23 rd June 2016 Meeting held at Fonterras Jordan Valley Farm 1000 - - - PowerPoint PPT Presentation

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23 rd June 2016 Meeting held at Fonterras Jordan Valley Farm 1000 - - - PowerPoint PPT Presentation

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Hikurangi Swamp Working Group Meeting 23 rd June 2016 Meeting held at Fonterras Jordan Valley Farm 1000 - 1200 Agenda Topic/Owner Information 1 Last Meeting Minutes 2 Pocket Representation Tanekaha Pocket Representative 3

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Hikurangi Swamp Working Group Meeting

23rd June 2016

Meeting held at Fonterra’s Jordan Valley Farm 1000 - 1200

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Agenda

Topic/Owner Information 1 Last Meeting Minutes 2 Pocket Representation Tanekaha Pocket Representative 3 Operations/Maintenance (January to May) 1. Monthly Overviews from Hydrotech 2. Pump Availability 3. Power Usage 4. Pump Operation 5. New Signage 6. Maintenance Activities (Photographs)

  • Bermland Spraying
  • Maruarua Stream Rapids Removal
  • Jack’s Swale
  • Tanekaha Weed Screen
  • Weed Screen Clearing Excavator Pads

4 Finances Hydrotech Monthly Finance Review OPEX 2015/16 OPEX 2016/17 2016/17 Drain Clearing Budget & Discussion 5 Environment NIWA’s eel monitoring study Tanekaha Drain Fencing Tanekaha Ox-bow Restoration Okarika Ox-Bow Restoration 6 Level of Protection Option for Enhanced Protection - Original Scheme Part 2 7 Objectives Short, Medium & Long Term Objectives 8 AOB

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Pocket Representation – Tanekaha Pocket Representative

  • Tanekaha no longer has a pocket

representative

  • Suggestions?
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Operations and Maintenance – Overview

  • f HydroTech’s January Report
  • Fairly dry month with an extended rain

event which lasted 3 – 4 days

  • Rain distribution was uneven, with

Okariki River remaining low whilst Ngararatunua, Te Mata & Otonga saw rising river levels

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SLIDE 5

Operations and Maintenance – Overview

  • f HydroTech’s February Report
  • Month was mostly wet with a couple of

dry periods

  • Panel Tech undertook the concrete

repairs at Ngararatunua during the dry spells

  • Soda block removals were underway
  • n the Maruarua Stream
  • Storm in the middle of the month saw

most of the pump stations operating

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Operations and Maintenance – Overview

  • f HydroTech’s March Report
  • Weather was quite wet, with a storm in

the first week of the month, a second storm later in the month missed the Hikurangi Catchment

  • Quarterly maintenance checks were

undertaken across all the stations and eel monitoring equipment was installed at Mountain Pump Station.

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Operations and Maintenance – Overview

  • f HydroTech’s April Report
  • April was settled with only a couple of

rain events causing a number of pumps to operate

  • Lambert Drain’s flood gate was

damaged as it was forced to operate against a high river

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Operations and Maintenance – Overview

  • f HydroTech’s May Report
  • May was dry, with only ca couple of

rainfall events, but nothing large enough to cause pumps to operate.

  • Safe excavator operating pads have

been installed at the pump stations and NIWA have continued monitoring with the release of tagged eels.

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Operations/Maintenance - Pump Availability January to May

Station

~1.1 m3/s Pumps ~ 4.1 m3/s Pumps

Station Capacity (m3/s) A B C D E Otonga Flygt (17%) Flygt (17%) Pleuger (65%) 6.3 Te Mata Pleuger (17%) Flygt (17%) KSB (65%) 6.3 Mountain Pleuger (50%) KSB (50%) 2.2 Tanekaha McKewen (50%) Pleuger (50%) 2.2 Junction Pleuger (100%) 1.1 Ngararatunua Pleuger (11%) Pleuger (11%) Pleuger (39%) Pleuger (39%) 10.4 Okarika Pleuger (10%) Pleuger (10%) Pleuger (10%) Pleuger (35%) Pleuger (35%) 11.5

One large & one small spare Pleugers available in storage There was 100% pump availability across the Scheme for the whole January to May period. A small number of pumps were temporarily isolated during good weather for vortex board replacements, flow straightener replacements and concrete repairs to the pump bay walls

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Operations/Maintenance - Power Usage

