Our Company

Rangitata Diversion Race Management Ltd

RDRML is a water conveyance company that operates and maintains the Rangitata Diversion Race (RDR) for the benefit of its shareholders who utilise the water for irrigation, hydrogeneration and supply of stockwater.

The RDR is a 67km long canal that stretches beneath (the foothills of) Mid Canterbury from the Rangitata River in the south to the Rakaia River in the north.

Built during the 1940’s depression period, the RDR is recognised as one of the most visionary engineering accomplishments of its time and has helped to shape our region.

Our Management & Operations Team

Tony McCormick

Chief Executive

Tony joined the company in 2019.

Tony’s role is to ensure the safety of the RDR Scheme, the well-being of the staff and the implementation of the company’s Strategic Plan for the prosperity of the region.

He trained originally as a Mechanical Engineer and the initial part of Tony’s career was in electricity generation with NZED/ECNZ and then Contact Energy and Meridian. Over 25 years Tony was involved in both thermal generation (gas, coal, oil and geothermal) and hydro generation – throughout New Zealand and also in Australia for 3 years with Contact Energy.

In 2007 he joined Fulton Hogan and was in their Major Project Group for four years before starting with Opuha Water Ltd as CEO where he relished the opportunity to lead the company through challenging water and electricity times over the next seven years.

Tony’s vision for RDRML is to maintain the great work of his predecessors to provide safe, efficient and reliable water for the prosperity of the region. He is well aware that to achieve this will require some of his engineering and ALL of his relationship skills and experience as he believes maintaining the support of the wider community and key stakeholders is vital to the success of the company.

Wendy Reith

Office Manager

Wendy joined the company in 1998.

Wendy’s role is very diverse and she provides critical support and coordination across our accounts, HR, Board, communication and administration functions. She’s our go-to person for most things!

Cornelius (Kees) Beentjes

Engineering Manager

Kees joined the company in November 2021. 

Kees’ role is to provide assurance on the long-term functionality, security and viability of our infrastructure assets.

Andrew Mockford

Operations Manager

Andrew joined the company in July 2023.

Andrew’s focus is on the safe and compliant operation of the RDR to deliver the water requested by our various water users. Andrew manages a small team of three who are each rostered to provide 24/7 oversight of the RDR. The team coordinates the continuous operation and the day-to-day maintenance required to keep the scheme functioning at its full potential.

Cam Wilson

Operator Maintainer

Cam joined RDRML in March 2022.

Cam’s role is to ensure that all available water is able to be utilised by our various customers by operating the scheme in a safe and compliant manner. He is also a key part of our routine maintenance activities.

Aaron Poyner

Operator Maintainer

Aaron joined RDRML in September 2022.

Aaron’s role as part of our Operations team is to ensure all our customers get the water they’re entitled to and that the scheme is operated and maintained in accordance with our resource consents and operating procedures.

Neill Stevens

Operations Support

Neill joined the company in 1994.

After nearly 29 years at the helm of RDR operations, Neill is still involved with the company in a part- time capacity providing support in several areas including operation of the drag-line (dredge) at the intake and with vegetation control around the extensive scheme area. Retaining access to Neill’s operational experience is still extremely valuable to the team.

Our Board Members

Jen Crawford


Appointed 2021
MHV Water representative

Richard Spearman

Deputy Chair

Appointed 2015
Manawa Energy representative

Neil Brown


Appointed 2016
Ashburton District Council representative

Matt James


Appointed 2023
Manawa Energy representative

Phil Lowe


Appointed 2023
Ashburton Lyndhurst Irrigation representative

Evan Chisnall


Appointed 2022
MHV Water representative

Our Shareholders

RDR Irrigation Schemes and Hydro Stations Plan

Manawa Energy Limited

Manawa Energy own and operate 26 power schemes around New Zealand including Montalto and Highbank Power stations on the RDR.

Ave generation for Montalto 12 GWh

Ave generation for Highbank 94 GWh

Manawa Energy utilise approximately 65% of the RDR water


Ashburton District Council (ADC)

One of ADC’s roles is to supply stockwater, mainly via a dedicated race network*, throughout Mid Canterbury. ADC draws some of its stockwater from the RDR. 

Ashburton District Council utilise approximately 2% of the RDR water

*ADC is working with the irrigation schemes to reduce the extent of its stockwater race network and transition stockwater delivery to the irrigation schemes.


MHV Water Limited

MHV Water is a farmer-owned cooperative that delivers water for the purpose of irrigation through an open race system for over 58 000 hectares of farmland in Mid-Canterbury between the Ashburton and Rangitata rivers.

MHV Water utilise approximately 23% of the RDR water


Ashburton Lyndhurst Irrigation Limited (ALIL)

ALIL is a farmer-owned cooperative that delivers water for the purpose of irrigation through a network of pressurised pipes to enable shareholders to irrigate close to 30,000ha of Mid-Canterbury land.

ALIL utilise approximately 10% of the RDR water


Learn about Our Scheme