diff --git a/examples/sim_poly_fi2p_comp_ad.cpp b/examples/sim_poly_fi2p_comp_ad.cpp
index ae5b91ef0..cef9191c8 100644
--- a/examples/sim_poly_fi2p_comp_ad.cpp
+++ b/examples/sim_poly_fi2p_comp_ad.cpp
@@ -37,7 +37,7 @@
 #include <opm/core/utility/parameters/ParameterGroup.hpp>
 
 #include <opm/material/fluidmatrixinteractions/EclMaterialLawManager.hpp>
-#include <opm/output/eclipse/EclipseWriter.hpp>
+#include <opm/output/eclipse/EclipseIO.hpp>
 #include <opm/core/props/BlackoilPropertiesBasic.hpp>
 #include <opm/core/props/BlackoilPropertiesFromDeck.hpp>
 #include <opm/core/props/rock/RockCompressibility.hpp>
@@ -239,11 +239,11 @@ try
     std::cout << "\n\n================    Starting main simulation loop     ===============\n"
               << std::flush;
 
-    std::unique_ptr<Opm::EclipseWriter>
-        eclipseWriter(new Opm::EclipseWriter(*eclipseState,
-                                             UgGridHelpers
-                                             ::createEclipseGrid( cGrid ,
-                                                                  eclipseState->getInputGrid())));
+    std::unique_ptr<Opm::EclipseIO>
+        eclipseWriter(new Opm::EclipseIO(*eclipseState,
+                                         UgGridHelpers
+                                         ::createEclipseGrid( cGrid ,
+                                                              eclipseState->getInputGrid())));
     Opm::BlackoilOutputWriter
         outputWriter(cGrid, param, *eclipseState, std::move(eclipseWriter), pu,
                      new_props->permeability() );
diff --git a/opm/autodiff/FlowMain.hpp b/opm/autodiff/FlowMain.hpp
index 47c7240af..f1d6b1fdf 100644
--- a/opm/autodiff/FlowMain.hpp
+++ b/opm/autodiff/FlowMain.hpp
@@ -234,7 +234,7 @@ namespace Opm
         // distributeData()
         boost::any parallel_information_;
         // setupOutputWriter()
-        std::unique_ptr<EclipseWriter> eclipse_writer_;
+        std::unique_ptr<EclipseIO> eclipse_writer_;
         std::unique_ptr<OutputWriter> output_writer_;
         // setupLinearSolver
         std::unique_ptr<NewtonIterationBlackoilInterface> fis_solver_;
@@ -762,7 +762,7 @@ namespace Opm
             if( output && output_ecl && output_cout_)
             {
                 const EclipseGrid& inputGrid = eclipse_state_->getInputGrid();
-                eclipse_writer_.reset(new EclipseWriter(*eclipse_state_, UgGridHelpers::createEclipseGrid( grid , inputGrid )));
+                eclipse_writer_.reset(new EclipseIO(*eclipse_state_, UgGridHelpers::createEclipseGrid( grid , inputGrid )));
                 eclipse_writer_->writeInitial(geoprops_->simProps(grid),
                                               geoprops_->nonCartesianConnections());
             }
diff --git a/opm/autodiff/FlowMainEbos.hpp b/opm/autodiff/FlowMainEbos.hpp
index f3c353817..975d9ffe9 100644
--- a/opm/autodiff/FlowMainEbos.hpp
+++ b/opm/autodiff/FlowMainEbos.hpp
@@ -545,8 +545,8 @@ namespace Opm
             if( output && output_ecl && output_cout_)
             {
                 const EclipseGrid& inputGrid = eclState().getInputGrid();
-                eclipse_writer_.reset(new EclipseWriter(eclState(), UgGridHelpers::createEclipseGrid( grid , inputGrid )));
-                eclipse_writer_->writeInitial(geoprops_->simProps(grid),
+                eclIO_.reset(new EclipseIO(eclState(), UgGridHelpers::createEclipseGrid( grid , inputGrid )));
+                eclIO_->writeInitial(geoprops_->simProps(grid),
                                               geoprops_->nonCartesianConnections());
             }
         }
@@ -562,7 +562,7 @@ namespace Opm
             output_writer_.reset(new OutputWriter(grid(),
                                                   param_,
                                                   eclState(),
-                                                  std::move(eclipse_writer_),
+                                                  std::move(eclIO_),
                                                   Opm::phaseUsageFromDeck(deck()),
                                                   fluidprops_->permeability()));
         }
@@ -725,7 +725,7 @@ namespace Opm
         std::unique_ptr<BlackoilPropsAdFromDeck> fluidprops_;
         std::unique_ptr<DerivedGeology> geoprops_;
         std::unique_ptr<ReservoirState> state_;
-        std::unique_ptr<EclipseWriter> eclipse_writer_;
+        std::unique_ptr<EclipseIO> eclIO_;
         std::unique_ptr<OutputWriter> output_writer_;
         boost::any parallel_information_;
         std::unique_ptr<NewtonIterationBlackoilInterface> fis_solver_;
diff --git a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.cpp b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.cpp
index 051ae9c91..32977925b 100644
--- a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.cpp
+++ b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.cpp
@@ -317,18 +317,18 @@ namespace Opm
         }
 
