Throughout history, navigation and maps have benefited humans in their journeys and expeditions. Even if humans had their idea about the prospective routes and journeys, maps and related guides had helped them to stay on track, to gauge that they are on the right path or to identify any possible barrier or hurdle along the way. Simply, they make your journeys smooth and convenient. Otherwise, history has seen multiple stories of people stuck in difficult situations because of not having a relevant map or guides along their way.
Just like navigation and mapping required for your town, city or land in general, there is a crucial need for adequate navigation and mapping to maneuver the path and plan the sea journey. There are many industries and professional fields that are associated with sea travel and ocean journeys like fishing, logistics, oil extraction, etc. And comparatively, humans can still afford to get distracted on land rather than the sea. Sea can be a dangerous companion on the way if you are not routed clearly. Therefore, the sea is also evaluated and navigations are created through an extensive procedure called Hydrographic Surveys. It sounds quite technical, but an interesting knowledge to grasp. Its main purpose is to measure and determine the distance and properties of the seafloor, related water bodies, and land areas adjacent, which helps in apparent navigation but also to determine the condition of the area of navigation. For example, it is vital in advance or while on the journey to know that whether the area underwater is safe to travel, for fishing or oil exploration beneath.
PROFESSIONALS INVOLVED IN THE SURVEY:
It is an extensive and expert field, people involved in it are not generalists, but there is no such thing as one ‘Hydrographic Survey Expert’ but there are many people involved covering multiple tasks in the game. It is a kind of team project where some people are responsible for sounding procedure, some take care of data gathering and refinement, and some maritime cartographers are involved in data interpretation and finalization.
Normally, there are many governmental and private agencies and companies that conduct hydrographic surveys for multiple objectives. Every company needs to get proper licensing and permits before starting its services. You can simply find such companies or services by searching online and Hydrographic Survey Australia stands out for its sophisticated services and reliable results.
WHAT’S THE PROCEDURE?
One slight understanding before getting into the process is the difference between Hydrography and Hydrographic Surveys. They are not the same phenomena. Hydrographs relate to the measurement of through and flow of water, whereas the Hydrographic Survey deals with the ‘surface’ underneath the water. Hydrographs can be simply done on a local pond or river, and it is comparatively an easy task with regards to the Hydrographic Survey, which as discussed is quite a daunting task.
Previously, measurements were taken manually by dropping equipment and carrying back to take the readings. Nowadays, there are many advanced approaches and equipment is taken into consideration like Sonar Equipment (which is an acronym for sound navigation ranging). Sometimes, low flying airplanes are also being used, depending on the area being examined. The procedure to gauge and measure depth below is called ‘Sounding’. And the typical basic equipment used in modern Hydrographic Surveys is Sounding Boat, Sounding Pole, and Lead Line.
Typically, through sounding Boat, sonar equipment throws sounds to the beneath surface of the seafloor and get it bounced back to the vessel, and then the sound properties and echo are studied and measured to determine the depth of that particular area range. Numerous sound scans and measurements are required to be taken per square foot or square meter, therefore, it takes a heck lot of time.
And the process is not done yet, it is just data mining. There is a whole phase of data processing and interpretation is to be done on the data generated. Generally, an outrageous amount of data is generated and not all are of use, as in some attempts sonar equipment fetch bad scans. Therefore, a significant effort of data filtration is done to make the data ready for interpretation.
After that, Maritime Cartographers adjust the data to eliminate and extrapolate the results to account for seasonal variations, weather changes, tides, wind speed, etc. to determine correct and precise navigation and mapping for general and specific usage.
Hydrographic Surveys are used for multiple purposes and in numerous ways, the final product focuses and differs from others. For example, Pre-Seismic Hazard Clearance Survey Utilizes for assurance of unchartered obstruction for future towed streamers, whereas River Surveys are used for checking out the underneath area before mineral resources extraction and transport to the nearby shore. But it is vital to understand and know the details and mechanics of basic Hydrographic Survey conduct.