hughdenden dams concept layouts & high level cost
TRANSCRIPT
ARQ Australia (Pty) Ltd Unit 3A, 8 Corbusier Place, Balcatta, 6021, Perth WA
T: +61 8 9240 6388 I E: [email protected] I W: www.arq-au.com.au Alan Parrock1 I Thomas O’Brien2I Christopher O’Brien3
ABN 54 169 252 322 1South Africa I 2South Africa I 3Australian
Our reference: 8475/17171 R1 8 April 2019
Engeny Level 7 500 Queen St Brisbane Queensland 4000
For the attention of Mr. Andrew Vitale
Dear Sir
HUGHDENDEN DAMS – CONCEPT LAYOUTS & HIGH LEVEL COST ESTIMATES
1. TERMS OF REFERENCE
1.1. BACKGROUND
Following certain preliminary work into possible dam sites for an irrigation project to the north of Hughenden in Queensland, the Hughenden Irrigation Project Corporation (HIPCo) appointed Engeny to confirm the optimal storage arrangements in terms of dam yield. As part of this exercise the anticipated infrastructure configurations will be evaluated by trading off infrastructure requirements against incremental changes to the system yield. To this end, high-level (low accuracy) cost estimates for a number of different dam storage levels is required. Further steps in the development of the project include a preliminary geotechnical investigation to establish the basic geological/geotechnical context of the project, and a detailed lidar survey.
At this stage of the project, the anticipated configuration of the scheme includes a large dam on Betts Gorge Creek (Alstonvale Dam) and a smaller storage on Canterbury Creek (Canterbury Creek Dam) to facilitate the diversion of stream flows from external catchments into Alstonvale Dam (via a combination of gravity and pumped diversions).
In mid-March 2019, Engeny appointed ARQ Australia to develop the high-level cost estimates.
1.2. SCOPE
The scope of the high-level cost estimates is limited to the development of cost estimates for three different dam configurations:
• Alstonvale Dam (300, 500 and 700 GL storage capacity) and • Canterbury Creek Dam (100, 200 and 300 GL storage capacity).
Page | 2
The required deliverables are concept layout sketches of dams, cost estimates for different dam options, estimated accuracy of cost estimates, and list of key assumptions/qualifiers for the cost estimates.
Engeny supplied preliminary estimates of the 1:10 000 year AEP floods for use in estimating the flood handling capacity of the dams. Full Supply Levels for each storage capacity were also provided by Engeny.
2. METHODOLOGY
2.1. DAM ALIGNMENTS
The dam alignments as provided by Engeny for Alstonvale Dam and Canterbury Creek Dam are presented in Figure 1 and Figure 2 respectively. Both the geology and topography at the potential dam sites were considered and these alignments were considered the most optimal for this study.
Figure 1: Dam Alignment and basin for Alstonvale Dam. (Largest Storage Volume)
Page | 3
Figure 2: Dam Alignment and basin for Canterbury Creek Dam. (Largest Storage Volume)
2.2. PRELIMINARY GEOTECHNICAL CONSIDERATIONS
A high-level geotechnical evaluation was undertaken by newman Engineering to contextualise the geotechnical parameters of the project. While investigations are ongoing, the following discussion describes preliminary findings of the study, provided as a background to the high-level costing exercise:
2.2.1. REGIONAL GEOLOGY
1:250,000 scale Hughenden geological map shows the Alstonvale site to comprise Cenozoic Age Olivine Basalts overlying Lower Cretaceous Age Siltstone and Mudstone of the Rolling Downs Group. The Basalt effectively forms a cap (from a few metres to a maximum of 30m) over the siltstone and mudstone. Valley sides are typically covered in basalt scree or Colluvium and the valley floors contain Quaternary Age sands and gravels.
The Canterbury Creek Dam site has a similar geological profile with the only difference being the presence of mudstone rather than siltstone. Both rocks are part of the Rolling Downs Group.
The mudstones and siltstones are expected to be at least 50 metres thickness at both dam sites.
Outcrop of the mudstone or siltstone is limited in the region however there is an outcrop of mudstone approximately 20m high on the Flinders River. The outcrop is approximately 30km Northeast of Hughenden within the Mudstone unit as occur at the Canterbury Dam site. The outcrop is shown in Figure 3.
