diff --git a/DaSaSo.ViewModel/BuildingsiteEditViewModel.cs b/DaSaSo.ViewModel/BuildingsiteEditViewModel.cs
index f4c85ef..27c5354 100644
--- a/DaSaSo.ViewModel/BuildingsiteEditViewModel.cs
+++ b/DaSaSo.ViewModel/BuildingsiteEditViewModel.cs
@@ -75,7 +75,7 @@ namespace DaSaSo.ViewModel
         private void SaveBuildingsite()
         {
             _buildingsiteService.Update(Model.Id, Model);
-            _renavigator.Renavigate(new BuildingsiteListViewModel(_buildingsiteService, _actualProject, _renavigator, null));
+            _renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/ClientEditViewModel.cs b/DaSaSo.ViewModel/ClientEditViewModel.cs
index f331e11..fc88421 100644
--- a/DaSaSo.ViewModel/ClientEditViewModel.cs
+++ b/DaSaSo.ViewModel/ClientEditViewModel.cs
@@ -35,7 +35,7 @@ namespace DaSaSo.ViewModel
         private void SaveClient()
         {
             _dataService.Update(Model.Id, Model);
-            renavigator.Renavigate(new ClientListViewModel(_dataService,_actualProject,renavigator));
+            renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/ClientListViewModel.cs b/DaSaSo.ViewModel/ClientListViewModel.cs
index 48c01f3..00bb5cc 100644
--- a/DaSaSo.ViewModel/ClientListViewModel.cs
+++ b/DaSaSo.ViewModel/ClientListViewModel.cs
@@ -59,18 +59,22 @@ namespace DaSaSo.ViewModel
 
         public bool CanSelectClient => _selectedClient != null;
 
-        public ClientListViewModel(IDataService<Client> dataService, IActualProject actualProject, IRenavigator renavigator)
+        public ClientListViewModel(IDataService<Client> dataService, IActualProject actualProject, IRenavigator editRenavigator)
         {
             Clients = new ObservableCollection<Client>();
             _dataService = dataService;
             this.renavigator = renavigator;
             LoadClient();
             SelectCommand = new SelectClientCommand(actualProject, this); //= new RelayCommand(SelectClient, () => SelectedClient != null);
-            EditCommand = new EditClientCommand(_dataService,actualProject,renavigator,this);
-            AddNewClientCommand = new AddClientCommand(_dataService, actualProject, renavigator, this);
+            EditCommand = new EditClientCommand(_dataService,actualProject, editRenavigator, this);
+            AddNewClientCommand = new AddClientCommand(_dataService, actualProject, editRenavigator, this);
 
         }
 
+        ~ClientListViewModel()
+        {
+
+        }
 
         public async void LoadClient()
         {
diff --git a/DaSaSo.ViewModel/Commands/AddBuildingsiteCommand.cs b/DaSaSo.ViewModel/Commands/AddBuildingsiteCommand.cs
index 6ed4115..a1408bc 100644
--- a/DaSaSo.ViewModel/Commands/AddBuildingsiteCommand.cs
+++ b/DaSaSo.ViewModel/Commands/AddBuildingsiteCommand.cs
@@ -28,7 +28,7 @@ namespace DaSaSo.ViewModel.Commands
         {
             Buildingsite buildingsite = await _buildingsiteService.CreateBuildingsite(_actualProject.AktuellProjekt);
             _actualProject.SetBuildingSite(buildingsite);
-            _renavigator.Renavigate(new BuildingsiteEditViewModel(_dataservice, _actualProject, _renavigator));
+            _renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/Commands/AddClientCommand.cs b/DaSaSo.ViewModel/Commands/AddClientCommand.cs
index 53e83b2..b1cfab5 100644
--- a/DaSaSo.ViewModel/Commands/AddClientCommand.cs
+++ b/DaSaSo.ViewModel/Commands/AddClientCommand.cs
@@ -30,7 +30,7 @@ namespace DaSaSo.ViewModel.Commands
             Client newClient = await dataservice.Create(new Client());
             actualProject.SetClient(newClient,false);
             //actualProject.SetClient(clientListViewModel.SelectedClient);
-            renavigator.Renavigate(new ClientEditViewModel(dataservice, actualProject, renavigator));
+            renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/Commands/AddProjectCommand.cs b/DaSaSo.ViewModel/Commands/AddProjectCommand.cs
index c61d96e..b5862d0 100644
--- a/DaSaSo.ViewModel/Commands/AddProjectCommand.cs
+++ b/DaSaSo.ViewModel/Commands/AddProjectCommand.cs
@@ -31,7 +31,7 @@ namespace DaSaSo.ViewModel.Commands
         {
             Project pro = await _projectService.CreateProject(_actualProject.AktuellClient);
             _actualProject.SetProject(pro);
-            _renavigator.Renavigate(new ProjectEditViewModel(_genericDataService, _actualProject, _renavigator, _projectService));
+            _renavigator.Renavigate();
             
