Environment Canterbury

RIV_2600315 Rangitata River, Arundel Investigation and Flood Risk Option Modelling

Canterbury Regional Council (CRC) has a responsibility to manage flood
protection, land drainage and erosion control works across the Canterbury
region including for the Rangitata River Control Scheme.
Rangitata South Irrigation Ltd (RSIL) who operate a standalone irrigation
system has regionally significant infrastructure located at Arundel including
intake and control structures and 7 large water storage ponds.
Both CRC and RSIL have undertaken preliminary design investigation on
improvements to flood protection at Arundel. These strategies included the use
of stopbanks to divert water back into the Rangitata river upstream of the
Rangitata River bridge. However, modelling and past event evidence has
identified that the Rangitata bridge has limited flood capacity that prevents a
number of options for the improvement of Arundel flood resilience.
The bridge, the irrigation intake, storage ponds, flood protection and
neighbouring property assets are all closely inter-related with the dynamically
changing nature of the river and flood events that occur at this location.
A coordinated approach to evaluating and designing upgrades to these assets
is required.

Department/Business Unit: Finance