The development of HHCode can be traced to efforts in the 1990's by Edric Keighan, Panagiotis A. Vretanos, Michael Galluchon, and Herman P. Varma while working for the Canadian Hydrographic Service's Atlantic regional offices at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia.
[1] CHS scientists reportedly conceptualized a spatio-temporal indexing system during a hydrographic survey onboard CCGS Hudson on Georges Bank during the summer of 1989.
The indexing system involved an adaptation of a Riemannian hypercube data structure, invoking a helical spiral through 3-dimensional space, which allowed for n-size of features.
The actual implementation of the proposed indexing system was termed a helical hyperspatial code and it was first used by modifying an installation of the Oracle database version 4.
The HHCode comprises a form of space filling curve and the concept was published by the CHS scientists in the International Hydrographic Review.