         // ECL output
-        if ( eclWriter_ )
+        if ( eclIO_ )
         {
             const auto& initConfig = eclipseState_.getInitConfig();
             if (initConfig.restartRequested() && ((initConfig.getRestartStep()) == (timer.currentStepNum()))) {
                 std::cout << "Skipping restart write in start of step " << timer.currentStepNum() << std::endl;
             } else {
                 // ... insert "extra" data (KR, VISC, ...)
-                eclWriter_->writeTimeStep(timer.reportStepNum(),
-                                          substep,
-                                          timer.simulationTimeElapsed(),
-                                          simProps,
-                                          wellState.report(phaseUsage_));
+                eclIO_->writeTimeStep(timer.reportStepNum(),
+                                      substep,
+                                      timer.simulationTimeElapsed(),
+                                      simProps,
+                                      wellState.report(phaseUsage_));
             }
         }
 
diff --git a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
index aed311313..191f68dc4 100644
--- a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
+++ b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
@@ -26,14 +26,13 @@
 #include <opm/core/utility/DataMap.hpp>
 #include <opm/common/ErrorMacros.hpp>
 #include <opm/common/OpmLog/OpmLog.hpp>
-#include <opm/output/eclipse/EclipseReader.hpp>
 #include <opm/core/utility/miscUtilities.hpp>
 #include <opm/core/utility/parameters/ParameterGroup.hpp>
 #include <opm/core/wells/DynamicListEconLimited.hpp>
 
 #include <opm/output/data/Cells.hpp>
 #include <opm/output/data/Solution.hpp>
-#include <opm/output/eclipse/EclipseWriter.hpp>
+#include <opm/output/eclipse/EclipseIO.hpp>
 
 #include <opm/autodiff/GridHelpers.hpp>
 #include <opm/autodiff/ParallelDebugOutput.hpp>
@@ -208,7 +207,7 @@ namespace Opm
         BlackoilOutputWriter(const Grid& grid,
                              const parameter::ParameterGroup& param,
                              const Opm::EclipseState& eclipseState,
-                             std::unique_ptr<EclipseWriter>&& eclWriter,
+                             std::unique_ptr<EclipseIO>&& eclIO,
                              const Opm::PhaseUsage &phaseUsage,
                              const double* permeability );
 
@@ -305,7 +304,7 @@ namespace Opm
         Opm::PhaseUsage phaseUsage_;
         std::unique_ptr< BlackoilSubWriter > vtkWriter_;
         std::unique_ptr< BlackoilSubWriter > matlabWriter_;
-        std::unique_ptr< EclipseWriter > eclWriter_;
+        std::unique_ptr< EclipseIO > eclIO_;
         const EclipseState& eclipseState_;
 
         std::unique_ptr< ThreadHandle > asyncOutput_;
@@ -323,7 +322,7 @@ namespace Opm
     BlackoilOutputWriter(const Grid& grid,
                          const parameter::ParameterGroup& param,
                          const Opm::EclipseState& eclipseState,
-                         std::unique_ptr<EclipseWriter>&& eclWriter,
+                         std::unique_ptr<EclipseIO>&& eclIO,
                          const Opm::PhaseUsage &phaseUsage,
                          const double* permeability )
       : output_( param.getDefault("output", true) ),
@@ -360,7 +359,7 @@ namespace Opm
                         .reset(new BlackoilMatlabWriter< Grid >( grid, outputDir_ ));
                 }
 
