There are standard curves of soil tension versus moisture content for different soil types (E.g. sand, sandy loan, clay loam, clay, etc.). Also there are similar standard curves of soil conductivity versus moisture content for different soil types.
I am running SWMM5 and two parameters I need are slope of these curves. I was able to find a couple of papers that have these curves for three different soil types but not all. So I wanted to know if anybody here knows where I can find these cyrves for all soil types.
Published data is available for such curves. These are for specific soils. Have you tried W3 searches or contacted NRCS for these? You can also utilize one of several methodologies to estimate such curves based upon soil texture.
I am unclear as to why such is needed for SWMM5. I do not know where within SWMM5 that unsaturated hydraulic conductivity is utilized. That is what such curves provide.
If you are utilizing the Green-Ampt or Horton infiltration methods, suggested parameters for such are included in the context-sensitive help. These methods assume saturated plug flow.
You might look into UNSODA for unsaturated soil data (
In SWMM5 when you run the groundwater analysis, there are two parameters that are required for simulating aquifers. These are the slopes of 1)tension vs. soil moisture curve and 2) hydraulic conductivity vs soil moisture curve. I believe these were referred to in SWMM4 as HCO and PCO. SWMM4 manual has these curves for sand, silt loam and sandy loam types of soil.
Thaks for the link, tsgrue. I will look into this software.
