there be a formal declaration of war, the numbers tabulated could easily be doubled by both countries using their established reserves and new construction capabilities.

To contain any outside threats in the Indian Ocean, it will be necessary for the Indian Navy to keep abreast with a minimum fleet size of approximately 200 ships of similar types shown above. It must be assumed that half of these numbers will be based on each coast. Such an allocation is justifiable since no adversary with a global perspective is likely to dedicate more than half their naval assets to a specific regional conflict.

Capacity

Dockyards, also called navy yards, are essential for the specialised repair and care of the fleet. The capacity of a dockyard in terms of the integral fleet load needs to be defined and reviewed at the highest level. This is normally done for both – a peace time normal shift of eight hours and for a war time scenario using three shifts round the clock. In peace time, the dockyard should have the capacity to take on an additional five per cent work load due to unforeseen incidents and handle possible requests from allied navies. When dockyards are distinct and separated from each other due to topography, it is logical to assume that under war time conditions one of these parent bases may no longer be serviceable. Under such a scenario, the capacity of the surviving yards ought to be 100 per cent of the total fleet requirements using three shifts.

Special Requirements

A few of the special requirements specific to a modern dockyard are discussed below:

The Outside World

The perimeter of any large dockyard should be at least ten kilometres away from any major city or any centre of concentrated population. The probability of extensive fires due to wars, mishandling of inflammables, electrical shorts and giant explosions due to explosives and radiation leaks in any naval base over a 200-year period are extremely high. Their effect on the outside world cannot be ignored. The massive explosion in a small 7,000-tonne dwt. freighter ‘Fort Stikine’ in 1944 at a berth in the commercial dock in Mumbai should not be forgotten. That blast was heard over a distance of 15 kms and resulted in a loss of 800 lives, a dozen ships and extensive material damage. Since then, archives show that serious accidents of considerable magnitude have also occurred in naval yards and harbour entrances, even in times of peace.

Fig. 2: Docking Facilities

In any country, a city centre and more so, a prime commercial district contributes far more to the Gross National Product when any land therein is used for commercial purposes instead of being used for a limited semi-industrial activity such as found at a naval complex. As proof observe that at the end of the last century, repair shops and garages in Connaught Place, New Delhi and the Shanghai Bund relocated without much fanfare. They have been replaced by high-end commercial shops and offices. The relocation of the historic Jiangnan Naval Arsenal in SE Shanghai built in 1865, the Admiralty Shipyard Leningrad built in 1705, the Danish Naval base at Holmen and others are also very relevant. As countries raise their living standards, planners are fully aware that the public will not accept the wanton exposure of large numbers of civilians to a permanent high risk of danger. It makes good sense and intelligent planning for any large naval base to be located away from major cities especially those expected to grow to mega cities in this century. The need to stay away from a dockyard can be easily perpetuated if lands adjacent to a new naval complex are designated ‘Restricted’ like a cantonment. In any case, good planning demands that some land reserve adjacent to a new dockyard be held for any required expansion of the yard at some later date.

Fig. 3: Other Alternatives

A naval dockyard employs large numbers of civilian industrial workers who on their very limited incomes, cannot afford the high rents for accommodation within a growing city. As an example, in Mumbai, a dockyard employee’s only housing option is at their old housing colony located over 30 km away from their place of work or even further on the outskirts of the city. They are entirely dependent on public transport. As the population density in the city has increased rapidly, the suburban railway systems in urban areas are overcrowded. In Mumbai, at peak times, up to 6,000 rail commuters are packed in a twelve car rake designed to carry 2,200. Many make a daily commute over one and a half hours each way by rail/bus; most of which is done standing. They are often physically spent when they arrive for work thus reducing the overall productivity. A new naval complex that included civilian housing in closer to their work place could provide yard workers with better quality accommodation and a more relaxed and cheaper commute, free of the heavy air pollution found in a large city.

Any nation aspiring to global naval status needs to carefully reformulate its strategy in developing the kind of dockyard necessary to serve its blue water fleet…

Design Loads

The design of every building, dry dock, syncrolift, marine railway and piers in a dockyard must when loaded, be able to contain the forecasted extreme seismic earthquake and wind spectrum for that region. Further, all wharfs, piers and jetties must also be capable of meeting the design wind and sea spectrum loads acting on vessels berthed at those piers. The possibility of sea level changes due to global warming must also be catered for. A design review of existing facilities using international building codes and Mooring Analysis could reveal many failures. It should be noted that such certifications are routinely required when navies and cruise liners use commercial facilities beyond their home port.