-                eclWriter_ = std::move(eclWriter);
+                eclIO_ = std::move(eclIO);
 
                 // Ensure that output dir exists
                 boost::filesystem::path fpath(outputDir_);
@@ -406,6 +405,13 @@ namespace Opm
                          SimulationDataContainer& simulatorstate,
                          WellStateFullyImplicitBlackoil& wellstate)
     {
+        std::map<std::string, UnitSystem::measure> solution_keys {{"PRESSURE" , UnitSystem::measure::pressure},
+                                                                  {"SWAT" , UnitSystem::measure::identity},
+                                                                  {"SGAS" , UnitSystem::measure::identity},
+                                                                  {"TEMP" , UnitSystem::measure::temperature},
+                                                                  {"RS" , UnitSystem::measure::gas_oil_ratio},
+                                                                  {"RV" , UnitSystem::measure::oil_gas_ratio}};
+
         // gives a dummy dynamic_list_econ_limited
         DynamicListEconLimited dummy_list_econ_limited;
         WellsManager wellsmanager(eclipseState_,
@@ -428,12 +434,10 @@ namespace Opm
 
         const Wells* wells = wellsmanager.c_wells();
         wellstate.resize(wells, simulatorstate); //Resize for restart step
-        auto restarted = Opm::init_from_restart_file(
-                                eclipseState_,
-                                Opm::UgGridHelpers::numCells(grid) );
+        auto state = eclIO_->loadRestart(solution_keys);
 
-        solutionToSim( restarted.first, phaseusage, simulatorstate );
-        wellsToState( restarted.second, phaseusage, wellstate );
+        solutionToSim( state.first, phaseusage, simulatorstate );
+        wellsToState( state.second, phaseusage, wellstate );
     }
 
 
diff --git a/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.cpp b/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.cpp
index 85480608c..6c8405ec3 100644
--- a/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.cpp
+++ b/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.cpp
@@ -156,7 +156,7 @@ namespace Opm
                         bool substep)
     {
         // ECL output
-        if ( eclWriter_ )
+        if ( eclIO_ )
         {
             const auto& initConfig = eclipseState_.getInitConfig();
             if (initConfig.restartRequested() && ((initConfig.getRestartStep()) == (timer.currentStepNum()))) {
@@ -164,11 +164,11 @@ namespace Opm
             } else {
                 data::Solution combined_sol = simToSolution(state, phaseUsage_); // Get "normal" data (SWAT, PRESSURE, ...)
                 combined_sol.insert(sol.begin(), sol.end());           // ... insert "extra" data (KR, VISC, ...)
-                eclWriter_->writeTimeStep(timer.reportStepNum(),
-                                          substep,
-                                          timer.simulationTimeElapsed(),
-                                          combined_sol,
-                                          wellState.report(phaseUsage_));
+                eclIO_->writeTimeStep(timer.reportStepNum(),
+                                      substep,
+                                      timer.simulationTimeElapsed(),
+                                      combined_sol,
+                                      wellState.report(phaseUsage_));
             }
         }
 
diff --git a/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.hpp b/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.hpp
index b2c1b4bf0..ee6e8e28a 100644
--- a/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.hpp
+++ b/opm/autodiff/SimulatorFullyImplicitBlackoilOutputEbos.hpp
@@ -25,12 +25,11 @@
 #include <opm/core/utility/DataMap.hpp>
 #include <opm/common/ErrorMacros.hpp>
 #include <opm/common/OpmLog/OpmLog.hpp>
-#include <opm/output/eclipse/EclipseReader.hpp>
 #include <opm/core/utility/miscUtilities.hpp>
 #include <opm/core/utility/parameters/ParameterGroup.hpp>
 #include <opm/core/wells/DynamicListEconLimited.hpp>
 
-#include <opm/output/eclipse/EclipseWriter.hpp>
+#include <opm/output/eclipse/EclipseIO.hpp>
 
