Chinese Surveying

Japan has protested against alleged surveillance activities by a Chinese vessel near disputed islands. Japan says it spotted a Chinese ship early on Sunday that was apparently carrying out research in what Tokyo considers its waters in the East China Sea. It says the Chinese ship was surveying an area about 30 kilometres west of Uotsuri Island and left after verbal warnings from a Japanese patrol boat. Japan issued a protest to the Chinese embassy in Tokyo, which said it would check the details of the incident. (read more)

2007-02-06 11:12:24

Riverbed Surveying

Hydromapping - High Resolution Shallow Water Mapping from an Airborne Platform

In order to meet the requirements of the European Water Framework Directive (EU-WFD), authorities face the problem of performing area-wide surveys of all kinds of inland waters repeatedly. Especially for mid-sized and small rivers, a traditional survey approach imposes almost insurmountable logistical efforts and costs. Employing the new airborne hydrographic laser scanner RIEGL VQ-820-G, potential large-scale surveying of a river system is exemplarily demonstrated on the river Loisach in southern Germany, carried out by the company AirborneHydroMapping (AHM) and the University of Innsbruck. By Martin Pfennigbauer, RIEGL, and Frank Steinbacher, University of Innsbruck, Austria. In co-operation with the Bavarian Water... (read more)

2012-03-08 04:33:36

Surveying Lac de Vassivière

Together with the Interdisciplinary Centre for the Development of Ocean Mapping (CIDCO) in Canada, French engineering school ENSTA Bretagne, the University of Ghent in Belgium and the HCU University in Germany conducted an intensive hydrographic and topographic survey training programme at the artificial Lac de Vassivière in France in October 2011. The project lasted three weeks, during which the students were placed in real working conditions and had to face challenging situations, such as surveying in very shallow waters, poor GPS coverage, variable water column conditions depending on time of day and processing large volumes of data in a short... (read more)

2012-07-24 04:44:52

Ice-jam Flood Surveying

The large, poleward flowing rivers of Siberia, such as the Ob River, experience persistent and severe floods when river ice breaks up in the spring. Ice-jams are common on the Tom River, a tributary of the Ob, resulting in a rapid rise in water levels upstream of the jam and submergence of thousands of homes. Furthermore, a sudden breach of the ice-jam releases a flood wave that can cause extensive damage downstream. By Ray A. Kostaschuk, Simon Fraser University, Canada; Dmitriy A. Vershinin; Valeri A. Zemtsov, Tomsk State University, Western Siberia, Russia. Floods in large rivers are caused by a... (read more)

2014-08-12 10:34:55

Remote Hydrographic Surveying System

Staff at Frontier Precision, USA, have been working hard to design and build a safe, affordable and reliable hydrographic surveying system that is simple to use, and easily deployed. The boat uses an RC system that is integrated with a SonarMite high-accuracy echo sounder and a Trimble GNSS receiver which communicate via long-range Bluetooth, with a Trimble TSC3 running Trimble Access. This system provides safe data capture in otherwise challenging hydrographic environments or areas that are too small for conventional boats. In November 2013, one of the boats was used to perform a hydrographic survey of a utility crossing in... (read more)

2013-12-02 04:01:09

Canadian Arctic Surveying

For the third year running James Williams has ventured into the Canadian Arctic with Aquatics to support land and hydrographic survey work for Shell Canada, Shell Oil, Devon, EnCana and Esso. The team of seven, including local Inuit to protect them from the unpredictable wildlife, camped rough through the Arctic tundra river system of the Mackenzie Delta. Using the latest sonar technology in the form of a Ross Sweep system with 6 transducers mounted on a 15m boom, water depths from 5m to less than 1m were consistently mapped in many of the shallow areas that are located at the... (read more)

2007-01-08 03:55:10

Surveying Wrecks around Estonia

As a part of its mission to ensure safe navigation, the Estonian Maritime Administration identifies possible navigational hazards in Estonian waters, including potentially dangerous wrecks. Some of these wrecks, especially those lost during WWII, pose a potential environmental threat because of their cargo and fuel. High-resolution multibeam sonar systems help find and identify such wrecks. Read on for some examples of wrecks surveyed using a Teledyne RESON SeaBat 7125. This article has been brought to you by Teledyne RESON. Dago The steamship Dago was built in England in 1912 as a cargo ship. The ship was taken into use by... (read more)

2017-03-23 09:05:46

Surveying in Fluid Mud

The effects on bathymetry of suspended sediment in the water column

Virtually all ports and channels throughout the world are currently monitored using the now familiar acoustic echo sounder. However, the very parameters upon which these instruments are based are often distorted in suspended sediment, resulting in erroneous seafloor indicators. The author reports on workshop discussions during Hydro 2005. In many of the world’s most important ports and harbours the presence of unconsolidated material suspended in the water column requires the hydrographic surveyor to pay particularly close attention to good survey practices and techniques. The high-frequency pulses emitted by most echo sounders reflect off even a very sparse accumulation of material... (read more)

2008-01-01 01:00:00

Subsea Cable Route Surveying

Planning Challenges

Almost all (99%) international data is transmitted by around 265 subsea cable systems connecting the world. The total length of subsea cables exceeds 1.6 million kilometres, and they can be found as deep as 8,000m. The cables, which can cost hundreds of millions of dollars, must generally be run across flat surfaces of the ocean floor, taking care to avoid coral reefs, wrecks, environmentally and politically sensitive areas and general geological obstructions. Diameters are generally no thicker than an average garden hose. Cable laying is an expensive operation and is a function of the total length of cable, water depths... (read more)

2017-10-30 03:32:44

Surveying the Venetian Lagoon

The world's best-known estuarine lagoon has been of tremendous historical importance in sheltering the city of Venice. It is an ever-changing environment with only 8% covered by land, 12% by open water and the remaining 80% by mud flats, tidal shallows and salt marshes. This geographical setting, hosting complex ecosystems, is influenced by tidal cycles entering through three sea inlets and freshwater and sediment supplied by river influx. The Venice Institute of Marine Science (ISMAR-CNR) is engaged in numerous projects regarding researching and monitoring the lagoon. Monitoring changes to the environment is becoming ever-more important in view of... (read more)

2012-01-23 10:44:08