PRELIMINARY COST ESTIMATES OF STORAGE OPTIONS IN THE HURUNUIWAIRAU ZONE

Transcription

1 PRELIMINARY COST ESTIMATES OF STORAGE OPTIONS IN THE HURUNUIWAIRAU ZONE Engineers and Geologists

2 PRELIMINARY COST ESTIMATES OF STORAGE OPTIONS IN THE HURUNUI-WAIRAU ZONE Report prepared for: Environment Canterbury Report prepared by: Mark Broughton, Civil Engineer... Report reviewed by: Paul Morgan, Christchurch Manager... Report Reference: A Date: 21 February 2011 Copies to: Environment Canterbury 1 copy Riley Consultants Ltd 1 copy Aqualinc Research Ltd 1 copy Revision: Details: Date: 0.1 Draft Report 21 February 2011

3 Contents 1.0 Introduction Background Scope Objectives Methodology Dams Pumping Electricity Generation Other Infrastructure and Costs Operational costs Storage Options Hurunui South Branch Lake Sumner HWP and NTP Options Waitohi HWP Option Waitohi Fraser Geologics Option Waitohi Direct Project Management Ltd Option Mandamus Pahau Catchment Only Option Pahau Waiau Transfer Option Pahau Pump Storage Option Countess Stream Hanmer River Waiau Transfer 240m RL Cost Estimates... 1 Appendices Appendix A: Cost Estimates Appendix B: Geology

4 PRELIMINARY COST ESTIMATES OF STORAGE OPTIONS IN THE HURUNUI-WAIRAU ZONE 1.0 Introduction 1.1 Background The Canterbury Water Management Strategy (CWMS) is a collaborative partnership between Environment Canterbury, Canterbury's district and city councils, central government and Ngai Tahu, as well as key water stakeholders. Past technical studies instigated by the CWMS have assessed potential storage options throughout the North Canterbury region for improving and increasing the supply of reliable water for irrigation. A previous report (RILEY REF: A) issued in 2010 evaluated options for providing water for irrigation from various sources and concluded that bulk storage was required to provide reliable irrigation. 1.2 Scope The purpose of this study is to provide a capital cost estimate for the construction of various storage reservoirs and associated infrastructure including an estimate of the operating costs. Aqualinc have modelled the storages to assess the area of land that can be reliably irrigated. The results of these two studies will provide an estimate of the cost per area of land to enable consideration of the economic feasibility of the different options and provide a comparison between them. A detailed breakdown of the cost estimates is included in Appendix A. A desktop review of the geology has been undertaken for each site and a summary is included in Appendix B. A number of previous studies have considered the capital costs for storage options. These studies have been undertaken by various parties and there is a large variation in the amount of work and stage of development they have been taken to. The current study has attempted to apply a consistent approach to calculating the capital and operating costs at each site. In addition, a brief desktop assessment of the surrounding geology has been undertaken for all of the storage sites, which identifies key geological hazards and evaluates the suitability of site materials for earth dam construction. The following is a list of storage reservoir sites that have been requested by the Hurunui- Waiau Zone Committee to be included in this assessment: Lake Sumner Hurunui South Branch Waitohi (Three options from Hurunui Water Project, Fraser Geologics & Direct project Management Ltd)

5 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page 2 Pahau (Three Options) Mandamus (Lower site) Waiau Transfer Hanmer River This is a desktop assessment with information being derived from known costs for recent projects. Information has also been provided by the following parties: Hurunui Water Project (HWP) Ngai Tahu Property (NTP) Meridian Energy (ME) Direct Project Management Ltd (DPML) Fraser Geologics (FG) Aqualinc Environment Canterbury (ECan) We have made use of various previous studies predominantly those undertaken for the parties mentioned above as well as other sources such as Ministry of Works and Development. Infrastructure costs for the distribution of water from the storages have not been included at this stage. In general these costs will be similar for many of the options although the following points need to be considered: Waitohi Storage options will not require pumping to the irrigation areas above 300 m RL which some of the other options may require. The distribution costs of irrigation south of the Hurunui will be different than the areas north of the river, particularly where existing infrastructure may be used. All of the intakes on the Hurunui or Waiau River will require a means to exclude fish and sediment removal. Some of the options proposed are at locations where this will be more difficult and may have a higher construction cost. It was agreed at initial meeting with ECan and other parties that for consistency we would provide a cost estimate based on earth fill dams with a maximum operating range of 25 m. Subsequently we have agreed to also consider the costs based on a Roller Compacted Concrete (RCC) dam at each site. It should be noted that none of the current options being considered have been assessed to sufficient detail that there is certainty over the best dam construction type. The 25 m range has been accepted as suitable at this stage as there is no known precedence in New Zealand for dams with a greater operating range. Our brief does not include consideration of environmental or other consent related issues which we understand are to be considered separately. 21 February 2011 Riley Consultants Ltd

6 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page Objectives To provide a capital cost estimate for the construction of various storage reservoirs and associated infrastructure including an estimate of the operating costs. To provide details of dam storage and operating levels to Aqualinc to enable them to model irrigation potential. To complete a desktop assessment of key geological issues for each of the potential reservoir sites particularly in terms of fatal flaws or major feasibility issues. 2.0 Methodology As discussed in the introduction as much as possible a standardised approach to the estimate of costs has been applied. The dam volume and reservoir storages have been assessed using the contours provided by Topo Map. The lengths of other infrastructure including roads, canals, pumping mains, tunnels and penstocks have also been based on these maps. 2.1 Dams In general there are five main aspects of the dam that contribute to the construction cost. The following is a summary of these aspects and the approach we have taken in estimating costs are as follows: 1. Dam Construction Type. The most suitable option in regards to the engineering and economics will depend on the geotechnical issues of foundation conditions, geometry, spillway, diversion during construction and dam material availability. For the purpose of providing a consistent approach to the cost estimate in this assessment we have assumed that all of the dams will be constructed as either earth fill or RCC. For earth dams we have applied an all up unit rate of $20/m 3. The geometry applied for the dam is slope batters of 2H:1V, crest width of 5 m and a freeboard above reservoir level of 5 m. This all up cost allows for the major elements of foundation preparation, placement of fill materials, internal drainage, rip rap and miscellaneous items. This unit rate is based on past experience and a recently completed project. It should be noted however there is no recent NZ precedent of dams of this height in terms of an actual tendered price. The RCC dam geometry applied is a vertical upstream face and 0.8H:1V downstream face, no top width as is assumed a roadway will be constructed as an addition to downstream side and not add any significant volume and a 3 m freeboard. For the RCC dam have applied an all up unit rate of $80/m 3. There have not been any large RCC dams constructed in New Zealand and this rate is based on some overseas examples. 2. Geotechnical Issues of Foundation and Abutments. For some sites issues may arise which require major additional expenditure such as stabilising unstable slopes and foundations, foundation treatment of permeable or very weak foundations. We have made no allowance at this stage for additional expenditure of this type as there has not been sufficient work undertaken to accurately assess this. The Clyde Dam is a very good example where major slope stability issues in the reservoir led to very significant cost. 21 February 2011 Riley Consultants Ltd

