This International Standard specifies methods of determining the position of hydrometric boats with respect to known points on the banks of rivers or estuaries. It applies to conventional surveying techniques and, in recognition of the availability of more sophisticated equipment, describes the principles of operation of currently available electronic positioning equipment. This International Standard does not cover the requirements for position fixing that occur in large scale hydrographic surveys such as those conducted on oceans.
GSO ISO 6420:2015 history
2015GSO ISO 6420:2015 Liquid flow measurement in open channels -- Position fixing equipment for hydrometric boats