Enhancing the Fire Dynamics Simulator for Modeling Wildland Urban Interface Fires

The Coeur d’Alene Tribe Information Technology – Geographic Information System (GIS) Program has received a three year grant from the United States Department of Commerce National Institute of Standards and Technology (NIST) to enhance the Fire Dynamics Simulator (FDS) developed by the Building and Fire Research Laboratory division of NIST.  The FDS is a computation fluid dynamics model of fire-driven flow designed to synthesize fire behavior, heat transfer, and smoke dispersion in a 3-Dimensional simulation.  This model has traditionally been used to simulate structural fires and developers of this model want to apply it to the Wildland Urban Interface (WUI).  This project has several aspects and includes:
• providing the FDS modeling program with modeled and surveyed data gathered, acquired, or derived by the Coeur d’Alene Tribe GIS program;
• identification of a parsimonious data set that contains the minimum data inputs to run FDS in the WUI;
• development of an Environmental System Research Institute (ESRI) geodatabase schema and populated geodatabase containing inputs necessary to run FDS;
• developments of applications linking the FDS program to the ESRI GIS platform;
• collection of ground data for verification and model input;
• testing the differences in FDS outputs between modeled and surveyed data;
• testing the applicability of running FDS over large areas and;
• some level of model validation. 

Currently, the data used as inputs to the FDS have been lab or sample data.  The provision of modeled and/or surveyed data to the FDS development group might allow for better implementation and testing of the model to real-world situations.  The Coeur d’Alene Tribe will be collaborating with the FDS group to determine the minimum necessary inputs to run FDS in the WUI.  The modeled data will primarily be derivations of Light Detection and Ranging (LiDAR) data along with high-resolution multispectral imagery.  The combination of this data will allow for the creation of model inputs that might include but will not be limited to:
• Bare Earth surface elevations;
• Building foot prints and heights;
• Roof types and slopes;
• Road and other fire barrier surfaces;
• Tree stem locations and diameter at breast height (DBH);
• Vegetation type.

Surveyed data will come as a result of previous data gathering efforts conducted by the Coeur d’Alene Tribe and new surveys conducted as part of this grant.  The existing surveyed data consists of surveys on structures conducted during 2002 and 2003 within the reservation boundary and Benewah County, collection of vegetation and forest fuels in 2004 and 2005, and ongoing development of spatial databases of roads, railroads, and other man-made features.  The structure surveys followed protocols set forth by the National Fire Protection Agency detailed in form 1144.  The vegetation surveys followed FIREMON protocols (http:/fire.org/firemone/sampmeth.htm).  In addition, new surveys will be conducted as part of this grant, which will result in detailed spatial databases of the inputs necessary to run FDS as well as providing ground-truthed data for the modeled results.  A schema will be developed for an ESRI geodatabase that will serve as the standard for containing data inputs necessary to run FDS from a GIS environment and both the modeled and surveyed data will be stored in an ESRI geodatabase following this developed schema.  The combination of all of the above data will allow for testing of the differences between FDS outputs from modeled data and surveyed data.  This will help determine the necessary level of data collection to run FDS and the practicality of utilizing FDS as a land management tool.

The linkage of the FDS to a GIS will facilitate the creation of FDS input files from GIS datasets as well as transfer of outputs of FDS to an ESRI geodatabase.  The creation and storage of many FDS input datasets will occur in a GIS making it logical to develop applications to allow for creation of FDS input files within a GIS.  GIS also provides a mechanism to analyze and display spatial data.  Consequently, the development of applications to allow for viewing and further analysis of FDS outputs in a GIS environment will prove useful.  The ESRI GIS platform will be used as the software to run these developed applications.  The ESRI GIS platform while being the software used by the Coeur d’Alene Tribe is also the GIS platform used by most federal, state, and local government agencies that would ultimately be using the enhanced FDS model.    

For any model to be applicable for real-world applications a validation process must occur.  Validation of the FDS as applied to the WUI is a challenging endeavor and might prove difficult if not impossible to conduct.  The FDS has undergone a considerable amount of validation work for the purpose of predicting transport of heat and smoke from a fire but the challenges involved with validation of the FDS in the WUI go beyond this type of validation and involve allowing fires to enter into the canopy of trees and burn structures; two prospects that could result in dangerous situations.  Nonetheless, before this model can be used with any degree of certainty by land managers some form of validation, whether it be qualitative or quantitative in nature should occur.  The NIST group has expressed interest in this validation and might be able to provide funds to build modest structures and have these burned in a prescribed manner by the Coeur d’Alene Tribe Fire and Fuels program. 

The resulting calibrated and validated model might allow for the viewing of structures in a different light by the FDS program.  Results of model runs from the calibrated and validated model could provide information to develop a fuels coding system for structures based on there physical characteristics.  This might result in a new data type for the FDS program and ultimately a more predictive approach to understanding fire dynamics in the WUI.  The enhanced model developed as part of this project will ultimately be made available for public use primarily intended for use by fire planners and fire suppression groups nationwide to gain a better understanding of potential fire progression for both individual structures and the community as a whole. 

To view more information on this project please download the powerpoint slides by clicking here.

To view the report from the first three years of the project please click here.