diff --git a/schema.graphqls b/schema.graphqls
index 9874720..2823738 100644
--- a/schema.graphqls
+++ b/schema.graphqls
@@ -30,6 +30,7 @@ type ParkingStructure {
   coordinates: Coordinates!
   address: String!
   updatedTime: DateTime
+  systemId: ID!
 
   historicalAverages(input: HistoricalParkingAverageQueryInput): [HistoricalParkingAverageQueryResult!]
 }
diff --git a/src/resolvers/ParkingSystemResolvers.ts b/src/resolvers/ParkingSystemResolvers.ts
index 73a5303..076f18e 100644
--- a/src/resolvers/ParkingSystemResolvers.ts
+++ b/src/resolvers/ParkingSystemResolvers.ts
@@ -11,9 +11,15 @@ export const ParkingSystemResolvers: Resolvers<ServerContext> = {
       const parkingRepository = system.parkingRepository;
       if (!parkingRepository) return [];
 
-      return await parkingRepository.getParkingStructures();
+      const parkingStructures = await parkingRepository.getParkingStructures();
+      return parkingStructures.map((structure) => {
+        return {
+          ...structure,
+          systemId: parent.systemId
+        };
+      });
     },
-    parkingStructure: async (parent, args, contextValue, info) => {
+    parkingStructure: async (parent, args, contextValue, _info) => {
       if (!args.id) return null;
 
       const system = contextValue.findSystemById(parent.systemId);
@@ -23,7 +29,11 @@ export const ParkingSystemResolvers: Resolvers<ServerContext> = {
       const parkingRepository = system.parkingRepository;
       if (!parkingRepository) return null;
 
-      return await parkingRepository.getParkingStructureById(args.id);
+      const parkingStructure = await parkingRepository.getParkingStructureById(args.id);
+      return parkingStructure ? {
+        ...parkingStructure,
+        systemId: parent.systemId,
+      } : null;
     },
   }
 }