When you are using CatchmentSIM's automatic catchment breakup algorithm
, you can choose which order streams you want to map catchments for. So, if you set this to 3, CatchmentSIM will not generate catchments for the 1st and 2nd order streams but only for 3rd order or higher.
Also, if you find you are getting lots of small first order streams, you can use the Minimum Source Channel Length
option to reduce the number.
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