What must not be done on the coast? (Tips to coastal Engineers and scientists)
The Methods one must not do on the coast are called “4+1 methods”.
They are:
1. Boulder dumping or arranging
2. Wall Construction
3. Concrete blocks heaping or arranging
4. Filling the beach with sand, is called beach nourishment.
The “+1” is a harmful method. It is to facilitate river erosion.
The first three methods are bounces of waves. They energize the coastal waters to erode further that damage kilometers of the coast.
The sand filling confuses the coastal stretch though with mild damages. In addition, the money spent is wasted. For, coast recovery is productive and has payback with many professions.
1. Boulder dumping or arranging boulders
Figure 1 Arranged Boulders
Boulders arranged to stop coastal erosion is harmful to the coast. They bounce the waves. The coastal waters are energised to harm the coast directly fronting and extends kilometers along the coast.
it is very intricate how the process continues. Firstly, the biology in the boulderd stretch is ruined. it is difficult to imagine that the biology thrives.
Secondly, the coastal growth is thrashed from bottom, sides and top. The present day coastal scientists are not aware that a coast grows under natural conditions though the sea level rises. It could be clearly seen beyond any doubts at calcareous as well as at volcanic and granitic (metamorphic) atolls. Provided the stretch is not disturbed by humans. "Waves wash ashore materials from the sea. Even wrecked ships. For, waves always go towards coast.
2. Construction of a wall or a platform on the coast
Very harmful
A wall or platform on the coast is very harmful because they too bounce the waves. Bounced waves energise the coastal waters. it appears that it weakens the coastward bound waves. it happens, too. That is possible when the waves meet frontal. It is extremely rare. The collision of coming and going waves are in an angle. The angular collisions have resultant. the resultant get a resultant with another wave. and continue. It happens that the resultant increases to 300 % or more. and when they thrash at a distant from the walled coast it is a severe damage. Besides, it whirls the seabed and sends the sand else where and deposit the sand.
3. Concrete blocks heaping or arranging
Prefabricated or poured directly or cement packets arranged Concrete works are common in regions where boulders are not found. Mostly in Calcareous atolls. But it is practised also in countries like Sri Lanka.
The damages are same as the walls and boulders. they energise the coastal waters to be harmful.
The harm had been since centuries. But, unfortunately, only a few scientists were aware of it and mentioned. But due to political reasons, the planners had no heed. And stubbornly promoted the methods. Now, in future the coasts must be refurbished. With a new doctrine. The coastal stretch is the most versatile stretch in a country for agriculture, protein production, transport systems and perennial tree cultivation. One should not neglect the health force from the coastal region.