The basis of hydrographic network 1: 50000 is a project carried out by joint order of the Ministry of the Environment (DMA) and the Catalan Water Agency (ACA). The aim of this project is to obtain digital databases and GIS network watershed of Catalonia for scales 1: 50000. The primary source of information for the elaboration of this theme was based hydrographic network base topographic 1: 50000 (BT-50M v3.0) was defined criteria and topographic database drainage basins, for what has become a task of densification and homogenization. It has kept the artificial network but has not been taken into account in generating basins, and in the case of natural drainage network has added sections connection guarantee continuity of it. This coverage corresponds to the selection of the 0 degree axis of the base network of rivers (xarxa50m), adding those areas corresponding to the selection made so that all points of Environmental Control (Inspection and Control), it is referenced on the same network. Only display areas corresponding to the basins of Catalonia.

Allows visualization and query vector data and information associated alphanumeric Networks Hydrological Environment Control, as defined in Directive 2000/60 / EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy in the form of networks.

Information regarding an area exposed to an avalanche. Mapped based on analysis of the terrain and of signs that avalanches leave in their path, mainly, in forests. In Avalanche Zones, avalanches occur frequently and are of different sizes. Avalanche Zones have been systematically mapped throughout the region. They are shown in orange. There are two types of Avalanche Zones: zones where avalanches usually follow the same path, shown in orange, and zones where avalanches usually follow different paths, shown in pale orange.

: Information regarding an avalanche observed in the past. Mapped based on a survey of inhabitants of the area where the phenomenon took place. The boundaries shown are based on the explanations given by the witnesses consulted. Information is usually taken from Avalanche Zones close to inhabited areas where avalanches have historically interfered with human activity. For this reason the majority of the information is found around these zones. They are shown in purple. Cartography often maps only the avalanche arrival zone, as the descriptions usually refer to their extent and the damage caused.

Information regarding an avalanche observed recently. Mapped based on direct observation of the event or observation following it. The information is obtained based on the nivometeorological observation network, rescue groups, countryside wardens, mountain guides, and ski and mountain resort personnel. In the event of important episodes and accidents the IGC technicians also gather information. The elements mapped mainly include the extent to which avalanches affect populated areas, roads, ski resorts and people who carry out mountain activities. Data began to be gathered in 1986. It is shown in blue.

Inventory of defence structures built to reduce the risk of avalanches. Single and lineal structures are documented, such as artificial avalanche release systems, road barriers, breakers, deflection structures, retention nets, screens, wind baffles, deflectors, rigid and flexible barriers, retention walls, reforestation and controlled areas.