diff --git a/CHANGELOG.md b/CHANGELOG.md
index e1d6385c..0d734884 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 
 **Fixed:**
+- The bug in calculation of IS discussed in
+  [#252](https://github.com/EcoExtreML/STEMMUS_SCOPE/issues/252)
 
 
 <a name="1.6.0"></a>
diff --git a/run_model_on_snellius/exe/STEMMUS_SCOPE b/run_model_on_snellius/exe/STEMMUS_SCOPE
index 8b070199..e85f8560 100755
Binary files a/run_model_on_snellius/exe/STEMMUS_SCOPE and b/run_model_on_snellius/exe/STEMMUS_SCOPE differ
diff --git a/src/+init/soilHeteroSubroutine.m b/src/+init/soilHeteroSubroutine.m
index 042619ba..f78083f4 100644
--- a/src/+init/soilHeteroSubroutine.m
+++ b/src/+init/soilHeteroSubroutine.m
@@ -47,12 +47,12 @@
             j = i - 1;
         end
 
-        SoilVariables.IS(i) = indexOfSoilType;
+        SoilVariables.IS(j) = indexOfSoilType;
         if subRoutine == 4
             SoilVariables.IS(5:8) = 5;
         end
 
-        J = SoilVariables.IS(i);
+        J = SoilVariables.IS(j);
         [SoilVariables, VanGenuchten] = init.updateSoilVariables(SoilVariables, VanGenuchten, SoilProperties, ModelSettings, j, J);
         SoilVariables.Imped(i) = ImpedF(J);