Access to water is essential for human life and the need to control the water infrastructure has always existed. Different types of dams have been built to control water flow in rivers and other waterways. However, it was not until the early 1800’s that dam construction was developed into a science. The conditions for this were increased knowledge of hydrology and solid mechanics. Today, there are three main types of dams made of earth, stone or concrete. Whatever material is chosen for a particular dam depends on the geological, topographical and climatic conditions.
It is estimated that there are more than 50, 000 dams higher than 15 meters in the world. The total number of dams of different sizes is very large and in China, there are around 87,000 dams. Approximately 85 percent of all dams, reservoirs and dikes were built 30 to 50 years ago, and many are in need of renovation. In addition, dam construction is ongoing in the developed world and in emerging countries such as China and Brazil.
Unfortunately, dams have burst throughout history and the consequences for humans and the environment have been very large. The risk of damage to small and medium-sized dams is highest because they are often located in remote areas that are difficult to access and difficult to monitor. The Swedish company Hexagon has recently developed an integrated system that monitors operation and safety of dams.
The Hexagon hydrology solution H2O (Hexagon Hydrology Overall Solution) is a comprehensive system for water infrastructure. It supervises the operation and safety of dams and reservoirs. In emergency situations, the system can secure the surrounding areas and communities.
The system consists of sensors and techniques for monitoring and includes Global Navigation Satellite Systems (GNSS) and scanners, as well as technologies for the management of emergency and surveillance solutions. Monitoring, which takes place in real time, reduces the risk of disasters and incidents. The system sends early warning signs and provides decision support for possible rescue.
A strategic partner for Hexagon on dam safety is the Changjiang Institute of Survey, Planning, Design and Research (CISPDR). The institute constructed the Three Gorges Dam on the Yangtze River in China, which is one of history’s biggest dam projects. For Hexagon, it all started with a pilot project at the Lushui dam, which is part of the Three Gorges Dam. The owners of the Lushui dam faced a variety of challenges because the dam was old and lacked a risk-based supervisory system. There were also gaps in emergency preparedness.
For Intergraph, a company within the Hexagon Group, the Lushui dam was an excellent pilot for testing the installation of sensors, software and other equipment to manage the potential risks such as natural disasters, hazardous situations caused by humans, as well as risks arising from deficiencies in the dam structure. The development started in 2010 and the result was a management system for water infrastructure that consists of three main components. The pilot system is now replaced by the operating system and Hexagon expects the completed modules in H20 to be installed at Lushui.
In addition, Intergraph is joined by other Hexagon companies – Leica Geosystems and Z/I Imaging – to develop the H2O solution. The system provides the ability to both protect the dam and the people, property, ecosystems, roads and other infrastructure that are in the vicinity. H2O includes a number of modules that include:
- Operation and maintenance of water infrastructure.
- Risk analysis and risk management.
- Education and training.
- Recording of incidents and management of emergencies.
- Reconstruction and dissemination of knowledge and experience of incidents and accidents.
The core of the management system is the ability to combine and utilize all the information that measuring instruments, sensors, satellite-tracking systems (GIS), video cameras, weather radar and other technical equipment generates.
Altogether H2O includes 12 different modules. Here are some of the modules in the management system:
Smart H2O Solution Dashboard
The operator of the dam could use a Web browser to quickly analyze the situation in real time based on instrument readings and geospatial views. The operator is warned when the measurements from the sensors deviate from a pre-defined limit, and the system provides information on current and historical data. The geospatial views in 2D and 3D makes it easy for the user to see where the events/deviations are taking place, where the resources are, how the fixes are performed and where the sensors and cameras have been placed. By clicking on the camera icon, the operator can see the places in and around the dam where the video cameras have been installed and follow developments.
Smart H2O Mobile
The mobile application is suitable for inspectors who are responsible for assessing the status of dams and safety and makes it easy for them to compile inspection reports for the authorities. The base is a combination of electronically generated information (sensor values) and information obtained through the visual inspection of the dam. Smart H2O Mobile also facilitates planned and emergency maintenance of dams and similar facilities. All current and historical sensor readings are stored in one location and are available through Smart H2O Mobile. A mobile user can quickly see the latest reading from a particular sensor or multiple sensors and historical values for a date or a time interval in a graphic format.
Great need for monitoring
Infrastructure systems for water provide many opportunities for humanity but also create significant risks. Estimates indicate that over the next 25 years, investment in the order of USD 400 billion will be needed to maintain and repair dams, river levees and other structures. Otherwise the risk is obvious that can result in significant financial responsibility and high environmental impact.
The dam management system H20 makes it possible to remotely monitor very large dams like Lushui in the Three Gorges Dam in China, but also to monitor the status of remote and inaccessible places. According to Hexagon, their system is unique and the Group sees great potential on the global market.
The article was published in December 2013