I also noticed that under where it says L402-12 it says 24.91 AC. Could that mean that the area inside that border is 24.91 acres? If so, then once you take off the top area where Echo Lake is (assuming it is still not included), and possibly add in the top part of the front half of CM parking lot, then perhaps we can get an idea of the SWL area. And maybe it's just me but the area doesn't seem to be as big as I thought it would be if that's the case.No, those lines show the borders of drainage basins which are different area of storm water control.