         }
     }
diff --git a/DaSaSo.ViewModel/Commands/EditBuildingsiteCommand.cs b/DaSaSo.ViewModel/Commands/EditBuildingsiteCommand.cs
index 0e1464f..610e0a3 100644
--- a/DaSaSo.ViewModel/Commands/EditBuildingsiteCommand.cs
+++ b/DaSaSo.ViewModel/Commands/EditBuildingsiteCommand.cs
@@ -42,7 +42,7 @@ namespace DaSaSo.ViewModel.Commands
         public override async Task ExecuteAsync(object? parameter)
         {
             actualProject.SetBuildingSite(_buildingsiteListViewModel.SelectedBuildingsite);
-            renavigator.Renavigate(new BuildingsiteEditViewModel(buildingSiteDataService, actualProject, renavigator));
+            renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/Commands/EditClientCommand.cs b/DaSaSo.ViewModel/Commands/EditClientCommand.cs
index ccb770c..9f7e7e2 100644
--- a/DaSaSo.ViewModel/Commands/EditClientCommand.cs
+++ b/DaSaSo.ViewModel/Commands/EditClientCommand.cs
@@ -45,7 +45,7 @@ namespace DaSaSo.ViewModel.Commands
         public override async Task ExecuteAsync(object? parameter)
         {
             actualProject.SetClient(_clientListViewModel.SelectedClient);
-            renavigator.Renavigate(new ClientEditViewModel(dataservice,actualProject,renavigator));
+            renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/Commands/EditProjectCommand.cs b/DaSaSo.ViewModel/Commands/EditProjectCommand.cs
index a7e2c78..2d7a143 100644
--- a/DaSaSo.ViewModel/Commands/EditProjectCommand.cs
+++ b/DaSaSo.ViewModel/Commands/EditProjectCommand.cs
@@ -42,7 +42,7 @@ namespace DaSaSo.ViewModel.Commands
         public override async Task ExecuteAsync(object? parameter)
         {
             _actualProject.SetProject(_projectListViewModel.SelectedProject);
-            _renavigator.Renavigate(new ProjectEditViewModel(_dataService, _actualProject, _renavigator,_projectService));
+            _renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/Commands/SaveSewerCommand.cs b/DaSaSo.ViewModel/Commands/SaveSewerCommand.cs
index 20a2676..adfea0a 100644
--- a/DaSaSo.ViewModel/Commands/SaveSewerCommand.cs
+++ b/DaSaSo.ViewModel/Commands/SaveSewerCommand.cs
@@ -42,7 +42,7 @@ namespace DaSaSo.ViewModel.Commands
         public override async Task ExecuteAsync(object? parameter)
         {
             _navigator.CurrentViewModel = null;
-            _renavigator.Renavigate(new SewerObjectListViewModel(_dataService, _actualProject, _sewerObjectService));
+            _renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/Interface/IRenavigator.cs b/DaSaSo.ViewModel/Interface/IRenavigator.cs
index 3066d97..b744d9a 100644
--- a/DaSaSo.ViewModel/Interface/IRenavigator.cs
+++ b/DaSaSo.ViewModel/Interface/IRenavigator.cs
@@ -8,6 +8,6 @@ namespace DaSaSo.ViewModel.Interface
 {
     public interface IRenavigator
     {
-        void Renavigate(BaseViewModel target);
+        void Renavigate();
     }
 }
diff --git a/DaSaSo.ViewModel/ProjectEditViewModel.cs b/DaSaSo.ViewModel/ProjectEditViewModel.cs
index 4598312..bb6fe7e 100644
--- a/DaSaSo.ViewModel/ProjectEditViewModel.cs
+++ b/DaSaSo.ViewModel/ProjectEditViewModel.cs
@@ -62,7 +62,7 @@ namespace DaSaSo.ViewModel
         private void SaveProject()
         {
             _dataservice.Update(_model.Id, _model);
-            _renavigator.Renavigate(new ProjectListViewModel(_dataservice, _actualProject, _renavigator, _projectService));
+            _renavigator.Renavigate();
         }
     }
 }
diff --git a/DaSaSo.ViewModel/SewerMainListViewModel.cs b/DaSaSo.ViewModel/SewerMainListViewModel.cs
index 9c9c825..8f5581b 100644
--- a/DaSaSo.ViewModel/SewerMainListViewModel.cs
+++ b/DaSaSo.ViewModel/SewerMainListViewModel.cs
@@ -81,5 +81,11 @@ namespace DaSaSo.ViewModel
             _actualProject.SetSewerObject(sewer,false);
             IsLoading = false;
         }
+
+        public override void Dispose()
+        {
+            _navigator.StateChanged -= () => OnPropertyChanged(nameof(CurrentSewerViewModel));
+            base.Dispose();
+        }
     }
 }
diff --git a/DaSaSo.ViewModel/State/Navigation/ViewModelDelegateRenavigator.cs b/DaSaSo.ViewModel/State/Navigation/ViewModelDelegateRenavigator.cs
index d7714d7..d174446 100644
--- a/DaSaSo.ViewModel/State/Navigation/ViewModelDelegateRenavigator.cs
+++ b/DaSaSo.ViewModel/State/Navigation/ViewModelDelegateRenavigator.cs
@@ -7,19 +7,20 @@ using System.Threading.Tasks;
 
