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Visualizing Ecosystem Land Management Assessments (VELMA) Model - 2.0

Version 2.0 – Addresses engineered and natural applications of green infrastructure for reducing nonpoint inputs of nutrients and contaminants


VELMA can be used to help improve the water quality of streams, rivers, and estuaries by making better use of both natural and engineered green infrastructure (GI) to control loadings from nonpoint sources of pollution. It is designed to help users assess green infrastructure options for controlling the fate and transport of water, nutrients, and toxics across multiple spatial and temporal scales for different ecoregions and present and future climates.

VELMA also addresses GI maintenance and longevity to predict how once-effective riparian buffers can fail, depending upon contaminant loads, soil properties, changes in climate and other factors. VELMA was designed for use by communities, land managers, policy makers, and scientists and engineers.


  • Compare the effects of GI and climate scenarios on water quality and associated co-benefits and tradedoffs for other ecosystem services.
  • GI applications for essentially any region and set of conditions.
  • Quantify co-benefits of GI practices, specifically to quantify tradeoffs among important ecosystem services – that is, the capacity of an ecosystem to provide clean water, flood control, food and fiber, climate (greenhouse gas) regulation, fish and wildlife habitat, among others.
  • Use as a common framework to compare GI strategies across ecoregions, habitat types and biophysical conditions.


File Name Description
VELMA 2.0 Model (ZIP)(8 MB) Zip file for version 2.0 of VELMA. Download the zip file to your computer and unzip. Contents of this zip file include the VELMA executable software, supporting tools, and example green infrastructure applications.
VELMA 2.0 User Manual (PDF) Learn more about how to download and use VELMA in the complete guide for operating VELMA v2.0.
VELMA 2.0 Quick Example (PDF) A condensed version of the complete User Manual. This will guide you through a quick example of how to start VELMA and run it for a pre-configured set of input files and parameters located in the zip file.
JPDEM User Manual (PDF) The VELMA model requires a Digital Elevation Map (DEM) for any simulation it runs. Use the JPDEM to prepare DEM data for use by the VELMA simulator.
VELMA 2.0 Fact Sheet  Two-page summary of VELMA 2.0 (EPA/601/F-16/001).


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