Hydrographic Surveying

Definition:

Objects
of Hydrographic Surveying:

1. Measurement of
   tides for sea coast work E.g. construction of sea defense works, harbors
   etc, for the establishment of leveling datam and for reducing sounding.
2. Determination
   of bed depth, by soundings
• For
  navigation
• Location of
  rocks, sand bars, navigation light.
• Fro location
  of under water works volumes of under water excavation etc.
• In connection
  with irrigation and land drainage schemes.

3. Determination
   of direction of current in connection with
• The location
  of sewer any pipe or channel that carry waste water out falls.  
• Determination
  of area subject to silt and seour the eating of the place.
• Fornication
  purposes.
• Measuremenment
  of quantity of water and flow of water in connection of water schemes,
  Power scheme and flood controls.

Why
we need Hydrographic Surveys – Uses & Applications of Hydrographic Survey

1. Offshore
   engineering and the shipping industry have continued to expand.
2. Drilling rigs
   (extracting oil, gas etc from deep sea) locating up to 125miles
   offshore, search for resources particularly oil and gas.
3. Offshore
   islands are constructed of dredged material (to bring material form some
   where and dump there) to support marine structure.
4. Harbor depth
   up to 80 is required to accommodate larger ships and tankers.
5. Containerization
   has become an efficient and preferred method of cargo handling.
6. The demand for
   recreational transportation ranges form large pleasure cruise ships to
   small sail bonds.
7. Cruise ships
   to small sail bonds. Hydrographic surveys are made to a quire and
   present data on oceans, lakes and harbors. It comprises all surveys made
   for
• The
  determination of shore lines, soundings (measurement of depth below the
  water level) characteristics of bottoms, areas subjected to Suring and
  silting, depth available for navigation and velocity as well as
  characteristics of flow of water.
• The location
  of lights rocks sand balls, buoys ( anything that floats on the surface
  of water)

Establishing Horizontal and Vertical Controls (Click Here)

Horizontal Controls:

Vertical Controls:

River Surveying

Sounding Surveying