 namespace DaSaSo.ViewModel.State.Navigation
 {
-    public class ViewModelDelegateRenavigator : IRenavigator
+    public class ViewModelDelegateRenavigator<TViewModel> : IRenavigator where TViewModel: BaseViewModel
     {
         private readonly IMainWindowNavigator _navigator;
-        
+        private readonly CreateViewModel<TViewModel> _createViewModel;
 
-        public ViewModelDelegateRenavigator(IMainWindowNavigator navigator)
+        public ViewModelDelegateRenavigator(IMainWindowNavigator navigator, CreateViewModel<TViewModel> createViewModel)
         {
             _navigator = navigator;
+            _createViewModel = createViewModel;
         }
 
-        public void Renavigate(BaseViewModel target)
+        public void Renavigate()
         {
-            _navigator.CurrentViewModel = target;
+            _navigator.CurrentViewModel = _createViewModel();
         }
     }
 }
diff --git a/DaSaSo.Wpf/HostBuilders/AddServicesHostBuilderExtensions.cs b/DaSaSo.Wpf/HostBuilders/AddServicesHostBuilderExtensions.cs
index 32790e4..950d7e8 100644
--- a/DaSaSo.Wpf/HostBuilders/AddServicesHostBuilderExtensions.cs
+++ b/DaSaSo.Wpf/HostBuilders/AddServicesHostBuilderExtensions.cs
@@ -23,7 +23,7 @@ namespace DaSaSo.Wpf.HostBuilders
             {
                 services.AddSingleton<IDataService<Client>, ClientDataService>();
                 services.AddSingleton<IDataService<Project>, ProjectDataService>();
-                services.AddSingleton<IDataService<Buildingsite>, BuildingsiteDataService>();
+                services.AddTransient<IDataService<Buildingsite>, BuildingsiteDataService>();
                 services.AddSingleton<IDataService<SewerObject>, SewerObjectDataService>();
                 services.AddSingleton<IDataService<SewerPoint>, SewerpointDataService>();
                 services.AddSingleton<IProjectService, ProjectService>();
diff --git a/DaSaSo.Wpf/HostBuilders/AddViewModelsHostBuilderExtensions.cs b/DaSaSo.Wpf/HostBuilders/AddViewModelsHostBuilderExtensions.cs
index 8952aeb..43742d0 100644
--- a/DaSaSo.Wpf/HostBuilders/AddViewModelsHostBuilderExtensions.cs
+++ b/DaSaSo.Wpf/HostBuilders/AddViewModelsHostBuilderExtensions.cs
@@ -28,20 +28,38 @@ namespace DaSaSo.Wpf.HostBuilders
                 services.AddTransient<MainWindowViewModel>();
                 services.AddSingleton<ClientListViewModel>();
 
-                services.AddTransient<SewerMainListViewModel>();
+                services.AddSingleton<ViewModelDelegateRenavigator<ClientListViewModel>>();
+                services.AddSingleton<ViewModelDelegateRenavigator<ClientEditViewModel>>();
+
+                services.AddSingleton<ViewModelDelegateRenavigator<ProjectListViewModel>>();
+                services.AddSingleton<ViewModelDelegateRenavigator<ProjectEditViewModel>>();
+
+                services.AddSingleton<ViewModelDelegateRenavigator<BuildingsiteListViewModel>>();
+                services.AddSingleton<ViewModelDelegateRenavigator<BuildingsiteEditViewModel>>();
+
+                services.AddSingleton<ViewModelDelegateRenavigator<SewerObjectListViewModel>>();
 