  • 10000

10000 20000 30000 40000 50000 60000 70000 80000 90000 100000 Swamp Power Cost 2012/13 Swamp Power Cost 2013/14 Swamp Power Cost 2014/15 Swamp Power Cost 2015/16 Swamp Power Cost Month/Year 2012/13 2013/14 2014/15 2015/16 August 730 89095 3000 September 30404 5083 26787 5481 October 30179 16498 47467 10255 November 15947 10183 1901 615 December 10773 1217 621 518 January 781 243 23535 299 February 2374 3479 551 1790 March 2293 833

  • 209

5583 April 18 246 501 May 331 1412 591 June 997 2503 2199 July 25065 1178 2199 Annual Total 119892 42875 195238 27541

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HydroTech January Report Review – Pump Hours Run

Pump Pocket

Junction Te Mata Tanekaha Mountain Otonga Ngararatunua Okarika

A 23 19 3 B 4 3 11 44 29 C D 2 E 2

A, B & C are small (~1.1m3) pumps, D & E are the larger (~4.1m3) pumps

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HydroTech February Report Review – Pump Hours Run

Pump Pocket

Junction Te Mata Tanekaha Mountain Otonga Ngararatunua Okarika

A 14 7 18 41 44 62 B 74 9 44 35 48 68 C 59 D 16 20 35 E 9 19

A, B & C are small (~1.1m3) pumps, D & E are the larger (~4.1m3) pumps

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HydroTech March Report Review – Pump Hours Run

Pump Pocket

Junction Te Mata Tanekaha Mountain Otonga Ngararatunua Okarika

A 89 30 45 51 47 73 B 102 6 62 81 47 77 C 28 D 14 12 17 E

A, B & C are small (~1.1m3) pumps, D & E are the larger (~4.1m3) pumps

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HydroTech April Report Review – Pump Hours Run

Pump Pocket

Junction Te Mata Tanekaha Mountain Otonga Ngararatunua Okarika

A 55 9 19 20 B 33 52 13 C D E

A, B & C are small (~1.1m3) pumps, D & E are the larger (~4.1m3) pumps

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HydroTech May Report Review – Pump Hours Run

Pump Pocket

Junction Te Mata Tanekaha Mountain Otonga Ngararatunua Okarika

A B 10 C D E

A, B & C are small (~1.1m3) pumps, D & E are the larger (~4.1m3) pumps

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Bermland Spraying

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Maruarua Stream Rapids Removal

Length of drain cleared of rapids Old river loop which has been filled with excavated material

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Maruarua Stream Rapids Removal - Before

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Maruarua Stream Rapids Removal - After

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Maruarua Stream Rapids Removal - Disposal

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Jack’s Swale

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Jack’s Swale - Before

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Jack’s Swale

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Tanekaha Screen Replacement - Before

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Tanekaha Screen Replacement - After

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Weed Screen Clearing Pads - Before

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Weed Screen Clearing Pads - Before

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Weed Screen Clearing Pads - After

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Weed Screen Clearing Pads - After

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Weed Screen Clearing Pads - After

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HydroTech January Report Review - Finances

Inspection Maintenance Environmental Flood Attendance Drain Clearing

$2,638.24 $10,516.19 $171.49 $483.01

  • Inspections

Preliminary & General (Monthly Checks) Maintenance Replace cable sleeve & bracket Vortex board materials Pump bay access ladder repairs New flow straightener Install pads for weed clearing excavator Environmental Purchase spat ropes Weed control in restored ox-bows Flood Attendance 6 visits including use of excavator

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HydroTech February Report Review - Finances

Inspection Maintenance Environmental Flood Attendance Drain Clearing

$2,638.22 $10,886.30 $806.84 $1480.45 $35,598.95

Inspections Preliminary & General (Monthly Checks) Maintenance Concrete wall repairs at Ngararatunua Station Rust treatment on Pleugers Installation of vortex board Replace pump bay access ladders Installation of flow straightener Environmental Collection and preparation of spat ropes Assist NIWA with eel monitoring equipment installation Padlock and chain for ox-bow gates Grating modifications for eel monitoring equipment installation Flood Attendance 11 visits including use of excavator Drain Clearing Ngararatunua pocket cleaning and Maruarua Stream rapids removal

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HydroTech March Report Review - Finances

