Suggestion for a physical-chemical assessment of the sea coastal waters pollution on the basis of the analysis of the examination on the Gdańsk Bay waters.

The study presents the results of physical-chemical examinations of the coastal water of the Baltic Sea, carried out from 1984-1988 on 18 sampling stations located in the region of Gdynia and Gdańsk, and along the Hel Peninsula. The samples were collected weekly from the surface of water in the distance of about 5 m from the shore during 5 years. The results indicated a considerable physical and chemical pollution of the coastal water of Gdańsk Bay. Noted is the absence of the criteria of sanitary evaluation of the sea water regarding its usability for recreation. Mean concentration values of phosphates, ammonia compounds and nitrites as well as BOD5 in the coastal water of Gdańsk Bay were on the average 5-10 times higher than in the water of the open Baltic Sea. If the level of reference is the open sea water, it must be assumed that the coastal water of the Gdańsk Bay is strongly polluted. Useful seems to be the determination of the level of the physical and chemical pollution of the sea coastal water by comparison of certain indices with the values characteristic for open, clean sea or by relating them to the values making the "background" for the sea area examined. There is a need to elaborate evaluation criteria of physical and chemical pollution of sea coastal waters.