REVIEW OF GERMAN EXPERIENCE ON COASTAL PROTECTION BY GROINS 
by 
Dr. Marcus Petersen 
Dr. Marcus Petersen, renowned German coastal engineer 
and scientist, Director of Water Management and Economy of 
Schleswig-Holstein in Kiel, Germany, published in the periodical 
"Die Kuste" of 1961, under the title 'Das Deutsche Schrifttum 
uber Seebuhnen en Sandigen Kusten", a survey on experience with 
groin construction. The 57-page article evaluates the experi- 
ence accumulated by 120 prominent German coastal engineers and 
scientists as published in 210 bibliographic items which extend 
over a period of 140 years. It offers an interesting insight 
on the opinion and attitude of German engineers toward the his- 
torically controversial and highly disputed subject of coastal 
protection by means of groins, in which not only engineering 
and scientific, but to a great extent economic elements, have 
an important role. The paper by Dr. Petersen has six sections: 
I - Introduction; II - Collection and Evaluation of German 
Documentation on Groins; III - Chronologic Survey of German 
Documentation on Groins; IV - Experience on Seagroin Effect; 
V - Conclusions; and VI - Bibliography. Essentially the en- 
tire article was translated by Otakar W. Kabelac, Engineering 
Division, Beach Erosion Board. The following is an abstract, 
prepared by Mr. Kabelac, of each section of the article. 
I - INTRODUCTION 
The function of sea groins, as a means of protecting sandy shores, re- 
mains even to the present time a controversial problem. The coasts of the 
earth are perpetually changing, the rocky coasts changing to a lesser degree 
than sandy coasts. Natural changes fluctuate in short time intervals around 
a certain base, and vary with location and time. Coastal regions exist, 
which when viewed with regard to long-term prospects, have a tendency to 
silt up, while others tend toward erosion. At the time of observation, the 
tendency for long-term coastal recession may coincide with an equally di- 
rected tendency for temporary fluctuation (as for example, the conditions 
following storm tides); then it is difficult to forecast what development 
of the beach will take place in a long period of time, 
The engineers responsible for coastal construction are confronted with 
this problem more and more. Human interference with the labile equilibrium 
of nature, sandy coasts in particular, became more extensive because of the 
growing demands for coastal developments and protection. Often it cannot 
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