Fire Resistance and Protection

The application of fire engineering is most essential in the design of any dockyard. This is often very poorly addressed and more often, totally neglected as inferred from the lack of any historical documents. These valuation and assessment studies with proper sealed documentation for individual centres and the whole yard must include waste collection/disposal, fire detection, active fire protection both afloat and land based, passive fire protection, smoke control and management, escape facilities and emergency exits, building design, layout and space allocation, quality assurance inspections, training and drills, fire dynamics and modeling, human behaviour and communication failure predictions during fires, risk analysis of remaining assets during a fire including air space, basin and dry dock management during a fire, and prevention of any failures due to lightning flashes and strikes.

Operations involving loading or unloading of ammunition between ships and shore should not be permitted within a dockyard. Separate facilities away from the yard are essential. Fig. 1 (give above) shows such a facility recently commissioned by the UK in compliance with this requirement.

Control

The air space over a dockyard must be permanently closed to civil aviation and restricted to permitted service aircraft only. Similarly, the maximum zone safe TNT load, missile and torpedo fuel and engine fuels and lubricants allowed at one time at every pier, jetty or workshop centre and on main traffic zones, must be established and enforced. A Yard Safety Board that shows the principal hazards and quantities in real time together with their locations in berthed ships, piers and centres is essential. Similarly, safety issues connected with the handling and towing of nuclear ships/submarines, radio-active and medical waste within the dockyard, evacuation routes for residents and the first-aid facilities in the adjacent naval complex and civilian sites need to be assessed, catered for, documented, tested out by exercises and controlled in real time.

The design of every building, dry dock, syncrolift, marine railway and piers in a dockyard must be able to contain the forecasted extreme seismic earthquake…

Services

Electricity, water, waste water, compressed air and communication services are required by every centre, berthing pier, dry dock and repair berth. The expense of a reinforced service tunnel for housing and distribution of these services is minimal compared to the lifetime costs and delays when using alternative above surface methods. Similarly, a central reinforced underground remotely operated main suction connecting all the docks to a central pump house is also desirable. The electrical and fresh water requirements of a dockyard deserve special mention. Alternative sources and local reservoir capacities ought to be carefully assessed to ensure these are adequate. Through the widespread use of solar and wind farms and solar distillation, the new complex could be a net exporter of power and fresh water to an adjacent city. Demands for services at finger piers and dry docks are best serviced by piping led through a service tunnel through a Services Office located at the head of the pier or dry dock. The containment and disposal of leaked reactor coolant, oil spills, medical waste from ships at berths and contingency measures in the event of outages or strikes, are also part of the services that must be planned for and refined by simulated periodical tests duly documented.

Security

Asymmetric warfare by terrorists is a new threat and a reality which needs to be addressed. The outer land perimeter of the dockyard must be secured by a continuous heavy-duty concrete wall with a double barbed wire top and an inner security pre-fab siding spaced 15 metres away from the outer wall. This safety zone should be monitored by automated day and night optic and audio surveillance equipment. The space between fences ought to be concreted over for high speed motor access to deal with any threat. At the sea end, the entrance to the yard must be confined to a passage between two gateway buoys with surface radioactive sensors and trainable cameras. The drill for entering the naval basin from other ports must also include an underwater inspection. This bottom search for explosive devices is best done by diver-assisted Unmanned Submerged Vehicles fitted with underwater cameras and lighting.

The navigation of all marine traffic in the basin ought to be controlled from a Harbor Master Control tower similar to that seen in an airport or at the Port of Rotterdam. Vehicle and pedestrian traffic to the yard must be monitored by face recognition software, PIN scans and electronically filed in real time. All commercial vehicles entering the yard must be automatically scanned for explosives and radioactive materials from the underside and top sides. To ensure drive-through suicidal raids are not possible, twin-set automatic steel armour entry barriers spaced thirty metres apart are mandatory.

Fig. 4: Possible Location for a Dockyard and Fig. 5: Aerial View of the Indian Sub Continent

The yard must also maintain a designated high speed security boat available on a 24/7 basis. All incoming electronic, radio-active and photographic equipment should be documented and controlled. The meta-data gathered must be preserved for at least a year and reviewed continuously for any abnormalities.

