Casey won a John R. Freeman fellowship from the American Society of Mechanical Engineers in 1933 to study hydraulics and civil engineering in Germany. For the next two years, he attended the "Technische Hochschule" in Berlin, earning a Doctorate in Engineering. His thesis, written in German, was on "Geschieb Bewegung", the bedload movement in streams. Returning to the United States in June 1935, Casey was posted to Eastport, Maine as chief of the Engineering Division at the Passamaquoddy Tidal Power Project, a New Deal public works project. There, he established a concrete testing laboratory under Charles E. Wuerpel which is now part of the Structures Laboratory at the Waterways Experiment Station at Vicksburg, Mississippi. Due to political forces, the project came to nothing and was allowed to die. After the Passamaquoddy project fell through, Casey served with the Boston Engineer District on flood control surveys of the Connecticut River Valley.