Page | 4
Figure 3: Mudstone outcrop.
The mudstone profile in Figure 3 seems consistent throughout the region. All mudstone to depth, with layers of extremely closed spaced jointing alternating with wider spacings as can be seen in Figure 3. There is a surficial weathered layer in this outcrop although the same depth of weathering was not seen near the Alstonvale site (refer testpits below). The weathered layer was approximately 5 metres thick and formed a soil material (clayey gravel) and contained gypsum layers. The presence of gypsum is common in the upper weathered mudstone. Figure 4 shows the length of the outcrop and the consistency in the various layers.
At the outcrop in Figure 3 there is a very gentle synclinal structure over the few hundred metres of the outcrop. Occasional vertical joints were noted and have been infilled. They are spaced about 4-5 per 100 metres or so of outcrop length. They appear to be stress relief joints due to anticlinal folding. A photo is Figure 5.
Page | 5
Figure 4: Outcrop length.
Figure 5: Vertical joints/fractures in Mudstone.
Page | 6
Up to 3 joint sets are present. One is near horizontal bedding joints and two others at 30 and 45 degree dip. No major failures were seen in the outcrop. No major faults, shears or other structures were noted. None were seen in the helicopter fly over or on Geo maps either.
The amount of basalt scree slopes is limited in the area of the dam sites with the basalts generally being only a few metres thick as a cap. The mudstone outcrops nearly at surface for most of the dam axis. The mudstone is highly erodible under water action. In addition, the amount of alluvium is limited in the Alstonvale site valley. Up to a few metres thick in the central 50m of the valley and comprising a silty fine sand. The Flinders river has reasonable deposits of fine to medium sand, predominantly quartz that are potentially of use in aggregate or possibly a fine filter in and embankment dam.
2.2.2. TESTPITS
Two testpits were excavated with a 20 tonne excavator approximately 200m downstream of the likely Alstonvale dam axis. Figure 6 shows the second testpit which is approximately 100m north of the creek. Figure 7 shows the excavated siltstone spoil. The first testpit was at the creek as shown in Figure 8.
Figure 6: Testpit 2.
Page | 7
Figure 7: Testpit 2 spoil.
Figure 8: Testpit 1.
Page | 8
The testpit logs are:
Testpit 1
0-3m: Alluvium. Loose silty sand, moist.
3-5.5m: Siltstone. Friable, moderately weathered. Extremely closely spaced jointing (Thinly Laminated). Excavates as a fine to coarse gravel. Low strength rock. Grading less fractured with depth. End of machine reach.
Testpit 2
0-1m: Siltstone. Friable, moderately weathered. Extremely closely spaced jointing (Thinly Laminated). Excavates as a fine to coarse gravel. Low strength rock.
1-5.5m. Siltstone. Very closely spaced joints. Slightly weathered to fresh. Grading less fractured with depth. The siltstone excavates as coarse gravel to cobbles with iron staining on joints. Intact rock is low to medium strength. Machine refused at 5.5m.
No major structures such as faults, shears are discernible just the closely spaced jointing. The 20 tonne excavator could not excavate beyond 5.5m due to resistance in Testpit 2. A ripper on the excavator would be required to progress further. The siltstone would deteriorate on exposure and repeated wet/dry cycles and working. This is also the experience of local earthwork contractors. Hence in any excavation the mudstone would need protection to prevent deterioration. The erodibility and deterioration of the mudstone at the Canterbury site would likely be more problematic than the siltstone.
No groundwater was encountered even through the alluvium in Testpit 1. Excavations at site are anticipated to be largely dry.
2.2.3. BASALT BORROW
Three grades of basalt were identified in the region of the dams:
1. Very Strong, blue/black basalt. Minimal vesicules, fresh. Occasional outcrops appear related to greater thicknesses of basalt (likely valley infill).
2. Strong blue/black basalt with vesicules and occasional calcite lining. Most common in the area.
3. Friable MW/SW basalt forms a white/grey rock. Unsuitable for concrete however locally used for screenings and roads.
The basalt caps in the vicinity of the dams is relatively thin and generally of poorer quality, predominantly Type 2 in the list above. Local quarry operators are confident of finding Type 1 basalt within 3km of the dam sites. This likely will be from an old river infill flow with 6 to 10 metre face. This should be confirmed in the next phase of investigations. Quarrying the Type 2 will be problematic for soil and timber contamination and multiple handling. This material will likely require a more complex RCC testing regime and mix design.
