If the person authorized by the institute needs to enter the real estate of others in the course of the work of the institute, he can enter the real estate of others immediately after giving prior notice to the person using such house or land. However, if there is a reasonable reason to suspect that water is being misused or stolen, in the course of the investigation, prior notice shall not be given when the chairman or the officer of the institute designated by him enters at any time other than the night time from sunset to sunrise.