This forum is shutting down! Please post new discussions at

seasonal water yield - output interpretation

MattiasMattias Member
edited May 2017 in Freshwater Models
I run the seasonal water yield tool to quantify the amount of annual groundwater recharge for a given area.
My question is: how much water is annualy destined to reach the groundwaters?
I can found a lot of outputs, but I don't understand which of these rasters represent the real groundwater recharge capacity.
Maybe is "L_sum_available" raster?
Moreover, since wetlands can both reacharge and discharge water to groundwater bodies, how can I deal with this problem? Should I consider map values provided by wetlands?
thanks in advance
Post edited by Mattias on


  • swolnyswolny Member, NatCap Staff
    Hi Matt -

    The seasonal water yield tool is not designed to quantify groundwater recharge. It can quantify quickflow - how much water runs off of the landscape soon after a rain event. It also provides an index of which places on the landscape are contributing more or less to dry season baseflow. But it does not address groundwater recharge.

    "Local recharge" in the SWY model is related to baseflow, not groundwater recharge. Sorry if the terminology is confusing. 

    ~ Stacie

  • MattiasMattias Member
    so the "L_sum_available" raster provides the amount of water (except for evapotraspiration) which is available for the baseflow, and baseflow is the amount of water that reach the water this correct?

    I attributed CN=0.1 to wetlands, how the model deals with water bodies? should I consider map values provided by wetlands?

    Moreover, I would like to assess the capacity of my study area to buffer floodings from nearby river.
    Could S = 25.4 (1000/CN - 10) a suitable indicator? or I should process some other model outputs?

    many thanks
  • Hi Stacie,

    I have the same question: how the model deals with water bodies?
    Which value of CN you recommend for water body when working with a watershed where there is a big dam near the exudory?



  • swolnyswolny Member, NatCap Staff
    Hi Mariana (and sorry, Matt for dropping the thread so long ago!) -

    We give a very high value (99) for water bodies, since that water has already made it to the stream (or reservoir, etc), and it's not likely to infiltrate.

    ~ Stacie
  • Thanks Stacie!
    Happy to know that I'm using the right value.
Sign In or Register to comment.