2.2.4. FURTHER GEOTECHNICAL STUDIES
This was a preliminary geological appraisal of the two proposed dam sites. If the project proceeds as part of the next feasibility stage geological investigations to at least confirm the following should be undertaken:
1. Suitable borrow sources for RCC and concrete production, filters, earth and rock fill borrow. 2. Detailed assessment of the likely foundation conditions for both dams. 3. The geological conditions at any proposed spillways or other key structures.
Page | 9
This would allow optimisation of the preliminary high level dam designs and further cost refinement. The geological investigations should be undertaken after the proposed Lidar has been obtained and the dam sites and other key structures confirmed.
2.3. DAM CONFIGURATIONS
2.3.1. GENERAL
While the purpose of this study is to obtain a high level comparison of dam costs for various impoundment volumes, a comprehensive dam type selection study will ultimately still be required. This is likely to follow once the initial geotechnical and topographical studies have been completed. Accordingly, for the purposes of this study, a single dam type for each dam was considered. The proposed dam configurations were estimated on the basis of experience and desktop evaluations of hydrology, geology, topography and the required storage volumes. They represent the best estimate of dam configuration at this level of study and refinement and optimisation us anticipated to follow during further phases of the project.
Appendix A includes sketches of these concept level dam configurations, conceptualised for the largest storage volume options only.
2.3.2. ALSTONVALE DAM
Considering the narrowing in the topography at the proposed alignment of Alstonvale Dam, an RCC gravity dam with a 300 m wide uncontrolled ogee spillway and stilling basin is proposed at this level of study.
The assumptions pertaining to the development of this dam configuration are listed below:
• The founding depth for a “hard” type dam was estimated to be approximately 5 m below natural ground level. It was accepted that the siltstone at this level will be suitable for the construction of an RCC dam. Cut back slopes of 1V:1.5H from the excavation level to the natural ground level were envisaged.
• Accepting suitable foundation strength at this level, a gravity dam configuration of a vertical upstream slope and downstream slope of 1V:0.75H is anticipated to be stable under the various loading conditions.
• The 1:10 000 AEP peak inflow of 4 000 m3/s was used to size the spillway. Considering the large flood to be accommodated and the relatively erodible rock at the site, it is considered necessary to spread out the flow and reduce flow concentrations as much as practical. With a 300 m wide spillway, the consequent flow concentration is 13.3 m3/s which is fairly low. This will consequently reduce the erodibility potential of the rock downstream of the spillway.
• The flood rise under the1:10 000 AEP will accordingly be some 3.5m. A total freeboard of 4m was provided to accommodate all freeboard requirements of wave action under lower recurrence flood events.
• As a result of the flat plain downstream of the dam, a basic tailwater analysis indicated the tailwater to be relatively high, in the order of RL 391.2, or roughly 6.2 m above natural ground level. This high tailwater will also serve to reduce the erodibility potential of the rock.
• While energy will be dissipated on the spillway steps, the residual energy will be dissipated in a stilling basin located downstream of the dam toe. Accommodating the high velocities at the toe of the dam, a type II USBR stilling basin with an approximate length of 32 m will be provided with a cut off toe to suitable depth.
• A downstream spillway channel will be excavated from the stilling basin founding level at a 1V:20H slope to the natural ground level. Side slopes of 1V:1.5H were anticipated to be suitable for cut slopes through the overburden.
• The spillway sidewalls will extent into stilling basin retaining walls. These walls will form the stilling basin sides, with the height controlled by the ground level.
Page | 10
• Foundation drainage and curtain grouting will be provided from a drainage gallery to improve foundation impermeability. The proposed drainage gallery will be horizontal (approximate elevation of RL 287.00 m) at the spillway section and follow the foundation up to Full Supply Level (FSL) on the flanks.
