Index: /issm/trunk-jpl/src/c/analyses/HydrologyDCInefficientAnalysis.cpp
===================================================================
--- /issm/trunk-jpl/src/c/analyses/HydrologyDCInefficientAnalysis.cpp	(revision 21571)
+++ /issm/trunk-jpl/src/c/analyses/HydrologyDCInefficientAnalysis.cpp	(revision 21572)
@@ -528,16 +528,8 @@
 
 	storing=rho_freshwater*g*sediment_porosity*sediment_thickness*(water_compressibility+(sediment_compressibility/sediment_porosity));
-	//porosity for unconfined region
-	if (water_sheet<=0.9*sediment_thickness){
-		sediment_storing=sediment_porosity;
-	}
-	//continuity ramp
-	else if((water_sheet<sediment_thickness) && (water_sheet>0.9*sediment_thickness)){
-		sediment_storing=(sediment_thickness-water_sheet)*(sediment_porosity-storing)/(0.1*sediment_thickness)+storing;
-	}
-	//storing coefficient for confined
-	else{
-		sediment_storing=storing;
-	}
+	
+	//Heavyside approximation (1/(1+exp(-2kx))) with k=25 centering at thickness minus 1%
+	sediment_storing=(sediment_porosity*exp(-20.*(water_sheet-0.99*sediment_thickness))+storing)/(1+exp(-20.*(water_sheet-0.99*sediment_thickness)));
+
 	return sediment_storing;
 }/*}}}*/