                 services.AddSingleton<CreateViewModel<HomeViewModel>>(services =>
                 {
                     return () => new HomeViewModel();
                 });
-                services.AddSingleton<CreateViewModel<ClientEditViewModel>>(services =>
+                services.AddTransient<CreateViewModel<ClientEditViewModel>>(services =>
                 {
                     return () => new ClientEditViewModel(
                          services.GetRequiredService<IDataService<Client>>(),
                          services.GetRequiredService<IActualProject>(),
-                         new ViewModelDelegateRenavigator(
-                             services.GetRequiredService<IMainWindowNavigator>()
-                         ));
+                         services.GetRequiredService<ViewModelDelegateRenavigator<ClientListViewModel>>()
+                         );
+                         
+                });
+                services.AddTransient<CreateViewModel<ProjectEditViewModel>>(services =>
+                {
+                    return () => new ProjectEditViewModel(
+                        services.GetRequiredService<IDataService<Project>>(),
+                        services.GetRequiredService<IActualProject>(),
+                        services.GetRequiredService<ViewModelDelegateRenavigator<ProjectListViewModel>>(),
+                        services.GetRequiredService<IProjectService>()
+                        );
                 });
                 services.AddSingleton<CreateViewModel<HomeViewModel>>(services =>
                 {
@@ -65,14 +83,14 @@ namespace DaSaSo.Wpf.HostBuilders
                         );
                 });
 
-                services.AddSingleton<CreateViewModel<ClientListViewModel>>(services =>
+                services.AddTransient<CreateViewModel<ClientListViewModel>>(services =>
                 {
                     return () => new ClientListViewModel(
                         services.GetRequiredService<IDataService<Client>>(),
                         services.GetRequiredService<IActualProject>(),
-                        new ViewModelDelegateRenavigator(
-                            services.GetRequiredService<IMainWindowNavigator>()
-                        ));
+                        services.GetRequiredService<ViewModelDelegateRenavigator<ClientEditViewModel>>()
+                        );
+
                 });
                 services.AddSingleton<CreateViewModel<SewerMainListViewModel>>(services =>
                 {
@@ -81,9 +99,7 @@ namespace DaSaSo.Wpf.HostBuilders
                         services.GetRequiredService<ISewerMainNavigator>(),
                         services.GetRequiredService<IActualProject>(),
                         services.GetRequiredService<IViewModelSewerMainFactory>(),
-                        new ViewModelDelegateRenavigator(
-                            services.GetRequiredService<IMainWindowNavigator>()
-                            ),
+                       services.GetRequiredService<ViewModelDelegateRenavigator<SewerObjectListViewModel>>(),
                         services.GetRequiredService<ISewerObjectService>(),
                         services.GetRequiredService<ISewerpointService>()
                         );
@@ -93,24 +109,31 @@ namespace DaSaSo.Wpf.HostBuilders
                     return () => new ProjectListViewModel(
                         services.GetRequiredService<IDataService<Project>>(),
                         services.GetRequiredService<IActualProject>(),
-                        new ViewModelDelegateRenavigator(
-                            services.GetRequiredService<IMainWindowNavigator>()),
+                        services.GetRequiredService<ViewModelDelegateRenavigator<ProjectEditViewModel>>(),
                         services.GetRequiredService<IProjectService>()
 
                         );
                 });
 
-                services.AddSingleton<CreateViewModel<BuildingsiteListViewModel>>(services =>
+                services.AddTransient<CreateViewModel<BuildingsiteListViewModel>>(services =>
                 {
                     return () => new BuildingsiteListViewModel(
                         services.GetRequiredService<IDataService<Buildingsite>>(),
                         services.GetRequiredService<IActualProject>(),
-                        new ViewModelDelegateRenavigator(
-                            services.GetRequiredService<IMainWindowNavigator>()),
+                        services.GetRequiredService<ViewModelDelegateRenavigator<BuildingsiteEditViewModel>>(),
                         services.GetRequiredService<IBuildingsiteService>()
                         );
                 });
 
+                services.AddTransient<CreateViewModel<BuildingsiteEditViewModel>>(services =>
+                {
+                    return () => new BuildingsiteEditViewModel(
+                        services.GetRequiredService<IDataService<Buildingsite>>(),
+                        services.GetRequiredService<IActualProject>(),
+                        services.GetRequiredService<ViewModelDelegateRenavigator<BuildingsiteListViewModel>>()
+                        );
+                });
+
                 services.AddSingleton<CreateViewModel<SewerObjectListViewModel>>(services =>
                 {
                     return () => new SewerObjectListViewModel(