This paper describes the photogrammetric 3D modelling of complex buildings using low-cost automatic image matching (AIM), consumer-grade digital cameras and low-altitude imagery. To verify the potential of this method, it was applied to the documentation of a specific case: the towers and roofs of the Cathedral of Santiago de Compostela in Spain, a UNESCO World Heritage Site. The design and development of a mechanism for coping with the elevation, based on telescopic masts, was essential. Models, orthophotos and plans have been obtained to determine and rigorously measure the geometry involved. Thereby it was possible to accurately record the materials and decorative elements based on the restitution of the granite stones. Furthermore, close range photogrammetry made the analysis and quantification of the inclination of the south tower possible.

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Temperature variation can promote physico-chemical and microbial changes in the water transported through distribution systems and influence the dynamics of biofilms attached to pipes, thus contributing to the release of pathogens into the bulk drinking water. An experimental real-scale chlorinated DWDS was used to study the effect of increasing temperature from 16 to 24°C on specific pathogens, bacterial-fungal communities (biofilm and water samples) and determine the risk of material accumulation and mobilisation from the pipes into the bulk water. Biofilm was developed for 30 days at both temperatures in the pipe walls, and after this growth phase, a flushing was performed applying 4 gradual steps by increasing the shear stress. The fungal-bacterial community characterised by Illumina MiSeq sequencing, and specific pathogens were studied using qPCR: Mycobacterium spp., Mycobacterium avium complex, Acanthamoeba spp., Pseudomonas aeruginosa, Legionella pneumophilia, and Stenotrophomonas maltophilia. Sequencing data showed that temperature variation significantly modified the structure of biofilm microbial communities from the early stages of biofilm development. Regarding bacteria, Pseudomonas increased its relative abundance in biofilms developed at 24°C, while fungal communities showed loss of diversity and richness, and the increase in dominance of Fusarium genus. After the mobilisation phase, Pseudomonas continued being the most abundant genus at 24°C, followed by Sphingobium and Sphingomonas. For biofilm fungal communities after the mobilisation phase, Helotiales incertae sedis and Fusarium were the most abundant taxa. Results from qPCR showed a higher relative abundance of Mycobacterium spp. on day 30 and M. avium complex throughout the growth phase within the biofilms at higher temperatures. The temperature impacts were not only microbial, with physical mobilisation showing higher discolouration response and metals release due to the increased temperature. While material accumulation was accelerated by temperature, it was not preferentially to either stronger or weaker biofilm layers, as turbidity results during the flushing steps showed. This research yields new understanding on microbial challenges that chlorinated DWDS will undergo as global temperature rises, this information is needed in order to protect drinking water quality and safety while travelling through distribution systems.

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Photogrammetry is a commonly used technique in three-dimensional image-based modelling for cultural heritage documentation. Three-dimensional image-based techniques that combine close-range photogrammetry and automatic image matching are presently attracting a great deal of interest. This paper evaluates the feasibility of the application of photogrammetric three-dimensional modelling of an archaeological site with close-range automatic image-matching software and a consumer-grade digital camera. In order to correctly model upward-facing surfaces using this technique, the photographs were taken from the air with the camera in low-oblique position. A mast pole was used as camera platform to obtain low-altitude imagery. To verify the usefulness of this method it was applied to the hill fort 'Castro de Formigueiros', located in Lugo, Spain. In this case, low-cost automatic image-correlation photogrammetry has proved to be a powerful, cost-effective and versatile technique for the documentation, analysis and cultural dissemination of archaeological mapping. The mast used is inexpensive, easily transported and handled on site, and allows oblique photographs of the ground and wall-tops to be obtained at distances similar to photographs of vertical wall faces taken from the ground. As a result, the resolution and accuracy of the point clouds of all the surfaces of the final model are similar. Given the geometric peculiarities of hill forts (the occupied surface area, height, volume and distribution of the objects) and the relief (they are generally located in areas difficult to access and often on high ground), the mast is particularly suitable for photographing low-altitude imagery at archaeological sites, as the final accuracy of the three-dimensional model demonstrates. The tools that have been applied to the final digital model of the hill fort show the information analysis potential that can be obtained for archaeological work.