• The grout curtain orientation will be determined once information is available on the joint sets orientation at the dam site. Accepting a generally sub-horizontal geology, with possible sub-vertical secondary jointing, a grout curtain orientation of 10° towards the upstream and 30° to the abutments were used for this evaluation. The grout curtain depth has been accepted to extend to 66% of the full supply water depth. The associated foundation drainage will extend to 50% of the water depth.
• An intake structure located on the left bank will accommodate two 1.2 m diameter steel pipes extending through the dam to an outlet house located immediately downstream of the dam toe. To allow for suitable water quality extraction, seven offtake levels will be provided. Each will have an isolating butterfly valves located in a dry well, which will include suitable trash racks and fine screens upstream of the valves. Butterfly valves and sleeve valves with hoods will be provided in the downstream outlet house for reservoir draw down.
2.3.3. CANTERBURY CREEK DAM
The proposed Canterbury Creek Dam will cut across a wide plain to the south of Alstonvale dam. The valley shape is not as efficient as that of Alstonvale and the dam will, at the largest storage capacity, will be some 5.8km long. Together with a fairly low wall height the topography is indicative of an embankment type structure. To accommodate the anticipated availability of suitable construction materials, a clay cored rockfill embankments has been considered for the purposes of this study. This will be combined with a concrete gravity spillway structure in the river section.
The assumptions pertaining to the development of this dam configuration are listed below:
• Some 3m of loose overburden material will be stripped off the full footprint extent to found the rockfill on a suitable horizon not subject to possible liquefaction and consolidation.
• The clay core will be taken a further 3m down to an anticipated hard mudstone horizon to effect a cut-off.
• Accepting a pervious foundation below this level, the cut-off will be augmented with a grout curtain to approximately 66% of the full supply water depth.
• While the topography lends itself to the provision of a channel type spillway on the left flank, the erodibility of the mudstone and the length of such a return channel make this an unattractive option at this level of study. A concrete ogee structure located on the original creek alignment has accordingly been accepted as appropriate for the high-level costing study.
• At 100m wide, the spillway structure was sized to accommodate the 1:10 000 AEP peak inflow of 800 m3/s and will be configured as a concrete gravity structure. The spillway structure will be bounded on either side by tongue walls, around which the clay core and rockfill embankment shells will wrap.
• Similar to Alstonvale Dam, a wide spillway structure has been selected to maximise energy dissipation and minimise erosion potential in the return river.
• The rise in water level under extreme flood conditions will be approximately 2.5m for this length of spillway, providing a flow concentration of 8 m3/s/m. A total freeboard of 3.5m will be provided to accommodate conventional freeboard requirements for surge, seich, wave action, etc on the embankment structure under normal operational conditions.
• A bottom outlet with two 1.2 m diameter pipes will be located at the right tongue wall immediately next to the spillway. Trash racks, screens and bulkhead gates will be accommodated in a small intake tower. Butterfly valves and sleeve valves with hoods will be provided in the downstream outlet house for reservoir draw down
Page | 11
• An earthfill embankment will substitute the rockfill on the far-left bank where the embankment height decreases below 5 m. This embankment will be configured as a zoned clay core embankment dam with drains and suitable rip rap on the upstream side.
3. COST SUMMARY
3.1. COSTING MODEL
This reconnaissance study was conducted as a preliminary examination of the dam site area to obtain and evaluate existing information from which initial layouts and configurations of the dams and appurtenant structures could be made.
The cost model has been standardised with one page of items measuring the direct cost items, the Preliminary and General items and items for design, supervision and contingencies. These cost estimates are based on limited detail at the reconnaissance stage, and the cost models have thus been reduced to a few items embracing other activities. It is intended that all-in rates shall be used for measurement and cost estimation for all items.
A simple spreadsheet model, comprising a bill of rates for the first pass pricing are provided in Appendix B. The rates are based on resource costing principles provided by John Green & Associates Civil Engineers Pty. Ltd., and take into account the extent of work envisaged under each item.
3.2. RATES
In compiling the cost estimates number of assumptions had to be made due to the limited information available. These included:
• The remoteness of the site, being approximately 200 km from the coast and the city of Townsville, which in itself is not a major hub, has been considered in the build up of rates. The associated cost of materials, fuel and transport has accordingly been estimated with this as background.
