Adriaan Moorrees, surveyor, was the son of Hubertus Adrianus Moorreess, a cleric of the Dutch Reformed Church, and his wife Maria Magdalena de Vaal. Adriaan studied at the South African College, Cape Town, from 1862 to 1865. One of his cousins, also named Adriaan Moorrees (1855-1938), studied there from 1870 to 1874, obtained the Third-class Certificate of the Board of Public Examiners of the Cape of Good Hope (equivalent to matriculation) in 1873, and later became professor of theology at Stellenbosch.
Adriaan the surveyor was admitted to practice as a land surveyor in the Cape of Good Hope in 1870. By 1877 he was a well-known surveyor in Tulbagh, and that year took J.J. Bosman* as a junior partner. They practiced under the name Moorrees and Bosman, and were entrusted with several large surveys by the Cape government, including one carried out by Bosman in British Bechuanaland (now part of the Northern Cape, between approximately 28oS and the Botswana border). The results of that survey were incorporated in the geodetic survey of southern Africa, and used in the compilation of a new map of the Cape Colony by the surveyor-general's office around 1896. The firm was dissolved in 1892, when Moorrees was appointed surveyor-general of British Bechuanaland. However, he died the next year.