The paper presents the results of the research regarding the amount of sewage inflowing by the sewerage system and the amount of sewage brought to the collective sewage treatment plant in Nowe Brzesko with the sanitation vehicle. The analyzed treatment plant is located in the area of Nowe Brzesko town in Nowe Brzesko Economic Area on the left bank of the Vistula River. Domestic sewage from 250 buildings are drained into this object. The analysis of the amount of sew-age was carried out in the period from January 2005 to December 2007. In this period the amount of sewage inflowing and brought in each month was defined in order to compare this amount with the designed one. Moreover, the paper presents the frequency of the defined amounts of inflowing sewage occurrence, as well as the probability of their occurrence. After data analysis, it was stated that the tested object is hydraulically under-loaded. In 2005 the actual amount of treated sewage constituted only 20,4% of the established treatment plant capacity, in 2006 this amount was 22% and in 2007 – 26,7%. In the period of 3 years high irregu-larity of the amount of incoming and brought sewage in each month was ...
