Tool Name	Fill Minima
Tool ID	8
Library ID	ta_preprocessor
Version	2.0
Author(s)	Justus Spitzmüller (c) 2025, Neil Flood (c) 2015, Richard Barnes (c) 2014

Description

This tool performs basic sink filling on Digital Elevation Models (DEMs). It identifies and fills local depressions (sinks) to ensure continuous flow paths across the terrain surface. Note: this tool does not carry out a full hydrological correction â€“ it only addresses depressions and does not modify flat areas, resolve flow directions, or enforce hydrological consistency beyond sink removal.

The tool accepts a DEM as input and returns a version with filled depressions. Optionally, users can define a fixed boundary value to control how edge/boundary cells are initialized during filling.

Recommended Usage:

Choose Soille & Gratin for (scaled) integer DEMs.
Choose Barnes et al. for floating-point DEMs.

References

Barnes, R., Lehman, C., & Mulla, D. (2014): Priority-flood: An optimal depression-filling and watershed-labeling algorithm for digital elevation models. Computers & Geosciences, 62, 117-127.

Soille, P., & C. Gratin (1994): An efficient algorithm for drainage network extraction on DEMs. . Journal of Visual Communication and Image Representation. 5(2): 181-189.

Python Fmask

RichDEM

Parameters

Name	Type	Identifier	Description	Constraints
Input
DEM	grid, input	DEM	Digital Elevation Model
Output
Filled DEM	grid, output	RESULT	Processed DEM
Options
Method	choice	METHOD		Available Choices: [0] Auto detection by input [1] Soille & Gratin 1994 [2] Barnes et al. 2014 Default: 0
Set Fixed Boundary Value	boolean	BOUNDARY		Default: 0
Boundary Value	floating point number	BOUNDARY_VALUE	The boundary value will be scaled by the scaling factor of the input.	Default: 1.000000