Simple SI Unit Model for SWMM5 LID with 100 mm Rainfall - Part 2

This blog is a companion to the blog post https://swmm5.org/2017/04/17/swmm5-simple-100-mm-rainfall-model-for-lid-modeling-part-1/ in which a 1 Hectare model with 100 mm of rainfall had a simple Bio-Retention Cell with no LID outflows.  In part 2 of this blog series we will add a drain coefficient of 10 mm/hr (Figure 1).  The internal pervious area is 0.375 hectares, the nonLID area is 0.75 hectares and the two impervious area are 0.1875 hectares each. The example uses 100 mm of rainfall or precipitation to make the comparisons easier.  The LID Drainage outflow of 27.93 mm (Figure 2) is 6.98 mm over the whole 1 hectare Subcatchment (Figure 3).

The BMP removal is still 100 percent of the SF1 pollutant generation


Figure 1 A 10 mm/hr Drain Coefficient to the LID

Figure 2  The LID now has Drain outflow of 27.84 mm

Figure 3 The LID Drainage outflow of 27.93 mm (Figure 2) is 6.98 mm over the whole 1 hectare Subcatchment




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