 #include <opm/autodiff/Compat.hpp>
 #include <opm/autodiff/GridHelpers.hpp>
@@ -70,7 +69,7 @@ namespace Opm
         BlackoilOutputWriterEbos(const Grid& grid,
                                  const parameter::ParameterGroup& param,
                                  const EclipseState& eclipseState,
-                                 std::unique_ptr<EclipseWriter>&& eclWriter,
+                                 std::unique_ptr<EclipseIO>&& eclIO,
                                  const Opm::PhaseUsage &phaseUsage,
                                  const double* permeability );
 
@@ -162,7 +161,7 @@ namespace Opm
 
         std::ofstream backupfile_;
         Opm::PhaseUsage phaseUsage_;
-        std::unique_ptr<EclipseWriter> eclWriter_;
+        std::unique_ptr<EclipseIO> eclIO_;
         const EclipseState& eclipseState_;
 
         std::unique_ptr< ThreadHandle > asyncOutput_;
@@ -180,7 +179,7 @@ namespace Opm
     BlackoilOutputWriterEbos(const Grid& grid,
                              const parameter::ParameterGroup& param,
                              const Opm::EclipseState& eclipseState,
-                             std::unique_ptr<EclipseWriter>&& eclWriter,
+                             std::unique_ptr<EclipseIO>&& eclIO,
                              const Opm::PhaseUsage &phaseUsage,
                              const double* permeability )
       : output_( param.getDefault("output", true) ),
@@ -194,7 +193,7 @@ namespace Opm
     {
         // For output.
         if (output_ && parallelOutput_->isIORank() ) {
-            eclWriter_ = std::move(eclWriter);
+            eclIO_ = std::move(eclIO);
 
             // Ensure that output dir exists
             boost::filesystem::path fpath(outputDir_);
@@ -239,6 +238,13 @@ namespace Opm
                          SimulationDataContainer& simulatorstate,
                          WellStateFullyImplicitBlackoilDense& wellstate)
     {
+        std::map<std::string, UnitSystem::measure> solution_keys {{"PRESSURE" , UnitSystem::measure::pressure},
+                                                                  {"SWAT" , UnitSystem::measure::identity},
+                                                                  {"SGAS" , UnitSystem::measure::identity},
+                                                                  {"TEMP" , UnitSystem::measure::temperature},
+                                                                  {"RS" , UnitSystem::measure::gas_oil_ratio},
+                                                                  {"RV" , UnitSystem::measure::oil_gas_ratio}};
+
         // gives a dummy dynamic_list_econ_limited
         DynamicListEconLimited dummy_list_econ_limited;
         WellsManager wellsmanager(eclipseState_,
@@ -261,12 +267,9 @@ namespace Opm
 
         const Wells* wells = wellsmanager.c_wells();
         wellstate.resize(wells, simulatorstate, phaseusage ); //Resize for restart step
-        auto restarted = Opm::init_from_restart_file(
-                                eclipseState_,
-                                Opm::UgGridHelpers::numCells(grid) );
-
-        solutionToSim( restarted.first, phaseusage, simulatorstate );
-        wellsToState( restarted.second, phaseusage, wellstate );
+        auto state = eclIO_->loadRestart(solution_keys);
+        solutionToSim( state.first, phaseusage, simulatorstate );
+        wellsToState( state.second, phaseusage, wellstate );
     }
 
 
diff --git a/opm/polymer/fullyimplicit/SimulatorFullyImplicitCompressiblePolymer.hpp b/opm/polymer/fullyimplicit/SimulatorFullyImplicitCompressiblePolymer.hpp
index 1c22d5ed2..580fa4a77 100644
--- a/opm/polymer/fullyimplicit/SimulatorFullyImplicitCompressiblePolymer.hpp
+++ b/opm/polymer/fullyimplicit/SimulatorFullyImplicitCompressiblePolymer.hpp
@@ -38,7 +38,7 @@
 #include <opm/core/simulator/SimulatorReport.hpp>
 #include <opm/core/simulator/SimulatorTimer.hpp>
 #include <opm/core/utility/StopWatch.hpp>
-#include <opm/output/eclipse/EclipseWriter.hpp>
+#include <opm/output/eclipse/EclipseIO.hpp>
 #include <opm/core/utility/miscUtilities.hpp>
 #include <opm/core/utility/miscUtilitiesBlackoil.hpp>