• All earthworks lead distances were assumed to be 1 km, whether for spoiling or ‘borrowing’ • Soil densities were assumed so that swell and/or shrinkage factors could be established. • Rock characteristics were assumed including rippability and powder factors. • High level estimating spreadsheets were used for compiling the bulk of the estimate • The RCC/concrete price and a few other estimated costs were adopted from other
comparable projects, including recent work on Burdekin Dam.
For each dam there are a number of key items following the direct cost total in which various assumptions have been made:
• Allowance for river diversion: $5 million for Alstonvale and $2 million for Canterbury Creek Dam
• Miscellaneous items: 10% of direct cost. • Preliminaries, general and contractor profit 40% of direct cost. • Accommodation camp for entire project: $13 million. • Contingencies: 10% of direct cost and preliminaries. • Planning and design: 10% of direct cost and preliminaries. • Land acquisition: $5 million • Infrastructure costs: $2.5 million. • No taxes have been included in the cost estimate at this stage (including GST). Tax
requirements should be considered further in the next stages of the project.
3.3. COSTING SUMMARY
The estimated costs in Australian dollars, excluding taxes, are as follows:
Page | 12
Table 1 Alstonvale Dam site costs
Crest Elevation (EL m)
Storage Capacity
(GL)
Estimated Direct Cost (AUD)
Unit cost (AUD/GL)
314 300 $ 283,300,000 $ 944,333
320 500 $ 326,200,000 $ 652,400
325 700 $ 360,950,000 $ 566,142
Table2 Canterbury Creek Dam site costs
Crest Elevation (EL m)
Storage Capacity
(GL)
Estimated Direct Cost (AUD)
Unit cost (AUD/GL)
308 100 $ 184,300,000 $ 1,843,000
311.5 200 $ 238,700,000 $ 1,193,500
314 300 $ 278,400,000 $ 928,000
4. DISCUSSION
The first pass pricing exercise undertaken as discussed above provides an indication of possible project costs as a comparison between dams of different sizes only. The costing is expected to be within some 30-40% of final costs and, other than comparative, cannot be considered definitive.
It highlights that the unit storage rates for the largest size dams are the lowest in the case of both dams. Yield calculations will accordingly be required to optimise the dam sizing further. In this regard the Canterbury Creek dam is expected to be fairly inefficient as a result of the anticipated large reservoir surface area and anticipated extended lengths of embankments structures, as indicated by the relative unit costs above.
Following confirmation of the required storage volumes, detailed survey and geotechnical investigations, a suitable dam type selection study should form the next stage in project development.
Yours faithfully
David Cameron-Ellis Stephen Newman B.Eng (Hons) Pr.Eng RPEQ, MIEAUST For ARQ Australia (Pty) Ltd For Newman Engineering (Pty) Ltd
APPENDIX A CONCEPT LEVEL DAM
CONFIGURATIONS
APPENDIX B HIGH LEVEL BOQ’S
ALSTONVALE DAM EL 314
No. Pay Ref. Description Unit Quantity Rate Amount
1 Site and basin clearing
(a) Sparse ha 1.40 2 607 3 650
(b) Brush ha 0.50 2 310 1 155
(c) Trees ha 1.20 12 258 14 710
2 River Diversion Sum 1 5 000 000 5 000 000
3 Materials
(a) Clay materials for infilling at NOC ends m³ 890 15 13 050
4 Excavation
(a) Bulk
(i) All materials
- Dam footprint m³ 259 500 7 1 879 860
- Spillway channel m³ 673 500 7 4 877 300
