An update on the Klondyke Proposal 

Rangitata  Diversion  Race  Management  Limited  (‘RDRML’)  continues  to  advance  the  resource  consent  applications necessary for a water storage facility to supplement the Rangitata Diversion Race (‘RDR’). 

Investigations by the RDRML over the past four years have assessed a variety of options relating to water storage  capacities,  ranging  from  5  million  cubic  metres  to  100  million  cubic  metres.    The  investigations  included preliminary engineering and technical assessments of each option.

Of note is that while emphasising the need to carefully consider and advance the water storage proposal, none of the work that has been completed identified a fatal flaw in the proposal.

Preliminary  consultation  with  stakeholders  and  interested  parties  has  taken  place  over  the  past  12  months. Two community information events were publicly advertised and held in May 2015. This consultation and investigations undertaken by a team of respected environmental experts guided RDRML in its decision that the option of a 53 million cubic metres water storage facility is the most favourable.

In summary, the water storage facility will:

  1. Improve the irrigation reliability for RDRML’s existing shareholders taking water from the RDR, and supply sufficient water to enable further irrigation in Mid-­‐Canterbury and / or enable the RDRML to refocus the existing take such that users in South Canterbury can also abstract water from the RDR;
  2. Provide  a  physical  tool  to  assist  in  achieving  Regional  water  targets  and  outcomes  by  artificial recharge of groundwater by using Managed Aquifer Recharge / Targeted Steam Augmentation;
  3. Be located on the river terraces at the upstream end of the RDR, with the Rangitata River to the west, Ealing Montalto Road to the east, and farmland south of Shepherds Bush Road to the south. A location plan is provided within this information pack on page 4;
  4. Have  a  total  construction  area  of  approximately  500  hectares  of  land,  including  the  storage  facility (286 hectares), temporary works, spoil disposal and pond outlet areas, that currently supports agricultural endeavour;
  5. Be  supported  by  a  supplementary  water  take  of  up  to  10  cubic  metres  per  second  from  the  same location as the existing RDR consented take from the Rangitata River. This take flow, which will be in addition to the existing operational takes, will only be taken during periods of flood flows;
  6. Require the existing RDR canal to be widened and raised in height between the intake and the water storage facility to convey the supplementary water take and in accordance with the approach set out by the Rangitata Water Conservation Order, as illustrated in the Canal Modification Plan within this information pack on page 5;
  7. Construct earth embankments that range from 2.5 metres in height to a maximum of 30.5 metres. The water storage facility will have a maximum water depth of 24 metres;
  8. Require  approximately  11  million  cubic  metres  of  excavated  material,  of  which,  10  million  cubic metres will be used during construction. 1 million cubic metres of surplus material will be spread across disposal areas to the north and south of the pond;
  9. Be lined with synthetic material so that any impounded water does not leak through the porous soils that underlie the footprint of the water storage facility;
  10. Be constructed over a period of approximately five years. Construction methodology plans prepared by MWH are included within this information pack on page 6; and
  11. Contain an outlet at the southern end of the storage pond that conveys flow to the Mayfield Hinds Irrigation canal, which has been designed to include a recreational kayak course that is available for public use.  A preliminary example of the kayak course is also set out on the plans included within the downloadable information pack on page 8.

Where to from here?

Now that the preferred option has been selected, the RDRML wish to lodge a resource consent application in mid-­‐2016.

To  inform  the  resource  consent  application  the  RDRML  has  commissioned  a  significant  number  of  independent technical assessments. Table A, which follows, sets out the assessments and their respective experts (authors). Each of the assessments will be available for public view on request from the RDRML and posted on this website.

Further information:

Download full Klondyke information pack for April 2016