diff --git a/webapi/src/main/resources/knora-ontologies/knora-base.ttl b/webapi/src/main/resources/knora-ontologies/knora-base.ttl
index 3b341827d8..910c3492c6 100644
--- a/webapi/src/main/resources/knora-ontologies/knora-base.ttl
+++ b/webapi/src/main/resources/knora-ontologies/knora-base.ttl
@@ -19,7 +19,7 @@
     rdf:type           owl:Ontology ;
     rdfs:label         "The Knora base ontology"@en ;
     :attachedToProject knora-admin:SystemProject ;
-    :ontologyVersion   "knora-base v29" .
+    :ontologyVersion   "knora-base v30" .
 
 
 #################################################################
diff --git a/webapi/src/main/scala/org/knora/webapi/package.scala b/webapi/src/main/scala/org/knora/webapi/package.scala
index bad29dc045..3c51e25537 100644
--- a/webapi/src/main/scala/org/knora/webapi/package.scala
+++ b/webapi/src/main/scala/org/knora/webapi/package.scala
@@ -11,7 +11,7 @@ package object webapi {
    * The version of `knora-base` and of the other built-in ontologies that this version of Knora requires.
    * Must be the same as the object of `knora-base:ontologyVersion` in the `knora-base` ontology being used.
    */
-  val KnoraBaseVersion: String = "knora-base v29"
+  val KnoraBaseVersion: String = "knora-base v30"
 
   /**
    * `IRI` is a synonym for `String`, used to improve code readability.
diff --git a/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/RepositoryUpdatePlan.scala b/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/RepositoryUpdatePlan.scala
index f9fb9437c8..37994a324f 100644
--- a/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/RepositoryUpdatePlan.scala
+++ b/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/RepositoryUpdatePlan.scala
@@ -8,6 +8,7 @@ package org.knora.webapi.store.triplestore.upgrade
 import com.typesafe.scalalogging.Logger
 
 import org.knora.webapi.messages.store.triplestoremessages.RdfDataObject
+import org.knora.webapi.store.triplestore.upgrade.plugins.UpgradePluginPR3110
 import org.knora.webapi.store.triplestore.upgrade.plugins.*
 
 /**
@@ -64,6 +65,7 @@ object RepositoryUpdatePlan {
       PluginForKnoraBaseVersion(versionNumber = 27, plugin = new MigrateOnlyBuiltInGraphs), // PR 3026
       PluginForKnoraBaseVersion(versionNumber = 28, plugin = new MigrateOnlyBuiltInGraphs), // PR 3038
       PluginForKnoraBaseVersion(versionNumber = 29, plugin = new UpgradePluginPR3110()),
+      PluginForKnoraBaseVersion(versionNumber = 30, plugin = new UpgradePluginPR3111()),
       // KEEP IT ON THE BOTTOM
       // From "versionNumber = 6" don't use prBasedVersionString!
     )
diff --git a/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/plugins/UpgradePluginPR3111.scala b/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/plugins/UpgradePluginPR3111.scala
new file mode 100644
index 0000000000..9999e5031f
--- /dev/null
+++ b/webapi/src/main/scala/org/knora/webapi/store/triplestore/upgrade/plugins/UpgradePluginPR3111.scala
@@ -0,0 +1,39 @@
+/*
+ * Copyright © 2021 - 2024 Swiss National Data and Service Center for the Humanities and/or DaSCH Service Platform contributors.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.knora.webapi.store.triplestore.upgrade.plugins
+
+import org.eclipse.rdf4j.sparqlbuilder.core.SparqlBuilder.`var` as variable
+import org.eclipse.rdf4j.sparqlbuilder.core.query.ModifyQuery
+import org.eclipse.rdf4j.sparqlbuilder.core.query.*
+import org.eclipse.rdf4j.sparqlbuilder.rdf.Rdf
+
+import org.knora.webapi.slice.admin.AdminConstants
+import org.knora.webapi.slice.admin.repo.rdf.Vocabulary
+import org.knora.webapi.store.triplestore.upgrade.GraphsForMigration
+import org.knora.webapi.store.triplestore.upgrade.MigrateSpecificGraphs
+
+/**
+ * Certain restricted views have a watermark that is not a boolean. This plugin removes the invalid watermark triples.
+ */
+class UpgradePluginPR3111 extends AbstractSparqlUpdatePlugin {
+
+  override def graphsForMigration: GraphsForMigration =
+    MigrateSpecificGraphs.from(AdminConstants.adminDataNamedGraph)
+
+  private val removeInvalidRestrictedViewWatermarkTriples: ModifyQuery = {
+    val invalidTriple = variable("s").has(
+      Vocabulary.KnoraAdmin.projectRestrictedViewWatermark,
+      Rdf.literalOf("path_to_image"),
+    )
+    Queries
+      .MODIFY()
+      .prefix(Vocabulary.KnoraAdmin.NS)
+      .delete(invalidTriple)
+      .where(invalidTriple.from(Vocabulary.NamedGraphs.knoraAdminIri))
+  }
+
+  override def getQueries: List[ModifyQuery] = List(removeInvalidRestrictedViewWatermarkTriples)
+}