(ii) Extra over for rock
- Dam footprint m³ 38 920 14 537 125
- Spillway channel m³ 101 000 10 1 025 266
(b) Confined
(i) All materials m³ 1 100 11 11 600
(ii) Extra over for rock m³ 1 100 18 19 957
(c) Final foundation preparation m² 21 300 92 1 955 603
5 Drilling and Grouting
(a) Curtain grouting m drill 5 000 83 415 800
6 Drainage
(b) Drainage from gallery m drill 3 750 121 455 000
7 RCC Dam
(a) Formwork
(i) Gang formed
- Upstream Side vertical m² 20 550 253 5 202 500
- Downstream Steps vertical m² 19 830 254 5 038 919
- Downstream Steps horizontal and crest m² 15 230 262 3 993 247
- Around outlet pipes m² 440 334 146 990
(ii) Intricate
- Spillway Sidewalls m² 315 431 135 630
(b) Concrete
(i) Mass
- Around outlet pipes m³ 680 690 469 293
(ii) Structural
- Spillway Sidewalls m³ 120 995 119 352
- Crest Capping at NOC m³ 820 750 615 216
(iii) RCC
- Left Side m³ 61 720 218 13 456 778
- Right Side m³ 56 600 222 12 543 146
- Spillway m³ 187 650 195 36 543 216
(c) Reinforcing
- Spillway sidewalls t 14 3 058 42 815
- Crest Capping at NOC t 82 3 019 247 550
(d) Dowels
- Spillway sidewalls m 380 43 16 470
- Crest Capping at NOC m 2430 43 104 579
(e) Facing (GEVR)
(i) Upstream face m² 20 550 57 1 173 815
(ii) Downstream face m² 35 060 57 2 000 248
(f) Joints
(i) Mass concrete
- One side of outlet block m² 115 670 77 085
(ii) Structural
- Through concrete capping at NOC m² 42 666 27 973
(iii) RCC (Incl water stops and joint formers)
- Left Side m² 3 080 89 272 745
- Right Side m² 3 350 85 286 179
- Spillway m² 9 040 81 735 928
Continue
ALSTONVALE DAM EL 314
No. Pay Ref. Description Unit Quantity Rate Amount
8 Spillway and stilling basin (EO Dam body)
(a) Formwork
(i) Gang formed
- Stilling basin walls m² 675 300 202 744
- Stilling basin floor m² 8 975 260 2 336 990
- Downstream retaining wall for channel m² 820 293 240 522
(ii) Intricate
- Chute blocks m² 230 298 68 550
- Dentated Sill m² 560 346 193 539
- Spillway Ogee m² 2 240 309 693 130
(b) Concrete
(i) Mass
(ii) Structural
- Stilling basin floor m³ 8 420 708 5 962 894
- Chute blocks m³ 25 1 095 27 379
- Dentated Sill m³ 200 1 095 219 032
- Spillway Ogee m³ 4 000 708 2 832 720
- Downstream retaining wall for channel m³ 700 1 095 766 612
- Cutoff wall, 3m into rock m³ 900 1 095 985 640
(c) Reinforcing
- Stilling basin floor t 842 3 020 2 543 130
- Chute blocks t 3 3 020 9 061
- Dentated Sill t 20 3 020 60 407
- Spillway Ogee t 360 3 020 1 087 322
- Downstream retaining wall for channel t 77 3 020 232 566
- Cutoff wall, 3m into rock t 90 3 020 271 831
(d) Dowels
- Stilling basin floor 8m into rock m 15 120 43 650 004
- Chute blocks into steps m 980 43 42 130
- Ogee into RCC m 2 000 43 85 980
- Downstream retaining wall for channel, 4m into rock m 1 010 43 43 420
(e) Joints incl waterstops
(i) Mass concrete
(ii) Structural
- Stilling basin floor m² 950 679 645 033
- Spillway Ogee m² 200 679 135 796
- Stilling basin walls m² 50 679 33 949
- Downstream retaining wall for channel m² 50 679 33 949
9 Intake and Outlet works
(a) Formwork
(i) Gang formed
- Intake tower Vertical m² 1 220 283 344 681
- Intake tower suspended slabs m² 228 333 75 817
- Intake tower house on crest m² 760 283 214 723
- Outlet house vertical walls inside and outside m² 1 070 283 302 307
- Outlet house horisontal roof m² 160 333 53 205
(ii) Intricate
- Intake tower rounded intake m² 175 333 58 193
(b) Concrete