Berthing

Berthing at piers for 60 per cent of the entire naval fleet and 100 per cent of its yard craft, should be catered for. An adequate vehicle parking space for the crew should be provided adjacent to the main piers above their main cross connecting road. Because of the huge difference in design loads, the walled sea-front should be divided into sections dedicated for aircraft carriers, submarines, destroyers and cruisers, littoral craft and naval auxiliaries and yard craft separately. Finger piers from the sea-front are far more advantageous than linear or necklace piers. They offer better protection from the sea and reduce the overall siltation especially when they are located transverse to the flow.

Each pier and open dry dock must be serviced by two or more 50-tonne electric cranes capable of radially tracking to both sides. The length of the finger pier should exceed 30 per cent of the largest aircraft carrier. Bollards and fairleads should be load tested every five years and tagged accordingly. In general, ships must be moved to sheltered waters when forecasted sea conditions approach 80 per cent of the maximum design conditions.

Keeping Dry

The underwater repair and maintenance of a ship requires it to be out of the water in a dry environment. To achieve this, ships, submarines and dockyard auxiliary craft can be docked using any of the following methods described below and shown in attached Figs 2 and 3 (above).

Graving Dock

These could be fully relieved, partially relieved or solid. The relief refers to the hydrostatic load from sea water seeping in and acting on the buried surfaces. The water-tight integrity at the entrance of a graving dock is maintained either by one or more hinged buoyancy gates, horizontal sliding caisson or a wedge-shaped vertical sliding caisson. Solid Graving Docks either gravity or tension pile assisted are most desirable.

Fig. 6: Continental Drift
Floating Dry Docks/Barge Lifts

The former consists of a bottom sectioned pontoon with fixed vertical wings. The latter consists of a sectional barge whose buoyancy can be controlled. As they operate in water continuously, they are prone to corrosion in sea water which causes a short life span relative to a graving dock and ever increasing maintenance demands.

Marine Railways

A platform which can travel on rails into the basin and return to land with the vessel docked on it.

Vertical Syncrolift and Transfer System

A floating dock makes use of the buoyant force of the pontoon. In a Syncrolift, the ship is transferred to a platform lowered to the appropriate depth. The platform with the vessel on it is then hoisted up on to land by electric winches installed on either side of the platform. The winches are designed such that they can heave up the platform at a constant rate according to the weight distribution of the ship. Once at land level, the vessel is shifted transversely or longitudinally on trolleys at the traversing station. Therein forced parking must be zoned for fire safety and designed to accommodate the required crane facilities. A submarine hangar for specialised submarine repairs is best located in line with the lift. Ships up to 30,000-tonne DWT are now routinely lifted on a Syncrolift.

Dockyards were initially set up to be centres of unmatched technical excellence and speed specializing in complex engineering of strategic importance…

Barge Crane for Lifts and Tests Afloat

These can be dumb, tug-assisted or self-propelled. For a large yard, the latter is preferable. In order to service the fleet described earlier, one should expect to see all or most of the following major facilities in a modern dockyard on each coast. These estimates are determined on the basis of current intervals for routine hull maintenance and ‘half-life’ refits. It is assumed that external bottom grooming and surveys will be done by modern robotic crawlers to reduce the time spent in dock.
Two 350-metre length dry docks for carrier repairs.
Four 250-metre length preferably covered dry docks for destroyers/frigates/auxiliaries.
An 8,000-tonne Syncrolift for submarines; a re-enforced traversing bay and a holding park for not less than six submarines/small craft both active and reserve. A submarine hangar at the head of the Syncrolift is essential for refit work.
A 500-tonne marine railway for smaller naval and yard craft. Tugs, barges and yard transports often have minor accidents frequently. These usually involve ropes and flotsam around their shafts/propellers. They need to be quickly hoisted, repaired and returned to work. Since a marine railway extended into the basin has the minimum of tidal constraints, it allows for a quick repair and is, therefore, the preferred option.
A 1,000-tonne self-propelled heavy lift barge crane for yard and naval salvage lifts prior to docking.
A segregated 150-metre length covered Dry Dock dedicated to nuclear submarines. A precision Gantry Crane for nuclear refuelling and rail head to accommodate the heavy coffins for the spent hot fuel rods removed during a planned overhaul or post accident repair and a link to the designated graveyard should be integrated in the design.

