Tool - 3Di

Link to external tool

Related to Aspects

Risk assessment
Choose optimal set of options
(possibly) Baseline performance


3Di is an interactive model for water management and can map out water flows and the effects of flooding, heavy precipitation and drought, both for the current situation – for example during heavy rainfall – and for climatological scenarios in urban and rural environments. For example, a ‘water scan’ can be carried out using the 3Di area model, allowing the vulnerable areas in the city during extreme precipitation to be mapped out accurately. In addition, 3Di shows the effects of interventions in water and spatial planning on water management. The area models are suitable for a broad target group, varying from water specialists, spatial planners, operational managers and communications advisers through to disaster coordinators.


The area models are generated automatically from the object database and the raster database by a 3Di specialist. Every water manager has source data and the corresponding software for managing data about waterways, sewers and civil engineering objects. When an area model is produced, data standards are used along with standard management software. The data that is required for the area model is read into an ‘object database’ and a ‘raster database’. A 3Di area model can consist of one or several model layers, namely a:
  1. raster terrain layer (for flooding and precipitation)
  2. raster subsoil layer (for soil moisture content and groundwater) – The soil properties are specified per sub-grid and the soil moisture content is calculated per sub-grid.
  3. 1D open water network layer (for the canal system) – A profile can be given for the canals showing resistance and bed height
  4. 1D sewer network layer (for the sewer system) – Underground constructions can be described in detail using storage height functions
Precipitation and evaporation can be input as well as flooding. In principle, the precipitation uses weather radar images, but it is also possible to add precipitation from weather stations.


A 3Di area model can be used for a desktop study, as an interactive tool in workshops and as part of a system for fire brigade support or high water prediction. The users can play interactively with 3Di. Effects of possible interventions can be visualised in next to no time, providing maximum support for the evaluations. The high level of detail also means that laymen can recognise the situation and ‘non-specialist’ users are also able to come up with ideas and try them out.


3Di is a highly successful co-operative venture, consisting of Nelen & Schuurmans, Detares and TU Delft, who have joined efforts in the foundation called Stichting 3Di. This foundation manages 3Di and is working on further development of 3Di.