7 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page 4 3. Spillways. The spillways in some cases can be a very large component of the cost. This can be a significant issue in considering the economics of different dam types as a RCC dam has the advantage of the spillway being constructed as part of the dam. However for most of these sites they are not on major rivers, and thus spillway costs are relatively modest compared to the size of the dam The main influence on the spillway cost is the dam height and the design flow. For the design flow we have used the estimate by NIWA provided on their website for the 1% AEP flood event and multiplied this by a factor of 3 to give an indicative estimate of the probable maximum flood (PMF). The PMF is the usual maximum design flood for dams of this size. 4. Diversion during Construction. The cost of diversion is dependent on the flood flows and the geometry of the dam site. 5. Appurtenant Structures (Intake tower and outlets). For large dams with an operating range of 25 m the intake tower will be a significant structure. There are a number of ways that the intake can be designed into the dam and for this exercise we have assumed a lump sum for this item based on dam height and design outflow. For dams that have included hydro power infrastructure 2.2 Pumping Pumping is included in a number of the options including Waitohi (HWP and DPML), Mandamus and Pahau. The costs of the pump infrastructure have been based on information from a number of sources. Aqualinc have modelled the operation of pumps and potential generation flows. The assumptions and approach they have undertaken will be detailed in their report. No optimisation of pump and generation infrastructure has been undertaken in this work. There will be a balance between the capital cost, operating costs and revenue from generation to provide the most economic solution but that is beyond the scope of this current assessment. We have estimated the costs of pumping based on total energy used and used a rate of 13 c/kwh. 2.3 Electricity Generation Generation at a number of sites is likely to be marginal from an economic perspective. We have included the costs for the options with and without generation included. Estimating the capital and operating costs of generation is very complex and the approach we have taken is a very simplified one as not possible within current brief to do more than that. We have not included any costs associated with transmission we would need a lot more detail on the current network. It is likely that South Branch would have greater transmission costs than the other sites given more remote location. For the schemes that have pumping as well as storage we have assumed pump generators would be used except for Waitohi HWP Option as the pump and generation infrastructure is separate. From discussions with ME we have assumed that Pumps and Generators are the same cost and a pump generator is 1.5 times the cost. We have estimated the revenue from generation based on total energy produced and used a rate of 8 c/kwh. This does not allow for peaking revenue. The flows provided by Aqualinc are based on prioritising run of river flows and therefore are not optimised for electricity generation. 21 February 2011 Riley Consultants Ltd

8 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page Other Infrastructure and Costs This has included roads, canals, tunnels, pump mains, penstocks and river intakes. We have applied rates based on recent construction projects and information from other sources including Meridian. Reparation for land used has been determined by using a standard rate of $17,000/ha. This figure has been determined using Meridian data, but will vary depending on the location of the proposed storage. 2.5 Operational Costs This includes the costs associated with operation and maintenance of the storage components of the schemes. We have also included estimates for the costs of dam safety compliance, environmental and the intake where it is in addition to the likely run of river take on the Hurunui River. The costs for pumping and hydro electric generation are based on total energy use and production as well as a percentage of the cost of M&E equipment. Our estimates of the operational costs are very simple and based on limited information and therefore require further work to improve. 3.0 Storage Options The following is a summary of additional information for each option and includes an issues highlighted from a review of geology. Most of the options have only been developed to screening stage prior to prefeasibility in regards to the engineering with the exception of Hurunui South Branch and Lake Sumner which could be considered to be between prefeasibility and feasibility. A review of the Geology at each site is included in Appendix B Geology. This includes a summary of the key geological features and some comment on potential issues at each site. 3.1 Hurunui South Branch HWP have undertaken detailed geological mapping of the dam site and reservoir, aerial surveys, detailed 3D modelling of the dam site, flood estimation to size spillway and development of engineering concepts. The proposed dam is 75 m high and has a live storage of 111 Mm 3. This site has had the most detailed engineering assessment undertaken to date. No direct subsurface investigation has been undertaken. However as part of geotechnical investigation undertaken for HWP a significant amount of geological mapping as well as geophysical survey (Seismic and Ground Penetrating Radar) was undertaken for the dam site. This has highlighted a potential issue of seepage in the right abutment but this can not be quantified until further work including subsurface investigations is undertaken. The assessment for HWP suggested that a RCC central dam and earth fill dams on the abutments may be the best option. The cost estimate undertaken in this study has considered earth and RCC dams separately but this highlights that the optimal solution at this site and possibly others may be a combination depending on the geometry of the valley. 21 February 2011 Riley Consultants Ltd

