In the final paper of master studies there is analyzed exploitation efficiency of drainage systems. The methods of mathematic statistics were used in the research – filing of the data, clustering, and methods of the graphical expression of the research data. By the research of the efficiency of the maintenance of the drainage in Kaunas district it was determined how the efficiency of the maintenance of the drainage is changing when planting various agricultural plants in the drained land. The structure of the crop according to the specific constitution is fluctuating each year. It is stated that fastest pay off of the invested finances into the maintenance of the drainage in the repaired area, when growing sugar beets or potatoes. The profit got from these plants covers maintenance expenses within one year. Quite good results are got when growing flax. Reconstruction works of the drainage system in Kaunas district were started in 1964. The biggest part of reconstruction was done in 1996 4311ha. Reconstruction works were fast performed until 1999 afterwards because of the lack of the finances these works get slower.