One of the rising issues for the Three Gorges Dam area in China has been flooding. Steep slopes combined with heavy rainfalls have led to increased soil erosion. To solve this problem, the citizens within the impacted areas resorted to long-known methods previously used. These included terracing and vegetation to prevent erosion.
In this particular case, the problem was clearly evident, and dealt with as it occurred. But others use geomatic technologies to classify potential flood areas, thereby enabling mitigation steps prior to damage and difficulties to inhabitants.
Topcon, for example, has recently introduced technologies for measuring landscape topography. Astrium has also launched a new GEO Elevation Product Suite. Lidar has been used for developing topographic products in Kaiapoi & Christchurch. Baomoi reports that Vietnam and France are working on joint projects involving topographic measurement. “Vietnamese Deputy Minister of Natural Resources and Environment Nguyen Manh Hien said the GIS has been applied in Vietnam in agriculture-forestry planning, forest management, archives of geology, topographic and land survey, urban management.”
DTMs are widely used to determine potential flood areas and they are also used to study water channels and areas suitable for drainage related work. Insurance companies depend upon accurate terrain modeling because it helps them to determine which homes, infrastructure and other valuable assets are in or near potentially dangerous areas where floods may arise.
Improved digital terrain modeling and their widespread distribution is helpful for ensuring local regions can contend with flooding and can pursue economic development successfully. Their importance cannot be overlooked, which is why many consider the digital terrain terrain model as a basic foundation step.