Lease Fallow Tool


The Lease Fallow Tool (LFT) was developed to simplify and streamline the evaluation of historical consumptive use, depletions, and return flows from irrigation.  The LFT is required for evaluation of HB13-1248 lease-fallowing pilot projects using conservative ET measures, but can also be used with more accurate ET datasets.


Major Features

The new LFT Version 8 includes many added features and improvements including:  

  • Full DSS model ditch data for the West Slope in addition to Divisions 1 and 3 including aggregated ditches and DSS ditch weightings.
  • The new ASCE Std. ET dataset can be used at climate stations or corrected to field locations using a 2.5 mile grid covering Colorado. The DSS, H-I Model, and SCS-TR-21 ET datasets can also still be used.
  • Crops can now be selected individually or as part of DSS or H-I model crop distributions. The ASCE Std. crop coefficients include several developed from Colorado lysimeter data.  

Installation Notes

An install file is available to install the LFT along with the prerequisite Matlab R2014a MCR on Windows 64bit computers. This requires administrative privileges.

  • The recommended install location is C:\CDSS\LFT (not the installer default)
  • You do not need to use the installer if the MCR or a previous version of the LFT has been installed.  Instead, the zipped files can be downloaded and copied to C:\CDSS\LFT\application etc. as this does not require administrative privileges.

Quick Start Notes

The LFT is run from an LFT Excel Template spreadsheet initially located in the application folder (can save to new name and location). Click Enable Content to enable Macros.

  • In blue section, enter dataset and location information for a field using the pulldowns in the first open row. Click ADD ROW for additional fields.;
  • Click BUILD INPUT DATA PAGES to load data for all ON fields. Modify field acres, shares and other data on _data pages. If crop distribution is changed click UPDATE PET FOR CROP DIST.
  • In orange section, select any analysis options and click RUN LFT ANALYSIS. Results will be on _S and _R pages.
  • After working with LFT, close all other Excel files and click CLEAR EXCEL PROCESSES.


Name Description File Type Release Date
LFT Installation Installation file –Version 8.04 with 1950-2022 data Application 6/23/2023
LFT Files Files if MCR is already installed – Version 8.04 with 1950-2022 data Zip 6/23/2023
User's Manual User's Manual and software documentation PDF 1/26/2016