diff --git a/ebos/equil/initstateequil.hh b/ebos/equil/initstateequil.hh
index cc2afa0ee..bfa60a124 100644
--- a/ebos/equil/initstateequil.hh
+++ b/ebos/equil/initstateequil.hh
@@ -1716,7 +1716,7 @@ public:
         calcPressSatRsRv(eqlmap, rec, materialLawManager, comm, grav);
 
         // modify the pressure and saturation for numerical aquifer cells
-        applyNumericalAquifers_(gridView, num_aquifers);
+        applyNumericalAquifers_(gridView, num_aquifers, eclipseState.runspec().co2Storage());
 
         // Modify oil pressure in no-oil regions so that the pressures of present phases can
         // be recovered from the oil pressure and capillary relations.
@@ -1815,7 +1815,8 @@ private:
     }
 
     void applyNumericalAquifers_(const GridView& gridView,
-                                 const NumericalAquifers& aquifer)
+                                 const NumericalAquifers& aquifer,
+                                 const bool co2store)
     {
         const auto num_aqu_cells = aquifer.allAquiferCells();
         if (num_aqu_cells.empty()) return;
@@ -1830,7 +1831,8 @@ private:
             const auto search = num_aqu_cells.find(cartIx);
             if (search != num_aqu_cells.end()) {
                 // numerical aquifer cells are filled with water initially
-                const auto watPos = FluidSystem::waterPhaseIdx;
+                // for co2store the oilphase is used for brine
+                const auto watPos = co2store? FluidSystem::oilPhaseIdx : FluidSystem::waterPhaseIdx;
                 if (FluidSystem::phaseIsActive(watPos)) {
                     this->sat_[watPos][elemIdx] = 1.;
                 } else {
@@ -1838,7 +1840,7 @@ private:
                 }
 
                 const auto oilPos = FluidSystem::oilPhaseIdx;
-                if (FluidSystem::phaseIsActive(oilPos)) {
+                if (!co2store && FluidSystem::phaseIsActive(oilPos)) {
                     this->sat_[oilPos][elemIdx] = 0.;
                 }