diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d6da3451a..2d9d1877a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -34,7 +34,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
diff --git a/build.gradle b/build.gradle
index 80d4bc1ff..b4785f541 100644
--- a/build.gradle
+++ b/build.gradle
@@ -16,7 +16,7 @@ plugins {
 
 ext {
   //version (changing these should be considered thoroughly!)
-  javaVersion = JavaVersion.VERSION_17
+  javaVersion = JavaVersion.VERSION_21
   groovyVersion = "4.0"
   groovyBinaryVersion = "4.0.28"
 
diff --git a/docs/readthedocs/gettingstarted.md b/docs/readthedocs/gettingstarted.md
index 2dea1825a..3f4b662ac 100644
--- a/docs/readthedocs/gettingstarted.md
+++ b/docs/readthedocs/gettingstarted.md
@@ -5,7 +5,7 @@ If you feel, something is missing, please contact us!
 
 ## Requirements
 
-Java > v 17
+PowerSystemDataModel requires Java to be at least Version 21.
 
 ## Where to get
 
diff --git a/src/main/java/edu/ie3/datamodel/io/factory/timeseries/SqlIdCoordinateFactory.java b/src/main/java/edu/ie3/datamodel/io/factory/timeseries/SqlIdCoordinateFactory.java
index 3780069a4..81d7ee963 100644
--- a/src/main/java/edu/ie3/datamodel/io/factory/timeseries/SqlIdCoordinateFactory.java
+++ b/src/main/java/edu/ie3/datamodel/io/factory/timeseries/SqlIdCoordinateFactory.java
@@ -20,13 +20,13 @@
 public class SqlIdCoordinateFactory extends IdCoordinateFactory {
   private static final String COORDINATE_ID = "id";
   private static final String COORDINATE = "coordinate";
-  private final WKBReader reader = new WKBReader();
 
   @Override
   protected IdCoordinateInput buildModel(SimpleFactoryData data) {
     try {
       int coordinateId = data.getInt(COORDINATE_ID);
       byte[] byteArr = WKBReader.hexToBytes(data.getField(COORDINATE));
+      WKBReader reader = new WKBReader();
 
       Coordinate coordinate = reader.read(byteArr).getCoordinate();
 
diff --git a/src/main/java/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchy.java b/src/main/java/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchy.java
index fff633bbe..78d1cbf43 100644
--- a/src/main/java/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchy.java
+++ b/src/main/java/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchy.java
@@ -172,18 +172,6 @@ public void createDirs(boolean withOptionals) throws IOException {
     }
   }
 
-  /**
-   * Gives the {@link #baseDirectory}).
-   *
-   * @return An Option to the base directory as a string
-   * @deprecated Use {@link edu.ie3.datamodel.io.connectors.CsvFileConnector} instead
-   */
-  @Deprecated(since = "3.0", forRemoval = true)
-  @Override
-  public Optional<Path> getBaseDirectory() {
-    return Optional.of(this.baseDirectory);
-  }
-
   /**
    * Gives the correct sub directory (w.r.t. {@link #baseDirectory}) for the provided class.
    *
diff --git a/src/main/java/edu/ie3/datamodel/io/naming/FileHierarchy.java b/src/main/java/edu/ie3/datamodel/io/naming/FileHierarchy.java
index d13e911c8..1c9502f67 100644
--- a/src/main/java/edu/ie3/datamodel/io/naming/FileHierarchy.java
+++ b/src/main/java/edu/ie3/datamodel/io/naming/FileHierarchy.java
@@ -23,13 +23,4 @@ public interface FileHierarchy {
    * @return An Option to the regarding sub directory as a string
    */
   Optional<Path> getSubDirectory(Class<? extends Entity> cls);
-
-  /**
-   * Determines the base directory.
-   *
-   * @return An option to the base directory
-   * @deprecated Use {@link edu.ie3.datamodel.io.connectors.CsvFileConnector} instead
-   */
-  @Deprecated(since = "3.0", forRemoval = true)
-  Optional<Path> getBaseDirectory();
 }
diff --git a/src/main/java/edu/ie3/datamodel/io/naming/FlatDirectoryHierarchy.java b/src/main/java/edu/ie3/datamodel/io/naming/FlatDirectoryHierarchy.java
index eab4b6efd..18dd38621 100644
--- a/src/main/java/edu/ie3/datamodel/io/naming/FlatDirectoryHierarchy.java
+++ b/src/main/java/edu/ie3/datamodel/io/naming/FlatDirectoryHierarchy.java
@@ -22,16 +22,4 @@ public class FlatDirectoryHierarchy implements FileHierarchy {
   public Optional<Path> getSubDirectory(Class<? extends Entity> cls) {
     return Optional.empty();
   }
-
-  /**
-   * Gives the baseDirectory, which is Empty.
-   *
-   * @return An Option to the base directory as a string
-   * @deprecated Use {@link edu.ie3.datamodel.io.connectors.CsvFileConnector} instead
-   */
-  @Deprecated(since = "3.0", forRemoval = true)
-  @Override
-  public Optional<Path> getBaseDirectory() {
-    return Optional.empty();
-  }
 }
diff --git a/src/test/groovy/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchyTest.groovy b/src/test/groovy/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchyTest.groovy
index 8852605c4..d24a56605 100644
--- a/src/test/groovy/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchyTest.groovy
+++ b/src/test/groovy/edu/ie3/datamodel/io/naming/DefaultDirectoryHierarchyTest.groovy
@@ -6,6 +6,7 @@
 package edu.ie3.datamodel.io.naming
 
 import edu.ie3.datamodel.exceptions.FileException
+import edu.ie3.datamodel.io.connectors.CsvFileConnector
 import edu.ie3.datamodel.io.naming.DefaultDirectoryHierarchy
 import edu.ie3.util.io.FileIOUtils
 import org.apache.commons.io.FilenameUtils
@@ -39,13 +40,14 @@ class DefaultDirectoryHierarchyTest extends Specification {
     given:
     def gridName = "test_grid"
     def basePath = basePathString(gridName)
+    def connector = new CsvFileConnector(basePath)
 
     when:
     def dfh = new DefaultDirectoryHierarchy(tmpDirectory, gridName)
 
     then:
     try {
-      dfh.baseDirectory.get() == basePath
+      connector.baseDirectory == basePath
       dfh.subDirectories.size() == 9
       dfh.subDirectories.get(basePath.resolve(Path.of("input", "grid"))) == true
       dfh.subDirectories.get(basePath.resolve(Path.of("input", "participants"))) == true