Duties of surveyor. Survey-register.

It shall be the duty of the surveyor appointed to make a survey of any river to note upon the charts thereof all cultivation existing or ordinarily carried on, and all groynes, buildings, plantations, constructions or obstructions within the surveyed limits of the said river and to prepare a register to be styled the survey-register, containing the above particulars. The surveyor shall also mark upon the charts the ordinary channel as it exists at the date of the survey so far as it can be ascertained.