9 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page 6 There is the potential for hydro power at the dam but may be a relatively expensive site to develop due to issues such as high transmission costs. At this stage generation has not been included in the cost estimates. 3.2 Lake Sumner HWP and NTP Options HWP have undertaken detailed geological mapping of the outlet, both aerial and terrestrial surveys and development of engineering concepts. There are some potential issues with the geology in regards to foundations but given the proposed gate structure these are not considered significant. The diversion of flows during construction is a significant issue. The geometry of Lake Outlet enables diversion around the left bank of the river. The costs for this structure have been based on the work undertaken for HWP. This has assumed a gate structure at the outlet using bottom hinged (flap) gates as these are considered most suitable for this location. We have not provided a separate cost for the NTP option as the physical difference is very minor and would not necessarily require a significant change in the gate structure. 3.3 Waitohi HWP Option HWP have undertaken aerial surveys, 3D modelling of the dam site and development of engineering concepts. This option includes an intake on the Hurunui River downstream of Surveyors Stream, a pump station to pump up 70 m, a canal and tunnel to convey water through to the Waitohi catchment. The proposed dam is located at Seven Hills and is 106 m high which provides a live storage of 100 Mm 3. This option requires pumping up approximately 70 m in elevation with potential generation from the storage m. A pumping rate of 8 m 3 /s has been used as this was provided by HWP. This pump rate has not been optimised for either irrigation demand or the potential of generation revenue. The proposed canal crosses the Esk fault. There is no obvious earth liner at the dam site and nearest source appears to be approximately 5 km away. HWP have recently had an aerial survey of the dam site and reservoir to provide 1 m contours. HWP are continuing work on this option to attempt to improve the economics. 3.4 Waitohi Fraser Geologics Option We have not been sent details of this option but we understand FG has undertaken an aerial survey and developed engineering concepts. We have assumed the same dam location and storage as outlined in DPML option (Section 3.5). The proposed dam is 97 m high and has a live storage of 104 Mm 3. This option includes a tunnel at approximately 440 m RL which is approximately 8 km long. Waitohi Downs fault is within 300 m of dam site to the east. Dam rock-fill is anticipated to be available from canal and tunnel cuts. Core material may not be available in situ. The closest appropriate material is likely to be Tertiary sediments within 3-4km of the dam sites. 3.5 Waitohi Direct Project Management Ltd Option DPML have undertaken development of engineering concepts. The proposed dam is 97 m high and has a live storage of 104 Mm February 2011 Riley Consultants Ltd

10 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page 7 Waitohi Downs fault is within 300 m of dam site to the east. Dam rock-fill is anticipated to be available from canal and tunnel cuts. Core material may not be available in situ. The closest appropriate material is likely to be Tertiary sediments within 3-4km of the dam sites. The canal alignment crosses active Waitohi Downs fault in two places including two strands of fault east of Lake Sumner Road and passes within a few tens of metres of two smaller active faults next to Hewett Road. 3.6 Mandamus HWP have considered this option as part of a desktop study undertaken in A number of different dam locations have been identified in earlier work but for this assessment the downstream option has been considered. Options of pumping into the storage to augment in catchment flows were mentioned in the 2004 report but no details provided. For this study we have assumed the configuration of pumping and Aqualinc have modelled a pump capacity based on maximum take from the river of 21.7m 3 /s. A more optimal pump rate is likely to be considerably less than that. The proposed dam is 60 m high and has a live storage of 79 Mm Pahau Catchment Only Option HWP have considered this option as part of a desktop study undertaken in The proposed dam is 55 m high and has a live storage of 21 Mm 3. No obvious fatal flaws for this option. Two active fault traces within 500 m of proposed dam site. Engineering properties of Tertiary sediments forming upper abutments of dam are likely to be highly variable; potential stability and leakage issues. It is anticipated that general embankment rock-fill will be available in situ. 3.8 Pahau Waiau Transfer Option HWP have considered this option as part of a desktop study undertaken in The proposed dam is 65 m high and has a live storage of 29 Mm 3. No obvious fatal flaws have been identified for this option. Two active fault traces occur within 500 m of the proposed dam site. The engineering properties of Tertiary sediments forming the upper abutments of dam are likely to be highly variable; there are potential stability and leakage issues. It is anticipated that general embankment rock-fill will be available in situ. 21 February 2011 Riley Consultants Ltd

11 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page Pahau Pump Storage Option The volume of the dam and reservoir storage was assessed. In comparison to other dam options considered this required a higher dam volume for a lower live storage. The dam volume for an earth dam is 5.5 Mm 3 with a live storage of 74 Mm 3. This combined with the pumping up over 200 m it was deemed not worth considering this option further. However it is important to note that feasible storages for Waiau water are very difficult to find and therefore this option may require further consideration Countess Stream The volume of the dam and reservoir storage was assessed. In comparison to other dam options considered this required a higher dam volume for a lower live storage. The dam volume for an earth dam is 6.2 Mm 3 with a live storage of 64 Mm 3. Therefore it was deemed not worth considering this option further. However it is important to note that feasible storages for Waiau water are very difficult to find and therefore this option may require further consideration Hanmer River This is one of the options mentioned in the 2009 report to ECan so has not been considered in any detail. The proposed dam is 97 m high and has a live storage of 41 Mm 3. The active Hope Fault was mapped within 2 km of proposed dam site and another unnamed fault to the east which presents moderate to major seismic hazard. Dam embankment rockfill and liner material may not available in situ. The closest likely source of silty material is 3 km away but accessing this would require construction of a bridge over the Hanmer River and associated access roads Waiau Transfer 240m RL This option provides run of river flows from the Waiau catchment. There are a number of potential different options for the configuration of this transfer. We have assumed a canal with 20 m3/s capacity from the 240 m RL contour on the Waiau River. 4.0 Cost Estimates A detailed breakdown of the cost estimates is included in Appendix A. Table 1 below summarises the cost estimate and other key indicators for the storage options. The Capital cost includes the construction of all infrastructure related to storage but does not include any of the distribution costs. We have assumed the following in estimating the costs: Preliminary and General - 10% of the construction cost. Engineering and Administration - 10% of the construction cost. Contingencies - 25% of the construction costs. 21 February 2011 Riley Consultants Ltd

12 Preliminary Economic and Geological Assessment of Potential Storage Reservoirs in the Hurunui-Wairau District RILEY Ref: A Page 9 Table 1: Summary of Costs Lake Sumner South Branch Waitohi - HWP Waitohi - FG Waitohi - DPML Pahau - Catchment Pahau Waiau pumping Waiau Transfer Mandamus Reservoir Live Storage Volume (Mm 3 ) Height (m) Hanmer Earth Dam Volume (Mm 3 ) Construction Cost ($M) Construction Cost ($M) - No Generation Height (m) RCC Dam Volume (Mm 3 ) Construction Cost ($M) Construction Cost ($M) - No Generation Operating Cost ($M/year) Operating Cost No Hydro ($M/year) Irrigation Area 23,260 47,760 44,760 46,260 50,260 15,860 52,948 47,760 40,760 39, February 2011 Riley Consultants Ltd

