What is a Harbor and their Types in Water Transportation
What is a Harbor?
A harbor is a partially enclosed water surface with greater depth and this area is not effected by the action winds or waves. It is generally situated along sea shore or river estuary etc. to promote navigation through sea.
Requirements of a Harbor
The basic requirements of a harbor are:
- Sufficient depth should be available for the draught of ships using the harbor.
- Anchorage should be sufficient in the bottom area of harbor during high wind times.
- Protection against waves should be adequate.
Site Selection for a Harbor
If natural formations of harbor are not available then it is essential to build artificial harbor. But the site selected for a harbor should be based on some important factors such as:
- Marine conditions should be mostly favorable without any disturbances.
- The foundation soil or sea bed is properly checked whether it is capable to bear breakwaters against wave and other forces.
- If there are Natural formations like mountains or island, then it is better to select a site nearer to that area.
- Site should be economical and construction material should be easily available.
- Water should be fresh without any pollution.
- Surrounding area should be developed with factories and industries, then exports and imports of goods will takes place highly.
- The harbor should be easily reachable.
- The area of harbor should be large. Generally, it is decided on the basis of accommodation for number of ships.
Classification of Harbors
Harbors are classified into different types based on different conditions such as:
- Safety required
Classification of Harbor based on Safety Required
The requirement of safety or protection classified the harbor into:
- Natural harbor
- Semi natural harbor
- Artificial harbor
Natural harbor formed naturally by the protection of mountains, bays, islands etc. and are in use since long time. So, development in terms of population, geographical features, etc. are rapid in natural harbor regions.
Semi Natural Harbor
Semi natural harbors are also formed naturally, but sometimes at the harbor entrance manmade constructions are required for more protection against winds and waves.
Artificial harbor or man-made harbors does not contain any natural protections and these protections are built artificially which are called breakwaters. Breakwaters are the structures which prevent the inside water from storms and waves and keeps the inside water still.
Types of Harbors based on Location
The harbors classification based on location are:
- Sea harbor
- River harbor
- Canal harbor
Harbor situated along sea shore is termed as sea harbor. Sea ports are of very large area and loading and unloading of goods also done in larger quantities. Different countries are connected by these ports.
River harbors are constructed in the rivers which finally connects to sea. So, these enable the navigation inside a country from noncoastal areas.
Canal harbors are also similar to river harbors but a canal is connected to sea through a major river.
Types of Harbor based on Usage
The harbors are classified into five type based on usage as follows
- Commercial harbor
- Fishery harbor
- Military harbor
- Marine harbor
- Harbors of refuge
Commercial harbors are those where loading and unloading of cargos are done. Commercial harbor requires larger area for speed up the operations and it is the busiest among the others.
Some commercial harbors are limited to loading and unloading of single commodities like coal, crude petroleum etc. only. The repair works can also be carried out here but they should be quick.
Fishery harbors are specially meant to cargos carrying seafood or aquatic animals. They are always opened to fishing ships for loading and unloading. For preserving the sea food sufficient space is provided near harbor.
Military harbors are used as naval bases, where war ships are rested while there is no work in the sea or during repair works. No other private ships should not enter this without permission.
Some large military naval vessels can carry aircrafts so, very large area of harbor is required because of large vessels.
Marina harbors are small harbors where moorings are provided for yachts and small ships. They are not suitable for large cargos. The boats, ship repair works, fueling are done in this harbor. For transferring trailered boats into the water slipways are provided at the marina harbors.
Harbors of Refuge
A large area harbors which are useful to shelter the ships during emergency situations like storms or any other natural calamities.
Harbors of refuge are constructed with large entrance and they are easily accessible. They provide good Anchorage to the vessels against storms and tides.