diff --git a/guide/age-of-dwarves/src/simulation/simulation.worker.ts b/guide/age-of-dwarves/src/simulation/simulation.worker.ts
index fa29cb02..595089ec 100644
--- a/guide/age-of-dwarves/src/simulation/simulation.worker.ts
+++ b/guide/age-of-dwarves/src/simulation/simulation.worker.ts
@@ -200,6 +200,8 @@ async function prebufferFrames(state: ScenarioState, scenarioId: string, frameCo
           ocean_dead_fraction: snap.ocean_dead_fraction,
           ley_edges: snap.ley_edges,
           wonder_positions: snap.wonder_positions,
+          riverSegments: snap.riverSegments,
+          riverSources: snap.riverSources,
         })
         transferables.push(snap.texA.buffer as ArrayBuffer, snap.texB.buffer as ArrayBuffer, snap.texC.buffer as ArrayBuffer)
       }
@@ -402,6 +404,8 @@ function handleFrame(scenarioId: string, turn: number, lookahead: number): void
       ocean_dead_fraction: snap.ocean_dead_fraction,
       ley_edges: snap.ley_edges,
       wonder_positions: snap.wonder_positions,
+      riverSegments: snap.riverSegments,
+      riverSources: snap.riverSources,
     })
     transferables.push(snap.texA.buffer as ArrayBuffer, snap.texB.buffer as ArrayBuffer, snap.texC.buffer as ArrayBuffer)
   }