In 1910 von Heidenstam was appointed chief engineer of the Shanghai Commission for Port and River and worked there until 1926.
He passed mogenhetsexamen in 1901[1] and after graduating from the Royal Institute of Technology in 1905, he became a reserve officer at the Fortification (Fortifikationen) the same year.
It turned out, however, that independent consulting engineers was unable to assert itself in competition with the financially strong construction companies that dominated the state and municipal construction activity in China and Japan, but von Heidenstam's expert entries in China's then current water issues resulted in his appointment as chief engineer at the international flood control department in Shanghai.
[2] During the years 1918-1922 the Swedish Hydraulic Engineering Company conducted, in cooperation with von Heidenstam, extensive communications technical studies on the expansion of Shanghai's port and its importance for world trade.
The connection between these three men led in 1925 to an agreement on future cooperation between the Swedish Hydraulic Engineering Company and Palmer with von Heidenstam as common representative in London.
[2] von Heidenstam was Sweden's representative in the International Oder Commission from 1930 to 1937 and in the League of Nations Advisory Commission for Communications from 1930 to 1931 and the same for the control of the opium trade from 1934 to 1936. von Heidenstam became a lieutenant in the Road and Waterway Construction Service Corps in 1911 and was later promoted to captain in 1918, to major in 1928 and to lieutenant colonel in 1936.