140 likes | 381 Vues
Waimea Community Dam (Lee Valley) - Tasman. Irrigation New Zealand Conference – Napier 7 – 10 April, 2014 Murray King Joseph Thomas Waimea Water Augmentation Committee. Lower Waimea River Drought (dry river)& Flood (1500 m3). Background.
E N D
Waimea Community Dam (Lee Valley) - Tasman Irrigation New Zealand Conference – Napier 7 – 10 April, 2014 Murray King Joseph Thomas Waimea Water Augmentation Committee
Background • The Waimea Plains is acutely water short - water rationing 7 out of the last 10 years. • Shortfall 22 – 70% (~600 – 1900 l/s) depending on what the low flow requirements in the Waimea River are set at. • Committee (WWAC) brief “To find a solution to acute water shortage on the Waimea Plains” • Limited high value land • Diverse land use • Long irrigation history • Well understood water resource • A multifunction dam proposed
The Proposed Scheme Concrete faced rockfill dam (CFRD) Size of reservoir 13.4 million m3 Lake size 65.9 ha Dam height 52 m Construction time ~2 years Est. cost @ 2009 (excl hydro) ~ $42 million* *Cost likely higher when CCI and final design/peer work completed – also subject to final tender price Time to fill 1 -3 months Irrigable area 5850 ha(eq.) Tasman(now/future) 1400 ha (eq) Future Regional 515 ha (eq)
Scheme Ownership Structure • Scheme would be owned by water users (community-owned co-operative scheme) • Operated on a cost recovery basis • Proportion of cost should be borne by community as a whole to cover the environmental flows (incremental cost of building a larger scheme) – 30% • Other costs shared between users on basis of water demand
Where are we • Regional Plan progressed since late 2012 Dam & No dam Option provided & Hearing completed late 2013 • Commissioners decision notified in early March 2014 – important benchmark re no dam restrictions – significant water cuts kick in 15/16 if no dam - cuts up to 50 % every year and more beyond this - EDA findings next slide • Consent preparation underway – 95 % complete, prelodgement/lodgement of consent ~ April 2014
EDA - GDP Findings – Cost of No Augmentation This equates to GDP of $800,000 per hectare over 25 years
Design • Detailed design 85 % complete • Hold until consent notified and any relevant submission evaluated • Complete detailed design and tender • Using rating mechanism require SCP and LTP planned 2014/2015
Challenges • Both Regional Plan and Consents – Statutory processes • Consents – agreement on mitigation • Land acquisition • Timing SCP/LTP – Political • Funding vs. financing – sources/options/CII • Efficient tender and costing