diff --git a/src/services/appsMetadata.ts b/src/services/appsMetadata.ts
index 320de941..fb489cac 100644
--- a/src/services/appsMetadata.ts
+++ b/src/services/appsMetadata.ts
@@ -4,7 +4,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
-import { Metadata, StudyMetadata } from '../utils';
+import { BaseVoltage, Metadata, StudyMetadata } from '../utils';
 
 // https://github.com/gridsuite/deployment/blob/main/docker-compose/docker-compose.base.yml
 // https://github.com/gridsuite/deployment/blob/main/k8s/resources/common/config/apps-metadata.json
@@ -39,14 +39,21 @@ export function isStudyMetadata(metadata: Metadata): metadata is StudyMetadata {
 
 export async function fetchStudyMetadata(): Promise<StudyMetadata> {
     console.info(`Fetching study metadata...`);
-    const studyMetadata = (await fetchAppsMetadata()).filter(isStudyMetadata);
+    const studyMetadata = (await fetchAppsMetadata()).find(isStudyMetadata);
     if (!studyMetadata) {
         throw new Error('Study entry could not be found in metadata');
     } else {
-        return studyMetadata[0]; // There should be only one study metadata
+        return studyMetadata; // There should be only one study metadata
     }
 }
 
+export async function fetchBaseVoltages(): Promise<BaseVoltage[]> {
+    console.info(`Fetching apps' base voltages...`);
+    const env = await fetchEnv();
+    const res = await fetch(`${env.appsMetadataServerUrl}/apps-metadata-base-voltages.json`);
+    return res.json();
+}
+
 export async function fetchFavoriteAndDefaultCountries(): Promise<{
     favoriteCountries: string[];
     defaultCountry?: string;
diff --git a/src/utils/types/metadata.ts b/src/utils/types/metadata.ts
index f5f1076f..ef0a9110 100644
--- a/src/utils/types/metadata.ts
+++ b/src/utils/types/metadata.ts
@@ -31,3 +31,21 @@ export type StudyMetadata = Metadata & {
     favoriteCountries?: string[];
     substationPropertiesGlobalFilters?: Map<string, string[]>; // used to generate user specific global filters
 };
+
+type ThemeColors = Record<string, string>;
+type SldAndNadColors = {
+    darkThemeColors: ThemeColors;
+    lightThemeColors: ThemeColors;
+};
+
+export type BaseVoltageConfig = {
+    // used when calling powsybl server
+    name: string;
+    minValue: number;
+    maxValue: number;
+};
+export type BaseVoltage = BaseVoltageConfig & {
+    // used to define the voltage ranges and their colors
+    networkMapColor: string;
+    sldAndNadColors: SldAndNadColors;
+};