Inspection Maintenance Environmental Flood Attendance Drain Clearing

$3,379.52 $18,009.14 $2.371.21 $1.233.14 $59,037.08

Inspections Preliminary & General (Monthly Checks) & Quarterly checks Maintenance Replace corroded washes on handrails Install pads for weed clearing excavator Replace pump bay access ladders Installation of flow straightener Re-galvanize grates Fabricate flow ring replacement Fabricate flow straightener Environmental Assist NIWA with eel monitoring equipment installation Flood Attendance 19 visits including use of excavator Drain Clearing Clearing drains in Okarika Pocket Installing Jack’s Swale Additional work on Maruarua Stream Rapids Removal Riparian Spraying

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HydroTech April Report Review - Finances

Inspection Maintenance Environmental Flood Attendance Drain Clearing

$2,727.60 $2,821.88 $1296.56 $209.81 $11,187.41

Inspections Preliminary & General (Monthly Checks) Maintenance Repair Lambert flood gate winch and post Pump down pump bay and lock out Galvanize flow straightener Tomo investigation at Mountain Station Environmental Assist NIWA with eel monitoring equipment installation Installing power supply for electric eel barrier Flood Attendance 2 visits Drain Clearing Clearing Lambert Drain of dead weeds Maruarua Stream Rapids removal additional work

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HydroTech May Report Review - Finances

Inspection Maintenance Environmental Flood Attendance Drain Clearing

$2,727.60 $7,104.71 $216.11 $131.13

  • Inspections

Preliminary & General (Monthly Checks) Maintenance Spillway mowing Investigate & resolve pump tripping fault Replaced faulty level probe Install flow straightener Install pads for weed clearing excavator Environmental Monitoring eel monitoring equipment for NIWA Flood Attendance 3 visits (no excavator required)

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Finances – OPEX 2015/16

*1 Forecast likely to be lower then this, possibly $45-50k total for the year *2 This includes the $100k on drain clearing, as well as Maruarua Rapids, Jack’s Swale & Environmental

Account Description 2015/16 Actuals YTD 2015/16 Budget Full Year 2015/16 Forecast Other Rentals Received (54,179) (42,594) (60,901) Telephone and Other Communication 3,740 4,080 Electricity Supply Costs 37,885 184,500 80,554*1 Health & Safety Compliance 5,000 Water Rights Paid NRC Consent 799 2,050 799 Payments to External Contractors*2 260,206 170,000 267,723 Legal Fees 1,728 10,000 2,428 Other Professional Fees 11,774 3,000 9,620 Infrastructure & Services (not Contract) 60,000 Plant & Equip Maintenance non Contract 24,641 90,000 30,641 Grand Total 286,593 481,956 334,943

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Finances – OPEX 2016/17

Account Description 2015/16 Forecast 2015/16 Budget 2016/17 Budget Other Rentals Received (60,901) (42,594) (60,085) Telephone and Other Communication 4,080 4,200 Electricity Supply Costs 80,554 184,500 188,190 Signs 500 Health & Safety Compliance 5,000 5,100 Water Rights Paid NRC Consent 799 2,050 2,091 Payments to External Contractors 267,723 170,000 260,645 Legal Fees 2,428 10,000 5,000 Engineering Fees 10,000 Other Professional Fees 9,620 3,000 10,328 Infrastructure & Services (not Contract) 60,000 Plant & Equip Maintenance non Contract 30,641 90,000 88,000 Grand Total 334,943 481,956 513,969

Proposal is to manage the budget to aim to be $100k under budget for the year, whilst maintaining 100% pump availability and proactive maintenance

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Finances - 2016/17 Drain Clearing Budget

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2016/17 Drain Clearing Discussion

  • Open to floor for discussion, however points to note;
  • Budget is $102k
  • Possible further works required on Maruarua Stream
  • There are approx. 88km of drain
  • Cost for spraying is ~$0.23/meter
  • Cost for excavator is ~$2.50/meter
  • The break down for 2015/16 was;
  • 16,171m of spray = $3,719
  • 16,757m of excavation = $40,719
  • Jack’s Swale, Maruarua Rapids, Riparian Spay = $60k
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Environmental – Eel Monitoring

  • NIWA installed the monitoring equipment, electric

fish barrier and released 60 tagged migrant eels at Mountain Pump Station between February & May

  • Number of eels have been detected passing

through the station

  • Report expected sometime over next couple of

months

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Environmental – Tanekaha Drain Fencing

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Environmental – Tanekaha Drain Fencing

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Environmental – Tanekaha Drain Fencing

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Environmental – Tanekaha Ox-Bow

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Environmental – Tanekaha Ox-Bow

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Environmental – Okarika Ox-bow Restoration

