This forum is shutting down! Please post new discussions at

Hydrological definition of Water Yield?

Dear NatCap team,

First, congratulations for the great job you are doing!

Second, is there any place in the manual where I can find the definition of "water yield'?

Can I roughly understand it as the difference between Precipitation and Evapotranspiration?

Is the Water yield = Runoff + subsurface flow?

Thanks a lot!!
Best wishes,


  • PerrinePerrine Moderator, NatCap Staff
    Hi Elena, 

    The answer to both your question is yes!

    Water yield is the amount of water "produced" by the watershed, i.e. the difference between precipitation and evapotranspiration.
    Water yield does include overland flow and subsurface flow (and typically, in a natural watershed, most of the runoff reaches the stream via subsurface flow).

    This also assumes that there's minimal loss to deep groundwater (i.e. water that is not evapotranspired but is not seen in the stream at the scale of the watershed -- only further downstream).


  • elenaelena Member
    Thanks a lot Perrine!!

  • can i have a sample thesis for water yield model?
  • swolnyswolny Member, NatCap Staff
    Hi Nuwan_Wettansinghe -

    I'm not sure what you're looking for when you ask for a "thesis" for the water yield model. Our User Guide contains information on the background, equations, data etc that go into the model. And if you search our library for "water yield", you'll find papers and articles on places that the water yield model has been used.

    ~ Stacie
Sign In or Register to comment.