Visual impact assessment of river regulation structures

The paper presents the quantitative methodology for visual impact assessment of river regulation structures such as non-submerged groins and longitudinal dams. The method integrates LIDAR data, GIS tools, 3D graphic software and 360° panoramic images. Digital Surface Model (DSM) developed on the basis of LIDAR data and imported to 3D graphic software allows one to render images from any location of 3D scene. This feature was used for rendering 360° panoramic images from the perspective of the observers located on the study site in designated with the viewshed analysis area. Renders were verified against panoramic photographs taken during the field inspection. The proposed methodology was tested on two locations of Kostrzyn nad Odrą and Słubice cities where modernization of regulation structures on Oder River is planned. Calculated percentage values of river regulation structures occupying the full field of view of the observer for 25 locations in Kostrzyn nad Odrą and 19 locations in Słubice shows insignificant visual impact. The maximum values of 0.94% and 0.26% for Kostrzyn nad Odrą and Słubice respectively, where obtained. Additionally the visualization method in the form of “Little Planet” projections was presented, which allows for full documentation of the visual impact of the structures on the landscape.

Visual impact assessment of the Istanbul Land-wall

Visual impact assessment studies are reasonably substantial to understand an environment which has different features. The aim of this study is to evaluate the visual impact of the Istanbul Land-wall and contribute to future design/planning stages. For this purpose, the study area was separated into four different spatial usages which are recreational, transportation, agricultural and neglected places. Twenty-four different photographs were taken and a survey was conducted upon an expert and a public sample group. The public survey included four parameters: well-kept, exciting, safety and beautiful scenery. The expert survey also involved four parameters which were coherence, imageability, stewardship and historicity. One-way ANOVA test was conducted to reveal sample groups’ effect on the preferences. The results showed that the average scores of photographs evaluated by public and experts were 11.07 and 9.80 scores respectively. In the public survey, the photograph, has the lowest scores for all parameters, was Photo-11 (P11). Experts’ result shows particularly that historicity is lower than the others although the area is a historical region. Specifically, neglected places obtained lower scores than the other spatial types. Consequently, the Istanbul Land-wall does not have adequate visual quality regarding the selected parameters.