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Environmental – Okarika Ox-bow Restoration

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Environmental – Okarika Ox-bow Restoration

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Three weeks ago

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Likely location of ephemeral wetlands in 1942 that we are trying to re-create

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Adjacent area showing what the area was like before we started. 9/06/2016

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New vehicle access way cut into stopbank to allow 4x4 access (to get plants in & out, pest control & weed spraying) Photo 1 9/06/2016

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Drain along the eastern boundary of the site has had all the vegetation and topsoil removed to be spread in the newly formed wetlands later. The drain will be back filled with clay taken to form the wetlands Photo 2 9/06/2016

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Excavator working at the eastern end of the northern wetland. Northern end of the drain has been filled in with clay and groundwater dam installed Topsoil that has been pulled back, awaiting re-spreading in the wetland when the underlying clay has been extracted to provide the depth Clay that has been extracted from the wetland to provide the depth of the wetland, (it will be disposed on in drain or spread across the rest of the elevated sections of the site) Photo 3 9/06/2016

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Excavator working at the eastern end of the northern wetland. Water already accumulating in the western end of the northern wetland with just the top soil removed, clay removal to provide the depth still to be done Clay from the bottom of the wetland still to be removed Top soil pulled back from the wetland, awaiting spreading once clay removed Photo 4 9/06/2016

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Excavator working at the eastern end of the southern wetland. Clay already extracted from the wetland, with the associated depression in the wetland. Top soil pulled back from the wetland, awaiting spreading once clay removed Water already accumulating in the southern wetland with just the top soil removed, clay removal to provide the depth still to be done Photo 5 9/06/2016

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Water already accumulating in the southern wetland with just the top soil removed, clay removal to provide the depth still to be done Remnants of the outline marker put down to indicate to the excavator

  • perators the extent of the wetland

All efforts are being made to preserve all native (particularly woody) vegetation) along the edge

  • f the wetlands

Photo 6 9/06/2016

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Photo 7 10/06/2016 Water depth settled between 100 & 250mm where clay removed and topsoil replaced, clay still to be removed Clay still to be removed

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Photo 8 Topsoil and vegetation removed from wetlands prior to re-spreading, note the tea tree which have been saved (not buried) where possible Mounds of topsoil (left) & clay (right) still to be spread/disposed 10/06/2016

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Photo 9 Final wetland beginning to take shape, no straight lines, uneven depths, no compacted soils 10/06/2016

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Photo 10 Final wetland beginning to take shape, no straight lines, uneven depths, no compacted soils 10/06/2016

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Clay being loaded into the dumper for transportation to infill the drain Photo 11 10/06/2016

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Photo 12 The northern end of the drain has been blocked with a groundwater dam and then all the compacted topsoil from years of grazing has been completely turned over 10/06/2016

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Photo 13 The drain is being filled in with clay (prior to compacting & topsoiling) to remove the function of the drain and assist with raising the groundwater level for the site 10/06/2016

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Photo 14 The southern end of the drain which is still awaiting infilling, the level of the water in the drain can be seen to have risen since the lower half has been in filled (even prior to it being compacted) 10/06/2016

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Photo 15 Elevated view of the northern wetland, with the mounds of clay to be removed and topsoil still to be spread 10/06/2016

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Photo 16 Elevated view of the northern wetland, mounds of clay have been removed and topsoil has been spread 12/06/2016

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Photo 17 Drain being filled in with clay excavated from the wetlands 12/06/2016

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Photo 18 Completed wetlands with topsoil spread and tea tree re-instated 12/06/2016

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Photo 19 One of three locations where the topsoil has been scrapped back on a high section of the site. The surplus clay will then be spread on this area and covered by the topsoil which was pulled back. Surplus clay mounds Scrapped back topsoil Area cleared of topsoil where surplus clay is to be spread and then recovered with topsoil 12/06/2016

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One of three locations where the topsoil has been scrapped back on a high section of the site and surplus clay has been spread, just awaiting covering with the scrapped back topsoil. Photo 20 Scrapped back topsoil awaiting re-spreading

  • n the surplus clay

Area cleared of topsoil and surplus clay has been spread 12/06/2016

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Photo 21 The northern wetland nearing completion, with

  • nly the mounds on the left still to be processed

12/06/2016

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Snags being collected from adjacent bermland (trees are tea tree which had been sprayed by helicopter a few months previous) Photo 22 15/06/2016

