PURPOSE: To utilize each element effectively and rapidly when required by providing address for each element and determining each set of elements as the first overall element when roughly common information is present in each of more than one set of elements composed of multiple elements similar to each other in each element.

CONSTITUTION: A tunnel 1 as the first overall element is composed of tunnels T1 to T3 as elements similar to each other and each element has roughly such information as common to each other. Similarly, connection #2, pump 4, and valve 5 are determined. In addition, water delivery means 6 as the second overall element is determined. When various types of information is utilized, the required min. common information held by an objective element is obtained in accordance with the address for the objective element first, and the common information held by the first or second overall element to which the objective element is grouped is obtained. Further, the common information held by each element of upper and lower rank in the hierarchy of the objective element and each first and second overall element to which the respective elements of upper and lower rank is grouped can be obtained.