(i) Mass
- Intake tower Base m³ 205 699 143 316
- Concrete around pipes d/s of dam m³ 580 699 405 478
(ii) Structural
- Intake tower walls m³ 1 155 713 823 763
- Intake tower suspended slabs m³ 70 763 53 425
- Intake tower house on crest m³ 290 713 206 831
- Outlet house m³ 1 375 713 980 664
(c) Reinforcing
- Intake tower walls t 139 3 021 419 915
- Intake tower suspended slabs t 8 3 021 24 168
- Intake tower house on crest t 35 3 021 105 734
- Outlet house t 165 3 021 498 460
Continue
ALSTONVALE DAM EL 314
No. Pay Ref. Description Unit Quantity Rate Amount
(d) Mechanical items
(i) Valves Sum 3 100 000 1 3 100 000
(i) Gates and screens Sum 1 230 000 1 1 230 000
(iii) Pipes and pipe specials Sum 3 680 000 1 3 680 000
(iv) Cranes and hoists Sum 1 030 000 1 1 030 000
(v) Structural steelwork Sum 205 000 1 205 000
SUB TOTAL 133 819 757
10 Landscaping % 1.00 0 500 000
11 Measurement allowance % 1 10 13 381 976
SUB TOTAL A 147 701 733
12 Preliminary & general % 1 40 59 080 693
13 Preliminary works
(a) Access road km 15 511 201 7 668 015
(b) Electricity to site Sum 1 200 000 200 000
(c) Construction water to site Sum 1 50 000 50 000
(d) Railhead & materials handling Sum 1 100 000 100 000
14 Accommodation Sum 1 13 125 000 13 125 000
SUB TOTAL B 227 925 441
15 Contingencies % 1 10 22 792 544
SUB TOTAL C 250 717 985
16 Planning design & supervision % 1 10 25 071 798
SUB TOTAL D 275 789 783
17 TAX % 1 0 0
18 Cost of land acquisition Sum 1 5 000 000 5 000 000
19 Infrastructure Costs Sum 1 2 500 000 2 500 000
TOTAL PROJECT COST 283 289 783
ALSTONVALE DAM EL 320
No. Pay Ref. Description Unit Quantity Rate Amount
1 Site and basin clearing
(a) Sparse ha 1.41 2589 3 650
(b) Brush ha 0.60 2483 1 490
(c) Trees ha 1.50 12267 18 400
2 River Diversion Sum 1 5000000 5 000 000
3 Materials
(a) Clay materials for infilling at NOC ends m³ 1 005 14 14 500
4 Excavation
(a) Bulk
(i) All materials
- Dam footprint m³ 294 500 7 2 133 350
- Spillway channel m³ 673 500 7 4 877 300
(ii) Extra over for rock
- Dam footprint m³ 43 750 14 603 735
- Spillway channel m³ 101 000 10 1 025 266
(b) Confined
(i) All materials m³ 1 100 11 11 600
(ii) Extra over for rock m³ 1 100 18 19 957
(c) Final foundation preparation m² 27 610 92 2 535 163
5 Drilling and Grouting
(a) Curtain grouting m drill 6 500 82 535 622
6 Drainage
(b) Drainage from gallery m drill 4 800 121 582 400
7 RCC Dam
(a) Formwork
(i) Gang formed
- Upstream Side vertical m² 25 605 248 6 351 692
- Downstream Steps vertical m² 24 880 249 6 186 885
- Downstream Steps horizontal and crest m² 19 000 255 4 850 154
- Around outlet pipes m² 450 334 150 192
(ii) Intricate
- Spillway Sidewalls m² 370 403 149 013
(b) Concrete
(i) Mass
- Around outlet pipes m³ 720 687 494 295
(ii) Structural
- Spillway Sidewalls m³ 140 948 132 674
- Crest Capping at NOC m³ 955 737 703 715
(iii) RCC
- Left Side m³ 90 705 198 17 958 940
- Right Side m³ 84 350 202 17 074 619
- Spillway m³ 247 505 181 44 764 169
(c) Reinforcing
- Spillway sidewalls t 17 3040 51 680
- Crest Capping at NOC t 96 3040 290 365
(d) Dowels
- Spillway sidewalls m 430 43 18 542
- Crest Capping at NOC m 2830 43 121 740
(e) Facing (GEVR)
(i) Upstream face m² 25 605 57 1 461 664
(ii) Downstream face m² 43 880 57 2 502 921
(f) Joints
(i) Mass concrete
- One side of outlet block m² 120 705 84 632
(ii) Structural
- Through concrete capping at NOC m² 47 650 30 541