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Snags being delivered to site, four bundles in total were collected as well as a number of large logs which had been washed down the river onto the adjacent bermland Photo 23 15/06/2016

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Last section of the drain to be filled, note how the water level in the drain has increased since photographs 2 & 14, indicating the higher water table across the site as a result of the groundwater dam installation and filling of the lower section of the drain Photo 24 15/06/2016

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The completed southern wetland on the right, with the surplus clay being spread and covered with topsoil on the left Photo 25 15/06/2016

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The completed northern wetland on the right, with the last mounds of clay & topsoil on the left Photo 26 15/06/2016

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The most northern point of the completed northern wetland with the first of the snags installed Photo 27 15/06/2016

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Photo 28 The completed northern wetland, complete with snags 16/06/2016

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Photo 29 The paddock between the two wetlands which had had the remaining topsoil turned over to undo the compaction damage from years of grazing 16/06/2016

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Photo 30 The drain has been completed filled in with the surplus clay from the wetlands and covered with topsoil 16/06/2016

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Photo 31 The completed southern wetland, complete with snags 16/06/2016

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Photo 32 The completed southern wetland, complete with snags 16/06/2016

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Estimated final extent of the created ephemeral wetlands ~8,600m2

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Option for Enhanced Protection – Original Scheme Part 2

  • The Hikurangi Swamp Working Group (as one of the

medium term objectives) requested that WDC looks into a historical issue that goes back as far as the conception and installation of the original Hikurangi Swamp Scheme. Essentially it was part 2 of the scheme which was proposed but never implemented due to costs.

  • Part 2 of the Scheme was to cut down the rock which

makes up the bed of the river between Mangere Rapids to just upstream of Lewis Bridge, as shown the area indicated

  • n the map below. The thought behind this is that it would

allow for greater discharge from the bottom of the scheme which is presently limited to approx. 280 cumsecs; the height at which the stopbanks on the scheme overtop.

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Option for Enhanced Protection – Original Scheme Part 2

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Option for Enhanced Protection – Original Scheme Part 2

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Short Term Objectives (Page 1 of 2)

  • To meet all the terms of the resource consent

Completed, complying with all consent conditions

  • Survey the berm land to understand the height variation/ restrictions

down through the swamp Completed, all restrictions noted on tour removed removed

  • Address the issue with the large trees/ significant undergrowth in the

berm land to the immediate SW of Otonga PS Not completed, money used for Jack’s Swale

  • Assess the restrictive influence of the old road formation below the

Jordan Valley Bridge Completed – formation removed

  • Assess the condition and understand the possibility of clearing

restrictions on the Wairua River downstream of the Matarua Bridge Response obtained from NRC, discussion?

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Short Term Objectives (Page 2 of 2)

  • Assess the channel profile (presently pools and riffles) between

the Jordan valley Bridge and Matarau Bridge in the Wairua River Not completed, money used for Jack’s Swale

  • Consider the possibility of trading off ox-bow within the berm

land with ox-bows on private land on the pocket-side of the stopbanks to aid smooth flow through the scheme whilst maintaining the environmental balance. Completed, active environmental restoration projects ongoing in pocket sides only

  • Lock down the date at which the scheme becomes debt free

Completed, Long Term Plan indicated debt free by end of 2025, (subject to weather & pump fails)

  • Investigate external sources of funding for environmental

improvements within the pockets Completed, working in conjunction with Living Water

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Medium Term Objectives (1 – 5 years)

  • Spillway monitoring and spillway / stop bank alterations (if

required) Ongoing activity, undertake survey in next 3 – 4 years and assess data from next 5 compatible flood events

  • Investigate if Junction pocket does indeed receive additional
  • verflow over the stopbanks due to the speed at which the

flows come down from the upper catchments Ongoing activity, encourage reporting where stopbanks

  • vertop & assess data from next 5 compatible flood events
  • To get the scheme running as originally intended
  • Clear vegetation in river channel / berm land
  • Clear willows downstream of scheme (i.e. below

Matarau Road Bridge) Not completed, money used for Jack’s Swale

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Long Term Objectives (5+ years)

  • Feasibility Study
  • Possible change in land-use
  • Increase flooding protection (e.g. higher stopbanks, larger

floodgates, sacrificial areas)

  • Hydrologists interpretation of future hydrographs

No definitive action has been taken on any of these activities as addressing short/medium term objectives. Do we want to pursue any of these or continue focusing on maintaining status quo and clearing the debt?

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AOB

  • Date of next meeting?