By
Mansoureh Hasanzadeh
Ports and Maritime Organization of Iran, Coasts and Ports Department
The challenge of maximizing dredging efficiency is still remains as a dilemma in port management and brings about unforeseen costs annually. While among many environmental and safety rules which are addressed and executed in marine waters, there’s no exact direction about dumping dredged sediments. It’s obvious that dredging operations to deepening shipping channel and increasing draft should be done temporarily. On the other hands, the dumping of picked sediment (both contaminated and clean) supposed to be done based on comprehensive technological aspects. Whereas, a cost dredging and crucial environmental consequences are worryingly high.Initial surveys reveals that the availability of information on target marine area should be as enough as its need to make big necessary data which should be drawn.
Ports which are located at closed coastal area such as Bays, Deltas, Channels, or at special ones like Estuaries have to do perform more dredging operations. In many cases all these area are sedimentary capable and considered to begeo morphologically breakable. As a results, of marine circulations, reception of much many external streams, low depth, weather condition and bathymetry features, the quantity and quality of sedimentation differ in marine area. The effective factors on movement of sediments are clearly known for marine’ experts. But handling the solution of getting rid of extracted sediments need a fully innovative answer!
As mentioned before, hydrodynamic characteristics and different currents have the most impacts on the amount of sediments loads that is picked up and transferred. So, because of the loading capacity of marine currents, relocation of disposed sediments should be done under a wider pre study. An acceptable site is which one that has the most stability of oceanic currents and deems to have proper depth adjusts to purpose. Therefore, a bathymetry research is undeniable. For example: discharging down to Abyssal plain is completely different from Continental Shelf. The movements of sediments after dumping which occur under many circumstances has a key role in disposal site selection and take serious effects on further applications. This is a controversial issue in area of Persian Gulf.
So, we should track for a perfect answer which obviously results in Persian Gulf characteristics and future management plans. Growing economic in marine industries and then exploitation of much offshore regions due to supporting developing trade (which are aim to bring economic benefits/opportunities) is temptingmanagers to utilize Islands. Therefore, we should seek something that not only help us not to dry shorelines, be cost saving, not damage coastal land scape and make the most chances for developing ports space. Regarding to Iran ports condition along Persian Gulf and increasingly demands for more progression, making use of Islands could be a wise decision. As a clear result, making artificial Islands using extracted sediments from marine activities has more consistency to this discussion.
Hence, to wearing this claim an applicable cloth, first of all, we have to search for suitable points which are perfect beds to growing such Islands in. As operational costs of dredging are inevitable, using the obtained sediments to future utilizations sounds more reasonable. So,after performing a comprehensive site selection study for dumping,preparing the requirements for settlement of manmade Islands is the second step. But what shouldn’t be neglected are putting a purposeful programming and designing steps which are according to next application.
Naturally, these Islands start to make new different ecosystems in around themselves. Hence the first outcome of artificial Islands idea is increasing natural diversity of marine area. Considering these areas are easily broken in one hand, and destructive marine operations in the other hand, new fauna,flora and particular geomorphology are considered as fundamental and fortifying supports.Second consequence of fist outcome is ecotourism’ attractiveness. The Islands will open new doors to national and international economy. Alteration of constructed Islands to Eco-tourism or other commercial centers have another advantages and disadvantages for locals. Maybe on day world needs to make much more of such Islands to settle people and put commercial, industrial centers, have enough airports and terminals, good fields to grow foods and advanced scientific centers. Therefore, transmission of dredged sediments to artificial Islands, except of compensation dredging and dumping costs, will create special opportunities to locals and national economy. But achieving this goal depends heavily on long term management plans which be determined before. The anticipated from an artificial Island will affect all its Islands will affect all its constructive and civil characteristics. Structural stages used material, designing, view, resistance and stability and target size will be different.In Iran, dumping of dredged sediments is still a hot potato in marine management. Is some, cases in Persian Gulf there isn’t enough backshore area due to more port developments, and engineers have no choice to dry shore area for necessary constructions. On the other hand, economy is very dependent on the sea. The numbers of careers are as varied as one’s desires and imagination; recreation, fishing and shipping industry, transportation, even research and non-research ones. Imagine that artificial Islands how affect these jobs?
Negin is a unique Island that is made of dredged sediments while digging channel of Boushehr Port many years ago. Until recent decade, this Island hasn’t been used as a new ecosystem,but based on the Imperative plan to widen current port and the lack of enough area,Negin’s become a single option for urgent development. Today, the Island is going to convert to “Negin Port Complex” which opens up many doors of international economy to Iran economy. Hence, if extracted sediments be laid at exact point, under up to date technical considerations, it will lead us to estimating goals. Then, being an untouched background in the middle of industrial area, closed to infrastructures of developments has a high capacity for attract global trade could grow the early roots of future progresses. This approach leads to increase of Gross Domestic Product(GDP) , economic outcomes, environmental protection and marine based sustainable economy. Although, raising Island from waters, especially from useless materials such as dredged sediments from seafloor is an amazing approach to another kind of sustainable marine development, but its’ not beyond the thoughts if one day mankind desires to build his cities on the new water Islands. Then, new generation of these creatures should be designed and constructed for our children.
We at engineeringcivil.com are thankful to Sir Mansoureh Hasanzadeh for submitting this to us. We are sure this will be of help to others looking to know more about this field.
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