Application of the VWBA Withdrawal Method to Incorporate Precipitation Variability for Agricultural Activities that Reduce Water Applied to Crops • Bluerisk

This guidance document prepared by Bluerisk and Kilimo provides an example application of the Volumetric Water Benefit Accounting (VWBA) withdrawal method to explicitly account for precipitation in Volumetric Water Benefit (VWB) estimates to isolate the additionality of activities and reduce the risk of overclaiming VWBs in the context of agricultural activities.

This application of the withdrawal method reduces variability by considering average historical precipitation trends to improve consistency in VWB estimates year to year.

The objectives of this withdrawal method application are to:

• Explicitly account for precipitation in VWB estimates to isolate the additionality of the activity and reduce the risk of overclaiming VWBs 
• Reduce variability by improving consistency in VWB estimates year to year

This guidance document includes:

• Information on the example application of the withdrawal method
• Best practice guidance for data collection and use
• Example case studies for applying the method
• An example data collection survey for farmers.