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14 Project Particulars Earth Dam Option Including Hydro Storage Location Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP HWP Riley Riley Riley Type Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam RL of Water Surface (m) Height of dam (m) Volume of dam (m3) 4,250,622 4,224,696 4,224,696 2,890, ,187 1,169, ,302, ,190,961 Live Storage volume (m3) 100,000, ,870, ,870,751 79,146,560 21,518,086 29,500,743 27,586, ,524, ,524,046 Storage / Dam volume Operating Range (m) Land Inundated (ha) Maximum design flow (m3/s) , Buildings Inundated Farm Access required (km) Public Road required (km) Power Lines (km) Diversion Max irrigation outflow rate (m3/s) Max diverted flow (m3/s) Length of tunnel required (km) Public roads crossed Length of channel widening (km) Length of channel required (km) Rising main (m) , Rising main head (m) Earthworks (LS) 1.0 Pumping - Generation Mean Pumping flow (m3/s) Mean Generation flow (m3/s) Pumping head (m) Generation head (m) Generation Power (MW) Generation flow rate (m3/s) Pumps (m3/s) Pump Generators (m3/s) Penstocks (m) Intake tower and outlet (LS) Unit costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam General Land Inundated d ($/ha) 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 Buildings Inundated ($/ea) 100, , , , , , , , , ,000 Farm Access required ($/km) 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 Public Road required ($/km) 136, , , , , , , , , ,000 Site Office ($/each) 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 Diversion Intake strucure costs ($/m3/s) 300, , , , , , , , , ,000 Cost of tunnel ($/km) 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 Road crossings ($/ea) 620, , , , , , , , , ,000 Cost of channel ($/km) 530, , , , , , , , ,000 Rising Main ($ea/m/8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Farm Access Crossings ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Earthworks 223,000 Pumping & Generation Pumps ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Generators ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Pump generators ($/cumec/100m) 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 Penstocks ($ea/m/ 8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Powerhouse ($/5m3/s) 800, , , , , , , , , ,000 33kV Power Lines ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Inlet structure and outlet 7,000,000 7,000,000 7,000,000 4,500,000 4,500,000 5,000,000 5,500,000 7,000,000 Earth Dam Earthworks ($/m) Spillway ($/100m & 330m3/s) 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000

15 Construction Costs Earth Dam Option Including Hydro Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam General Buildings Inundated $0 $2,500,000 $2,500,000 $1,800,000 $0 $0 $0 $0 $0 $0 Farm Access $460,000 $230,000 $230,000 $230,000 $0 $0 $0 $0 $0 $322,000 Public Road $0 $1,088,000 $1,088,000 $408,000 $0 $0 $0 $0 $0 $0 Diversion Intake $2,400,000 $6,510,000 $0 $6,510,000 $0 $1,500,000 $0 $0 $6,000,000 $0 Tunnel $15,000,000 $80,000,000 $0 $0 $0 $10,000,000 $0 $0 $0 $0 Farm Access Crossings $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Road Crossings $620,000 $0 $620,000 $0 $0 $620,000 $0 $0 $6,200,000 $0 Channel $1,325,000 $0 $561,000 $1,012,000 $0 $515,000 $0 $0 $10,800,000 $0 Rising main $4,800,000 $0 $0 $0 $0 $0 $0 $0 $0 $0 Lake Sumner Earthworks $223,000 Pumping & Generation Pumps $8,400,000 $0 $0 $0 $0 $0 $0 $0 $0 $0 Generators $39,750,000 $38,760,000 $0 $0 $7,237,500 $0 $0 $31,125,600 $0 $27,013,500 Pump Generators $0 $0 $44,672,813 $26,080,313 $0 $28,957,500 $0 $0 $0 $0 Penstock $9,460,500 $5,426, $14,771,810 $8,623, $1,013,250 $9,575,280 $0 $4,357, $0 $3,781, Powerhouse / Pump Station $5,520,000 $4,864,000 $4,484,800 $4,046,400 $1,544,000 $4,118,400 $0 $4,611,200 $0 $3,312,000 33kV Power Lines $80,000 $720,000 $640,000 $240,000 $0 $0 $240,000 $320,000 $0 $240,000 Intake structure and outlet $7,000,000 $7,000,000 $7,000,000 $4,500,000 $4,500,000 $5,000,000 $0 $5,500,000 $0 $7,000,000 Earth Dam Earthworks $85,012,000 $84,494,000 $84,494,000 $57,801,000 $14,804,000 $23,394,000 $598,000 $26,055,000 $0 $83,819,000 Spillway $6,344,495 $5,882,885 $5,882,885 $4,333,977 $3,163,939 $2,924,982 $10,350,724 $0 $4,847,099 Gates $5,475,000 Construction Cost of Scheme: $186,171,995 $237,475,285 $166,945,308 $115,585,579 $32,262,689 $86,605,162 $6,536,000 $82,320,108 $23,000,000 $130,335,489 Additional costs to scheme Preliminary and $18,617,200 $23,747,529 $16,694,531 $11,558,558 $3,226,269 $8,660,516 $653,600 $8,232,011 $2,300,000 $13,033,549 Engineering and 10% $18,617,000 $23,748,000 $16,695,000 $11,559,000 $3,226,000 $8,661,000 $654,000 $8,232,000 $2,300,000 $13,034,000 25% $46,543,000 $59,369,000 $41,736,000 $28,896,000 $8,066,000 $21,651,000 $1,634,000 $20,580,000 $5,750,000 $32,584,000 Reparation for used land $8,500,000 $9,350,000 $9,350,000 $6,800,000 $2,380,000 $2,720,000 $0 $9,350,000 $0 $3,400,000 Total scheme cost: 278,449, ,689, ,420, ,399,137 49,160, ,297,678 9,477, ,714,119 33,350, ,387,038 Storage volume per dollar ($/m3) Irrigated land (ha) 44,760 50,260 46,260 40,760 15,860 52,948 23,260 47,760 47,760 39,188 Irrigation per dollar (m2/$) Operation Costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam Operations and Maintenance Operation - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Operation - Pump/Hydro $1,203,750 $969,000 $1,116,820 $652,008 $180,938 $723,938 $0 $778,140 $0 $675,338 Maintenance - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Maintenance - Pump/Hydro $2,407,500 $1,938,000 $2,233,641 $1,304,016 $361,875 $1,447,875 $0 $1,556,280 $0 $1,350,675 Dam Safety & Environmental $500,000 $500,000 $500,000 $500,000 $500,000 $500,000 $250,000 $500,000 $250,000 $750,000 Intake $500,000 $500,000 $500,000 $500,000 $500,000 Pumping/Generation Average flow pumped up (m3/s) Average generation flow (m3/s) Head up, including rising main (m) Head down (m) After Losses: Head pumped (m) Head generation (m) Pumping (MW) - mean Generation (MW) - mean Pump power consumed (MWh/year) Generation power produced (MWh/year) Price for power consumed ($/MWh) $130 $130 $130 $130 $130 $130 $130 $130 $130 $130 Price for power generated ($/MWh) $80 $80 $80 $80 $80 $80 $80 $80 $80 $80 Cost of power consumed $3,539,390 $0 $5,343,250 $2,375,081 $0 $1,361,094 $0 $0 $0 $0 Revenue from power generated $1,524,240 $3,966,236 $1,459,416 $925,056 $230,680 $325,872 $0 $1,438,042 $0 $579,211 Annual cost of power ($) $2,015,150 -$3,966,236 $3,883,834 $1,450,025 -$230,680 $1,035,222 $0 -$1,438,042 $0 -$579,211 Annual Operation cost ($/year) $7,126,400 $440,764 $8,234,295 $4,906,049 $1,112,133 $4,707,034 $550,000 $1,896,378 $1,050,000 $2,696,801

