The river originates in the Christchurch suburb of Harewood, where the dry swale is intermittently filled with stormwater.

The third suggests that the name was derived from the use of flax sticks stuck in the ground to guide travellers to where the river was bridged by logs.

A 40-year vision for the catchment was developed in the late 1990s, which was based on concerns and opportunities associated with the Styx ecosystem.

After much consultation with the community the Christchurch City Council adopted the "Styx Vision 2000–2040" at its meeting on 11 July 2001.

Christchurch City Council has since acquired large areas of land alongside waterways in the Styx catchment, which will eventually form an ecological network.