Fig. 7: Island City – Dubai
High tensile steel welding repairs cannot be done in the open in conditions of hundred per cent humidity or in wet weather. Because of the monsoon, these conditions occur more than 14 weeks per year on either coast. Likewise, the underwater painting of ships using high performance and expensive paints requires very careful surface preparation of the ship’s bottom which should be dry. The thickness of the anti-fouling coating is especially important since the thickness at every spot must be sufficient to ablate over the guaranteed interval between dry dockings.

Whilst the demand by the General Staff for improved docking intervals never ceases, the two legitimate “dry” requirements stipulated in the existing standards are ignored during wet weather to satisfy schedules. Such actions only result in premature paint failure, external shell corrosion and embrittlement cracks in welds. Detection and repairs of such defects are very expensive and time intensive. Under wet weather conditions, the specified “dry” requirements can only be met when repairs are undertaken in a covered dry dock. The loss in productivity when working in the open in the rains, compared to that in an indoor environment, should also be considered.

A dockyard must have access to the ocean and sufficient depth of water year round…

Workshops

The size of the dockyard and the workforce required is entirely dictated by its defined workload. The workload per ship undertaken by the dockyards has been increasing yearly even though the available capacity and capability of the marine industry in the country has been steadily improving. This trend continues encouraged by the costing model used by dockyards. Unlike a market-based business, costs of capital, reserves for replacement costs and future growth, accident insurance costs, future pension liabilities, taxes, military salaries and pensions are not fully reflected in the overheads. This distortion results in lower overheads helping to feather bed low levels of productivity. In such an environment, expansion of any type of work is usually welcomed since it simultaneously increases the union membership and extends the management pyramid with little need for innovation. Because of such embedded inefficiencies, UK, Poland, Germany, Russia and China amongst others, continue to disband or trim many of their less efficient state owned enterprises or public sector undertakings in favour of the free market.

In addition to the above, dockyards generally account for their capital assets on the basis of historic accounting rather than current valuation. Because of inflation, there is a substantial gap between the two. Most of the private sector firms in the marine industry are relatively new. Their asset valuations are closer to the current values. A comparison of such common jobs in both sectors on the basis of inflation asset valuation and true costing will show that many of the simpler and identical tasks done by firms in the private sector are excellent value for money. Because of higher productivity, such firms have superior returns on capital and lower debt-to-equity ratios. They need to be encouraged. After all, except for North Korea, armies have long since abandoned growing their own food for similar reasons and rely on market resources instead.

Fig. 8: Older Dockyards
Dockyards were initially set up to be centres of unmatched technical excellence and speed specializing in complex engineering of strategic importance. They represented the very best engineering skills in the country that could not be found elsewhere. That historic manifesto needs to be pursued far more aggressively and with greater pride. This can be achieved if dockyards continuously seek more specialised work and improvements in productivity whilst offloading the simpler jobs when there are established multiple alternative local sources available to do them. Hence, repairs by sub-contract to the Original Equipment Manufacturers (OEMs) or repair by replacement should be the preferred route for daily use items that are also commonly used by the merchant navy and the public for which facilities already exist in the country. This long list includes items such as life-saving equipment, galley and refrigeration equipment, standard ventilation trunking, light forgings and machine castings, general purpose computers and their software updates, upholstery, rigging, clothing, standard furniture, canvas gear, small boats, small engines and motors, general purpose fasteners and more.

Red tape, mendacity and cost overruns have often dogged many projects administered in the public domain…

Some detractors may claim that such sub-contract work encourages fraud. With modern technology that is no longer valid. Today, the QA documentation for sub-contracted work can include digital photographs of the defects both prior and post repairs with dimensional details using 3-D laser scans. Also, the application of business intelligence or analytics or data mining of all sub-contractual related transactions on a national scale, can now in real time detect any irregularities which could then be subject to an immediate forensic audit.

With a rational reduction in the workload, a modern dockyard should have at-most sixteen or less highly dedicated main centres that have to cater to the specialised requirements of repair of the hull, propulsion, auxiliaries, ordnance, fire control and navigation equipment of a warship. Drawing data for such repairs at any of these centres and ship-borne worksites should be available from the Central Design Office through a Virtual Private Network. CAD/CAM interfaces, smart pads, cranes and robots should be used extensively and in large numbers, especially in the Machine and Assembly Centre which is usually the largest centre in a dockyard. It would be impossible for any dockyard on a constrained footprint with many legacy buildings and infrastructure of past centuries and carrying a hundred industrial centres to be re-engineered to accommodate the facilities described herein and to comply with the international safety codes of today.

