diff --git a/src/pab/cloisons.ts b/src/pab/cloisons.ts
index 993f8a62e242530d93ce9da430909caaaf749d67..8c3d8fe4822150f9815788047267d7d638d76323 100644
--- a/src/pab/cloisons.ts
+++ b/src/pab/cloisons.ts
@@ -92,6 +92,7 @@ export class Cloisons extends ParallelStructure {
         this.prms.BB.calculability = ParamCalculability.FREE;
         this.prms.PB.calculability = ParamCalculability.FREE;
         this.prms.DH.calculability = ParamCalculability.DICHO;
+        this.prms.Z1.calculability = ParamCalculability.FREE;
     }
 
     private updatePrms() {
diff --git a/src/pab/pab.ts b/src/pab/pab.ts
index 39c9b0467405363c2b889a90fc7bcdc4c578478a..cc384f647281369dd2518ff5dfb6208d61ef2623 100644
--- a/src/pab/pab.ts
+++ b/src/pab/pab.ts
@@ -158,7 +158,7 @@ export class Pab extends Nub {
         cl.Calc("Z1");
 
         // TODO: Add extraresults: discharge, apron elevation upstream the wall, apron elevation at half basin
-        cl.result.extraResults.YMOY = cl.prms.Z2.v - cl.result.extraResults.ZRB;
+        cl.result.extraResults.YMOY = cl.prms.Z2.v - cl.result.extraResults.ZRMB;
 
         // Update elevation and discharge for next basin
         return cl.prms.Z1.v;