16 Project Particulars Earth Dam Option Excluding Hydro Storage Location Waitohi - HWP Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP HWP Riley Riley Riley Type Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam RL of Water Surface (m) Height of dam (m) Volume of dam (m3) 4,250,622 4,224,696 4,224,696 2,890, ,187 1,169, ,302, ,190,961 Live Storage volume (m3) 100,000, ,870, ,870,751 79,146,560 21,518,086 29,500,743 27,586, ,524, ,524,046 Storage / Dam volume Operating Range (m) Land Inundated (ha) Maximum design flow (m3/s) , Buildings Inundated Farm Access required (km) Public Road required (km) Power Lines (km) Diversion Max irrigation outflow rate (m3/s) Max diverted flow (m3/s) Length of tunnel required (km) Public roads crossed Length of channel widening (km) Length of channel required (km) Rising main (m) , Rising main head (m) Earthworks (LS) 1.0 Pumping - Generation Mean Pumping flow (m3/s) Mean Generation flow (m3/s) Pumping head (m) Generation head (m) Generation Power (MW) Generation flow rate (m3/s) Pumps (m3/s) Pump Generators (m3/s) Penstocks (m) Intake tower and outlet (LS) Unit costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam General Land Inundated ($/ha) 17, , , , , , , , , ,000.0 Buildings Inundated ($/ea) 100, , , , , , , , , ,000 Farm Access required ($/km) 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 Public Road required ($/km) 136, , , , , , , , , ,000 Site Office ($/each) 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 Diversion Intake strucure costs ($/m3/s) 300, , , , , , , , , ,000 Cost of tunnel ($/km) 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 Road crossings ($/ea) 620, , , , , , , , , ,000 Cost of channel ($/km) 530, , , , , , , , ,000 Rising Main ($ea/m/8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Farm Access Crossings ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Earthworks 223,000 Pumping & Generation Pumps ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Generators ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Pump generators ($/cumec/100m) 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 Penstocks ($ea/m/ 8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Powerhouse 800, , , , , , , , , ,000 33kV Power Lines ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Inlet structure and outlet 7,000,000 7,000,000 7,000,000 4,500,000 4,500,000 5,000, ,500, ,000,000 Earth Dam Earthworks ($/m) Spillway ($/100m & 330m3/s) 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000 6,000,000