A modern independent dockyard can only operate at peak if it has a well educated and trained workforce with outstanding skills that are appropriate for today’s technology-rich digital environment. Existing entry level education standards and apprentice knowledge requirements will have to be drastically raised to reduce the existing extremely wide difference in education and training between management and workers. Simultaneously, training programs and job descriptions require serious revision. The absence of detailed operating procedures for standard jobs with their accompanying onsite training videos also needs to be addressed. It should not be forgotten that a more skilled technician has to be compensated more than adequately. The resulting increase in wages will, however, be compensated for by demands for much higher output.

Fig. 9: Some Outstanding Ports – 20th Century

Location

A dockyard must have access to the ocean and sufficient depth of water year round to accommodate the deepest draft of the ship entrusted to its care. Nature has imposed certain limitations where such a dockyard can be set up. Fig. 4 shows all the possible locations for such a yard. The local fractal index plays a significant role when choosing a site. This index represents a ratio of the change in detail compared to the change in scale. A 2-D curve with fractal dimension very near to 1, say 1.1, looks like an ordinary straight line but a curve with fractal dimension 1.95 shows many convolutions or bays through the 2-D space. The geological history, fractal and inland chart survey of a coastline must be examined in depth to ensure the best site list is narrowed. Europe, China, the Americas, UK, the Archipelagos of Greece, Indonesia and the Philippines amongst others, are all blessed with coastlines that have very high fractal indices. Port sites there are readily available. These are often located in bays carved out by deep glaciers flowing out to sea or through volcanic activity in mountains of granite that surface during the evolution of the planet. The Indian subcontinent (shown in Fig. 5) is a very special case as its coastline has one of the lowest fractal indices meaning fewer number of short lines are required for an accurate measurement of the coastline between two points. An explanation for this follows.

This may be an opportune time for the nation to direct its naval architects and engineers to pick up the gauntlet…

When the earth formed, the Indian sub-continent was once part of the supercontinent called Pangaea. About 160 Ma (million years ago), rifting caused Pangaea to break apart into two supercontinents namely Gondwana and Laurasia. The Indian subcontinent remained attached to Gondwana until the supercontinent began to rupture about 125 Ma. The Indian plate then drifted Northward across the Equator towards the already established Eurasian plate, at a rate of up to five centimetres per year. The Tibetan plateau and the Himalayan range resulted when the Indian plate climbed the Eurasian plate. This ascent still continues. Fig. 6 is a good representation of those historic events.

As the subcontinent drifted, the only major forces acting on its shoreline were the resultant flow current, the wind and the vast amount of silt being washed down during heavy rains by the rivers into the basin of the Indian Ocean. These forces only helped to straighten the coastlines thus reducing the fractal index. The volume of suspended sediments from the rivers emptying into the Indian Ocean is the highest of the three main Oceans. Nearly half of it comes from the Indian subcontinent alone. Cones of thickness of over one kilometre are found in the Bay of Bengal and the Arabian Sea. A number of old ports located in the estuaries on the West coast have, with time, fully silted up. Lothal and Surat in the Gulf of Khambat are good examples.

An Alternative Strategy

Historically, Mumbai consisted of an archipelago containing a chain of seven islands adjacent to the mainland. In 1850, the islands were linked up and joined by fill brought in by rail from the present suburbs. After the fill, the site can best be described as being at the sea end of a very wide estuary. The narrow end of that estuary at Thane creek near the mainland serves as a run off for the main branch of the Ulhas River which originates in the Western Ghats.

Fig. 10: Sea Walls Make Great Ports

Around 1735, a shipyard, later called a Dockyard was located on the inside arm of the main island at its Eastern edge and modeled as an extension of a prominent private shipyard at Surat. Since that date, within site constraints, this Dockyard has been expanded in ad hoc spurts. History shows that erosion by the sea, migration of river mouths, siltation of ports and harbours are some of the problems common to all natural ports on the coastline of the Indian sub-continent; the siltation rate being even higher on the Eastern seaboard. Additionally, the continued discharge of sediments and solid waste into the Thane creek from drains and construction activities due to the increasing expansion of the city of Mumbai, has aggravated the siltation problem. The removal of the silt is presently addressed by escalating expenditures for maintenance dredging with little or no enthusiasm for a permanent solution. The colour of the Indian Ocean opposite the ‘Gateway of India’ memorial at Colaba in Mumbai vividly shows the problems the port and the navy face.

