diff --git a/hoot-core/src/main/cpp/hoot/core/io/ElementStreamer.cpp b/hoot-core/src/main/cpp/hoot/core/io/ElementStreamer.cpp
index 74fb491..ca75f4a 100644
--- a/hoot-core/src/main/cpp/hoot/core/io/ElementStreamer.cpp
+++ b/hoot-core/src/main/cpp/hoot/core/io/ElementStreamer.cpp
@@ -228,6 +228,7 @@ void ElementStreamer::stream(const QStringList& inputs, const QString& out,
std::dynamic_pointer_cast<ElementOutputStream>(writer);
std::shared_ptr<PartialOsmMapWriter> partialWriter =
std::dynamic_pointer_cast<PartialOsmMapWriter>(writer);
+ partialWriter->initializePartial();
for (int i = 0; i < inputs.size(); i++)
{