Portete Bay is located on the Discharge Guajira, exactly on the east side of Guajira between the 12°14'N and 71°52'W. It has a surface of approximately 80 Km2 and a narrow mouth of communication with the sea. It counts on with one of the country's largest coal-carrying ports with an annual arrival average of close to 400 international traffic ships. In view of the importance that this national port represents, the raising of the base line of the zone, whose main purpose was to determine the behavior of three components in the bay (physicochemical, biological and microbiological) was carried out; at the same time, the sample taking of ballast water from 25 tanks of ships which had arrived in the port during the six monitoring campaigns, between March and November, 2007 to which the assessment of the same parameters was undertaken. We determine that the 12% of the analyzed tanks were above the International Maritime Organization (IMO) permissible limits for E. coli (250 CFU/100mL); for Enterococcus, 8% of the ships is above the limit (100 CFU/mL). Based on secondary information gathered in the zone, only physicochemical and biological type analyses have been carried out. This way, they become a preliminary diagnosis tool of this component in the zone.