Today, the country has the technology and model testing facilities to alter that fractal index and provide the navy with a practically silt-free and sea blue, deep water basin for a naval yard at a site of its own choosing. This can be achieved by extending the coast deep into the sea using sea walls, 25 metres wide at base, made of granite faced interlocked concrete blocks or poured reinforced concrete and dredging the enclosed basin to the outside depth. The production of the blocks can be fully automated. Such a sheltered ‘Artificial Bay’, similar to that shown in Fig. 4, can then accommodate a state-of-the-art dockyard covering roughly about six square kilometres with a frontal sea basin of eight square kilometres. The disposal of the dredged silt in the proposed basin should not be a problem. It can be utilised to extend and raise the mainland towards the sea at the basin lip, for block filling and also for the private development of artificial island cities similar to that shown in Fig. 7. Such a dockyard with its attached naval complex would still be relevant and serviceable two hundred years from now. As a footnote, the world’s longest man-made sea wall which dwarfs this proposal is 33 km long and encloses a bay of 400 sq.km.; fifty times the size proposed herein. That record will soon fall when a sea wall 60 km long is completed.

fig. 11: air Bubbler under piers
The shape of any basin and its aspect ratios are critical. Wave energy enters and leaves the harbour basin directly normal to the entrance lines of the wall openings and by diffraction from other directions. Although the wave height distribution in a harbour basin can be predicted by computational fluid dynamics it must, because of the need for accuracy, be verified by precise scale test in a model Wave Basin. Using these tests, the geometry of the basin, orientation of the sea walls and gateway sizes can then be optimally tuned to reduce the wave height and tidal silt under extreme weather.

Silt from the monsoon run-off and sewer refuse on the entire naval site will still occur. However, being an isolated new complex, the flow rate and sediment content into the basin can be completely controlled by improved civic discipline, oversized storm drains, fish ponds, silt traps and sewage treatment systems. The building of an artificial harbour is a proven technology refined through time. Aerial views of such harbors built in Roman times to now have been shown in Fig. 8 to 10. Due to stagnation at piers that berth deep draft vessels, residual sludge will have to be dealt with. This is an age-old problem. Fortunately, this can now be easily addressed using an air bubbler system which can be activated occasionally and synchronised to act in unison with the ebb flow. See Fig 11.

A modern independent dockyard can only operate at peak if it has a well educated and trained workforce with outstanding skills…

Conclusion

Dockyards that meet the requirements suggested with their associated naval complex will allow the navy to have the appropriate up-to-date tools needed to ensure it can maintain a modern fleet at a high operational level for many decades to come. The experience gained during this construction could then be the cornerstone for developing a series of island cities by private developers. Such projects, which also result in peaceful territorial gains and a boost for the economy, would help to absorb some of the many million students who graduate each year.

Clouded by the traumatic experiences of some past projects, the difficulties of such mega projects may appear very formidable to the less experienced. Red tape, mendacity and cost overruns have often dogged many projects administered in the public domain. It will be prudent to avoid a repetition of the same. To achieve this, it is suggested that the project be routed through distinct phases. In strict order, these are – preliminary evaluation of potential sites for a naval complex inclusive of the dockyard, Statement of Requirements, concept formulation and selection, Request For Proposal, selection and final specifications, completed system design, detail design and build and warranty.

It is also suggested that a separate professional team review the Statement of Requirements, the final specifications and the deliverables and warranties required for potential conflicts and misinterpretation. Because of the need for brevity, the role of the Military Engineering Services, National Institute of Oceanography, the State Governments and other concerned agencies have not been detailed herein. Suffice it to say that their expertise, cooperation and goodwill are absolutely essential to a program of such importance. They should at the earliest be incorporated into the project network as willing partners ready to share their expertise. Any project of this magnitude is best executed on a fixed price basis with enforceable penalties for delay. Add on costs, often precipitated by an owner – initiated stream of alterations and additions during construction, can be drastically curtailed through a process of pre-planning, accountability and financial incentives.

We now live in fast changing and challenging times that call for bold solutions. Other maritime nations have already shown similar projects can be done successfully and with breathtaking speed in record time. The modernisation of repair facilities proposed will result in better availability of the fleet which could, with time, lead to a reduction of the number of replacement ships required and thus a reduction of capital expenditures. This may, therefore, be an opportune time for the nation to direct its naval architects and engineers to pick up the gauntlet instead of confining them to a career of constrained mediocrity.

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