17 Construction Costs Earth Dam Option Excluding Hydro Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam General Buildings Inundated $0 $2,500,000 $2,500,000 $1,800,000 $0 $0 $0 $0 $0 $0 Farm Access $460,000 $230,000 $230,000 $230,000 $0 $0 $0 $0 $0 $322,000 Public Road $0 $1,088,000 $1,088,000 $408,000 $0 $0 $0 $0 $0 $0 Diversion Intake $2,400,000 $6,510,000 $6,510,000 $6,510,000 $0 $1,500,000 $0 $0 $6,000,000 $0 Tunnel $15,000,000 $80,000,000 $0 $0 $0 $10,000,000 $0 $0 $0 $0 Farm Access Crossings $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Road Crossings $620,000 $0 $620,000 $0 $0 $620,000 $0 $0 $6,200,000 $0 Channel $1,325,000 $0 $561,000 $1,012,000 $0 $515,000 $0 $0 $10,800,000 $0 Rising main $4,800,000 $0 $3,501,577 $6,510,000 $0 $17,500,000 $0 $0 $0 $0 Lake Sumner Earthworks $223,000 Pumping & Generation Pumps $8,400,000 $0 $27,667,500 $17,902,500 $0 $4,500,000 $0 $0 $0 $0 Generators $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Pump Generators $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Penstock $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Powerhouse / Pump Station $1,280,000 $0 $3,472,000 $3,472,000 $0 $800,000 $0 $0 $0 $0 33kV Power Lines $80,000 $720,000 $640,000 $240,000 $0 $0 $240,000 $320,000 $0 $240,000 Intake structure and outlet $7,000,000 $7,000,000 $7,000,000 $4,500,000 $4,500,000 $5,000,000 $0 $5,500,000 $0 $7,000,000 Earth Dam Earthworks $85,012,000 $84,494,000 $84,494,000 $57,801,000 $14,804,000 $23,394,000 $598,000 $26,055,000 $0 $83,819,000 Spillway $6,344,495 $5,882,885 $5,882,885 $4,333,977 $3,163,939 $2,924,982 $10,350,724 $0 $4,847,099 Gates $5,475,000 Construction Cost of Scheme: $132,721,495 $188,424,885 $144,166,962 $104,719,477 $22,467,939 $66,753,982 $6,536,000 $42,225,724 $23,000,000 $96,228,099 Additional costs to scheme Preliminary and $13,272,150 $18,842,489 $14,416,696 $10,471,948 $2,246,794 $6,675,398 $653,600 $4,222,572 $2,300,000 $9,622,810 Engineering and 10% $13,272,000 $18,842,000 $14,417,000 $10,472,000 $2,247,000 $6,675,000 $654,000 $4,223,000 $2,300,000 $9,623,000 25% $33,180,000 $47,106,000 $36,042,000 $26,180,000 $5,617,000 $16,688,000 $1,634,000 $10,556,000 $5,750,000 $24,057,000 Reparation for used land $8,500,000 $9,350,000 $9,350,000 $6,800,000 $2,380,000 $2,720,000 $0 $9,350,000 $0 $3,400,000 Total scheme cost: 200,945, ,565, ,392, ,643, ,958,733 99,512,380 9,477,600 70,577,297 33,350, ,930, Storage volume per dollar ($/m3) Irrigated land (ha) 44,760 50,260 46,260 40,760 15,860 52,948 23,260 47,760 47,760 39,188 Irrigation per dollar (m2/$) Operation Costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Earth Dam Weir + Gate Earth Dam N/A Earth Dam Operations and Maintenance Operation - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Operation - Pump/Hydro $210,000 $0 $691,688 $447,563 $0 $112,500 $0 $0 $0 $0 Maintenance - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Maintenance - Pump/Hydro $420,000 $0 $1,383,375 $895,125 $0 $225,000 $0 $0 $0 $0 Dam Safety & Environmental $500,000 $500,000 $500,000 $500,000 $500,000 $500,000 $250,000 $500,000 $250,000 $750,000 Intake $500,000 $500,000 $500,000 $500,000 $500,000 Pumping/Generation Average flow pumped up (m3/s) Average generation flow (m3/s) Head up, including rising main (m) Head down (m) After Losses: Head pumped (m) Head generation (m) Pumping (MW) - mean Generation (MW) - mean Pump power consumed (MWh/year) Generation power produced (MWh/year) Price for power consumed ($/MWh) $130 $130 $130 $130 $130 $130 $130 $130 $130 $130 Price for power generated ($/MWh) $80 $80 $80 $80 $80 $80 $80 $80 $80 $80 Cost of power consumed $3,539,390 $0 $5,343,250 $2,375,081 $0 $1,361,094 $0 $0 $0 $0 Revenue from power generated $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Annual cost of power ($) $3,539,390 $0 $5,343,250 $2,375,081 $0 $1,361,094 $0 $0 $0 $0 Annual Operation cost ($/year) $5,669,390 $1,500,000 $8,418,312 $5,217,769 $800,000 $3,198,594 $550,000 $1,000,000 $1,050,000 $1,250,000

18 Project Particulars RCC Dam Option Including Hydro Storage Location Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP HWP Riley Riley Riley Type RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC RL of Water Surface (m) Height of dam (m) Volume of dam (m3) 1,095, , , , , , , ,099 Live Storage volume (m3) 100,000, ,870, ,870,751 79,146,560 21,518,086 29,500,743 27,586, ,524, ,524,046 Storage / Dam volume Operating Range (m) Land Inundated (ha) Maximum design flow (m3/s) , Buildings Inundated Farm Access required (km) Public Road required (km) Power Lines (km) Diversion Max irrigation outflow rate (m3/s) Max diverted flow (m3/s) Length of tunnel required (km) Public roads crossed Length of channel widening (km) Length of channel required (km) Rising main (m) , Rising main head (m) Earthworks (LS) 1.0 Pumping - Generation Mean Pumping flow (m3/s) Mean Generation flow (m3/s) Pumping head (m) Generation head (m) Generation Power (MW) Generation flow rate (m3/s) Pumps (m3/s) Pump Generators (m3/s) Penstocks (m) Intake tower and outlet (LS) Unit costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC General Land Inundated ($/m2) 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 Buildings Inundated ($/ea) 100, , , , , , , , , ,000 Farm Access required ($/km) 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 Public Road required ($/km) 136, , , , , , , , , ,000 Site Office ($/each) 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 Diversion Intake strucure costs ($/m3/s) 300, , , , , , , , , ,000 Cost of tunnel ($/km) 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 Road crossings ($/ea) 620, , , , , , , , , ,000 Cost of channel ($/km) 530, , , , , , , , ,000 Rising Main ($ea/m/8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Farm Access Crossings ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Earthworks 223,000 Pumping & Generation Pumps ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Generators ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Pump generators ($/cumec/100m) 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 Penstocks ($ea/m/ 8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Powerhouse 800, , , , , , , , , ,000 33kV Power Lines ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Inlet structure and outlet 7,000,000 7,000,000 7,000,000 4,500,000 4,500,000 7,000,000 7,000,000 5,500,000 7,000,000 7,000,000 RCC Dam RCC ($/m)

