A man walks on the sandbank by the wreckage of a WWII German warship in front of Djerdap II, a large dam on the Danube River, near Prahovo, Serbia, on Tuesday. Water levels on the Danube River, the second-longest in Europe, have dropped so low because of drought that the hulks of dozens of World War II German battleships are emerging into view. The Danube’s record-low water levels have also forced power plants to the brink of shutting down, and governments across Central and Eastern Europe are taking steps to conserve electricity. AdvertisementNow, however, authorities are trying to keep traffic flowing on the Danube, which flows through 10 nations, as the dropping water levels create dangerous conditions. Krsta Brandic, a Prahovo resident, said the low water levels have almost stopped ship traffic: “As you can see, the [big] ships can’t pass anymore.”