19 Construction Costs RCC Dam Option Including Hydro Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC General Buildings Inundated $0 $2,500,000 $2,500,000 $1,800,000 $0 $0 $0 $0 $0 $0 Farm Access $460,000 $230,000 $230,000 $230,000 $0 $0 $0 $0 $0 $322,000 Public Road $0 $1,088,000 $1,088,000 $408,000 $0 $0 $0 $0 $0 $0 Diversion Intake $2,400,000 $6,510,000 $6,510,000 $6,510,000 $0 $1,500,000 $0 $0 $6,000,000 $0 Tunnel $15,000,000 $80,000,000 $0 $0 $0 $10,000,000 $0 $0 $0 $0 Farm Access Crossings $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Road Crossings $620,000 $0 $620,000 $0 $0 $620,000 $0 $0 $6,200,000 $0 Channel $1,325,000 $0 $561,000 $1,012,000 $0 $515,000 $0 $0 $10,800,000 $0 Rising main $4,800,000 $0 $0 $0 $0 $0 $0 $0 $0 $0 Lake Sumner Earthworks $223,000 Pumping & Generation Pumps $8,400,000 $0 $0 $0 $0 $0 $0 $0 $0 $0 Generators $39,750,000 $38,760,000 $0 $0 $7,237,500 $0 $0 $31,125,600 $0 $27,013,500 Pump Generators $0 $0 $44,672,813 $26,080,313 $0 $28,957,500 $0 $0 $0 $0 Penstock $9,460,500 $5,426,400 $14,771,810 $8,623,890 $1,013,250 $9,575,280 $0 $4,357,584 $0 $3,781,890 Powerhouse / Pump Station $5,520,000 $4,864,000 $4,484,800 $4,046,400 $1,544,000 $4,118,400 $0 $4,611,200 $0 $3,312,000 33kV Power Lines $80,000 $720,000 $640,000 $240,000 $0 $0 $240,000 $320,000 $0 $240,000 Intake structure and outlet $7,000,000 $7,000,000 $7,000,000 $4,500,000 $4,500,000 $7,000,000 $0 $5,500,000 $0 $7,000,000 RCC Dam RCC $109,510,000 $73,245,000 $73,245,000 $51,347,000 $13,300,000 $21,456,000 $598,000 $19,701,000 $0 $89,010,000 Spillway Gates $5,475,000 Construction Cost of Scheme: $204,325,500 $220,343,400 $156,323,423 $104,797,603 $27,594,750 $83,742,180 $6,536,000 $65,615,384 $23,000,000 $130,679,390 Additional costs to scheme Preliminary and $20,432,550 $22,034,340 $15,632,342 $10,479,760 $2,759,475 $8,374,218 $653,600 $6,561,538 $2,300,000 $13,067,939 Engineering and 10% $20,433,000 $22,034,000 $15,632,000 $10,480,000 $2,759,000 $8,374,000 $654,000 $6,562,000 $2,300,000 $13,068,000 25% $51,081,000 $55,086,000 $39,081,000 $26,199,000 $6,899,000 $20,936,000 $1,634,000 $16,404,000 $5,750,000 $32,670,000 Reparation for used land $8,500,000 $9,350,000 $9,350,000 $6,800,000 $2,380,000 $2,720,000 $0 $9,350,000 $0 $3,400,000 Total scheme cost: 304,772, ,847, ,018, ,756,363 42,392, ,146, ,477, ,492, ,350, ,885,329 Storage volume per dollar ($/m3) Irrigated land (ha) 44,760 50,260 46,260 40,760 15,860 52,948 23,260 47,760 47,760 39,188 Irrigation per dollar (m2/$) Operation Costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC Operations and Maintenance Operation - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Operation - Pump/Hydro $1,203,750 $969,000 $1,116,820 $652,008 $180,938 $723,938 $0 $778,140 $0 $675,338 Maintenance - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Maintenance - Pump/Hydro $2,407,500 $1,938,000 $2,233,641 $1,304,016 $361,875 $1,447,875 $0 $1,556,280 $0 $1,350,675 Dam Safety & Environmental $500,000 $500,000 $500,000 $500,000 $500,000 $500,000 $250,000 $500,000 $250,000 $750,000 Intake $500,000 $500,000 $500,000 $500,000 $500,000 Pumping/Generation Average flow pumped up (m3/s) Average generation flow (m3/s) Head up, including rising main (m) Head down (m) After Losses: Head pumped (m) Head generation (m) Pumping (MW) - mean Generation (MW) - mean Pump power consumed (MWh/year) Generation power produced (MWh/year) Price for power consumed ($/MWh) $130 $130 $130 $130 $130 $130 $130 $130 $130 $130 Price for power generated ($/MWh) $80 $80 $80 $80 $80 $80 $80 $80 $80 $80 Cost of power consumed $3,539,390 $0 $5,343,250 $2,375,081 $0 $1,361,094 $0 $0 $0 $0 Revenue from power generated $1,524,240 $3,966,236 $1,459,416 $925,056 $230,680 $325,872 $0 $1,438,042 $0 $579,211 Annual cost of power ($) $2,015,150 -$3,966,236 $3,883,834 $1,450,025 -$230,680 $1,035,222 $0 -$1,438,042 $0 -$579,211 Annual Operation cost ($/year) $7,126,400 $440,764 $8,234,295 $4,906,049 $1,112,133 $4,707,034 $550,000 $1,896,378 $1,050,000 $2,696,801

20 Project Particulars RCC Dam Option Excluding Hydro Storage Location Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP HWP Riley Riley Riley Type RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC RL of Water Surface (m) Height of dam (m) Volume of dam (m3) 1,095, , , , , , , ,099 Live Storage volume (m3) 100,000, ,870, ,870,751 79,146,560 21,518,086 29,500,743 27,586, ,524, ,524,046 Storage / Dam volume Operating Range (m) Land Inundated (ha) Maximum design flow (m3/s) , Buildings Inundated Farm Access required (km) Public Road required (km) Power Lines (km) Diversion Max irrigation outflow rate (m3/s) Max diverted flow (m3/s) Length of tunnel required (km) Public roads crossed Length of channel widening (km) Length of channel required (km) Rising main (m) , Rising main head (m) Earthworks (LS) 1.0 Pumping - Generation Mean Pumping flow (m3/s) Mean Generation flow (m3/s) Pumping head (m) Generation head (m) Generation Power (MW) Generation flow rate (m3/s) Pumps (m3/s) Pump Generators (m3/s) Penstocks (m) Intake tower and outlet (LS) Unit costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC General Land Inundated ($/ha) 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 17,000 Buildings Inundated ($/ea) 100, , , , , , , , , ,000 Farm Access required ($/km) 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 23,000 Public Road required ($/km) 136, , , , , , , , , ,000 Site Office ($/each) 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 90,000 Diversion Intake strucure costs ($/m3/s) 300, , , , , , , , , ,000 Cost of tunnel ($/km) 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 10,000,000 Road crossings ($/ea) 620, , , , , , , , , ,000 Cost of channel ($/km) 530, , , , , , , , ,000 Rising Main ($ea/m/8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Farm Access Crossings ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Earthworks 223,000 Pumping & Generation Pumps ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Generators ($/cumec/100m) 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Pump generators ($/cumec/100m) 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 1,875,000 Penstocks ($ea/m/ 8cumecs) 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 8,000 Powerhouse 800, , , , , , , , , ,000 33kV Power Lines ($/km) 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 80,000 Inlet structure and outlet 7,000,000 7,000,000 7,000,000 4,500,000 4,500,000 7,000,000 7,000,000 5,500,000 7,000,000 7,000,000 RCC Dam RCC ($/m)

21 Construction Costs RCC Dam Option Excluding Hydro Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC General Buildings Inundated $0 $2,500,000 $2,500,000 $1,800,000 $0 $0 $0 $0 $0 $0 Farm Access $460,000 $230,000 $230,000 $230,000 $0 $0 $0 $0 $0 $322,000 Public Road $0 $1,088,000 $1,088,000 $408,000 $0 $0 $0 $0 $0 $0 Diversion Intake $2,400,000 $6,510,000 $0 $6,510,000 $0 $1,500,000 $0 $0 $6,000,000 $0 Tunnel $15,000,000 $80,000,000 $0 $0 $0 $10,000,000 $0 $0 $0 $0 Farm Access Crossings $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Road Crossings $620,000 $0 $620,000 $0 $0 $620,000 $0 $0 $6,200,000 $0 Channel $1,325,000 $0 $561,000 $1,012,000 $0 $515,000 $0 $0 $10,800,000 $0 Rising main $4,800,000 $0 $3,501,577 $6,510,000 $0 $17,500,000 $0 $0 $0 $0 Lake Sumner Earthworks $223,000 Pumping & Generation Pumps $8,400,000 $0 $27,667,500 $17,902,500 $0 $4,500,000 $0 $0 $0 $0 Generators $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Pump Generators $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Penstock $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Powerhouse / Pump Station $1,280,000 $0 $3,472,000 $3,472,000 $0 $800,000 $0 $0 $0 $0 33kV Power Lines $80,000 $720,000 $640,000 $240,000 $0 $0 $240,000 $320,000 $0 $240,000 Intake structure and outlet $7,000,000 $7,000,000 $7,000,000 $4,500,000 $4,500,000 $7,000,000 $0 $5,500,000 $0 $7,000,000 RCC Dam RCC $109,510,000 $73,245,000 $73,245,000 $51,347,000 $13,300,000 $21,456,000 $598,000 $19,701,000 $0 $89,010,000 Spillway Gates $5,475,000 Construction Cost of Scheme: $150,875,000 $171,293,000 $120,525,077 $93,931,500 $17,800,000 $63,891,000 $6,536,000 $25,521,000 $23,000,000 $96,572,000 Additional costs to scheme Preliminary and $15,087,500 $17,129,300 $12,052,508 $9,393,150 $1,780,000 $6,389,100 $653,600 $2,552,100 $2,300,000 $9,657,200 Engineering and 10% $15,088,000 $17,129,000 $12,053,000 $9,393,000 $1,780,000 $6,389,000 $654,000 $2,552,000 $2,300,000 $9,657,000 25% $37,719,000 $42,823,000 $30,131,000 $23,483,000 $4,450,000 $15,973,000 $1,634,000 $6,380,000 $5,750,000 $24,143,000 Reparation for used land $8,500,000 $9,350,000 $9,350,000 $6,800,000 $2,380,000 $2,720,000 $0 $9,350,000 $0 $3,400,000 Total scheme cost: 227,269, ,724, ,111, ,000,650 28,190, ,362,100 9,477,600 46,355,100 33,350, ,429, Storage volume per dollar ($/m3) Irrigated land (ha) 44,760 50,260 46,260 40,760 15,860 52,948 23,260 47,760 47,760 39,188 Irrigation per dollar (m2/$) Operation Costs Storage Location: Waitohi - 7Hills Waitohi - Low Waitohi - Low Mandamus Pahau - Lower ahau - Mouse Po Lake Sumner South Branch Waiau Transfer Hanmer River HWP Fraser- Geo John Rice HWP HWP Meridian Riley Riley Riley Riley Type: RCC RCC RCC RCC RCC RCC Weir + Gate RCC N/A RCC Operations and Maintenance Operation - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Operation - Pump/Hydro $210,000 $0 $691,688 $447,563 $0 $112,500 $0 $0 $0 $0 Maintenance - General $250,000 $250,000 $250,000 $250,000 $150,000 $250,000 $150,000 $250,000 $150,000 $250,000 Maintenance - Pump/Hydro $420,000 $0 $1,383,375 $895,125 $0 $225,000 $0 $0 $0 $0 Dam Safety & Environmental $500,000 $500,000 $500,000 $500,000 $500,000 $500,000 $250,000 $500,000 $250,000 $750,000 Intake $500,000 $500,000 $500,000 $500,000 $500,000 Pumping/Generation Average flow pumped up (m3/s) Average generation flow (m3/s) Head up, including rising main (m) Head down (m) After Losses: Head pumped (m) Head generation (m) Pumping (MW) - mean Generation (MW) - mean Pump power consumed (MWh/year) Generation power produced (MWh/year) Price for power consumed ($/MWh) $130 $130 $130 $130 $130 $130 $130 $130 $130 $130 Price for power generated ($/MWh) $80 $80 $80 $80 $80 $80 $80 $80 $80 $80 Cost of power consumed $3,539,390 $0 $5,343,250 $2,375,081 $0 $1,361,094 $0 $0 $0 $0 Revenue from power generated $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Annual cost of power ($) $3,539,390 $0 $5,343,250 $2,375,081 $0 $1,361,094 $0 $0 $0 $0 Annual Operation cost ($/year) $5,669,390 $1,500,000 $8,418,312 $5,217,769 $800,000 $3,198,594 $550,000 $1,000,000 $1,050,000 $1,250,000

22