(iii) RCC (Incl water stops and joint formers)
- Left Side m² 4 560 76 346 391
- Right Side m² 4 235 78 330 306
- Spillway m² 12 000 60 716 759
Continue
ALSTONVALE DAM EL 320
No. Pay Ref. Description Unit Quantity Rate Amount
8 Spillway and stilling basin (EO Dam body)
(a) Formwork
(i) Gang formed
- Stilling basin walls m² 675 300 202 744
- Stilling basin floor m² 8 975 260 2 336 990
- Downstream retaining wall for channel m² 820 293 240 522
(ii) Intricate
- Chute blocks m² 230 298 68 550
- Dentated Sill m² 560 346 193 539
- Spillway Ogee m² 2 240 309 693 130
(b) Concrete
(i) Mass
(ii) Structural
- Stilling basin floor m³ 8 420 708 5 962 894
- Chute blocks m³ 25 1095 27 379
- Dentated Sill m³ 200 1095 219 032
- Spillway Ogee m³ 4 000 708 2 832 720
- Downstream retaining wall for channel m³ 700 1095 766 612
- Cutoff wall, 3m into rock m³ 900 1095 985 640
(c) Reinforcing
- Stilling basin floor t 842 3020 2 543 130
- Chute blocks t 3 3020 9 061
- Dentated Sill t 20 3020 60 407
- Spillway Ogee t 360 3020 1 087 322
- Downstream retaining wall for channel t 77 3020 232 566
- Cutoff wall, 3m into rock t 90 3020 271 831
(d) Dowels
- Stilling basin floor 8m into rock m 15 120 43 650 004
- Chute blocks into steps m 980 43 42 130
- Ogee into RCC m 2 000 43 85 980
- Downstream retaining wall for channel, 4m into rock m 1 010 43 43 420
(e) Joints incl waterstops
(i) Mass concrete
(ii) Structural
- Stilling basin floor m² 950 679 645 031
- Spillway Ogee m² 200 679 135 796
- Stilling basin walls m² 50 679 33 949
- Downstream retaining wall for channel m² 50 679 33 949
9 Intake and Outlet works
(a) Formwork
(i) Gang formed
- Intake tower Vertical m² 1 420 279 396 667
- Intake tower suspended slabs m² 285 329 93 862
- Intake tower house on crest m² 760 279 212 298
- Outlet house vertical walls inside and outside m² 1 070 279 298 894
- Outlet house horisontal roof m² 160 329 52 694
(ii) Intricate
- Intake tower rounded intake m² 200 329 65 868
(b) Concrete
(i) Mass
- Intake tower Base m³ 205 699 143 316
- Concrete around pipes d/s of dam m³ 580 699 405 478
(ii) Structural
- Intake tower walls m³ 1 345 708 952 335
- Intake tower suspended slabs m³ 88 758 66 709
- Intake tower house on crest m³ 290 708 205 337
- Outlet house m³ 1 375 708 973 583
(c) Reinforcing
- Intake tower walls t 161 3020 486 235
- Intake tower suspended slabs t 11 3020 33 221
- Intake tower house on crest t 35 3020 105 703
- Outlet house t 165 3020 498 315
Continue
ALSTONVALE DAM EL 320
No. Pay Ref. Description Unit Quantity Rate Amount
(d) Mechanical items
(i) Valves Sum 3 115 000 1 3 115 000
(i) Gates and screens Sum 1 240 000 1 1 240 000
(iii) Pipes and pipe specials Sum 3 690 000 1 3 690 000
(iv) Cranes and hoists Sum 1 040 000 1 1 040 000
(v) Structural steelwork Sum 210 000 1 210 000
SUB TOTAL 156 824 165
10 Landscaping % 1 0 500 000
11 Measurement allowance % 1 10 15 682 416
SUB TOTAL A 173 006 581
12 Preliminary & general % 1 40 69 202 633
13 Preliminary works
(a) Access road km 15 511201 7 668 015
(b) Electricity to site Sum 1 200000 200 000
(c) Construction water to site Sum 1 50000 50 000
(d) Railhead & materials handling Sum 1 100000 100 000
14 Accommodation Sum 1 13125000 13 125 000
SUB TOTAL B 263 352 229
15 Contingencies % 1 10 26 335 223
SUB TOTAL C 289 687 452
16 Planning design & supervision % 1 10 28 968 745
SUB TOTAL D 318 656 197
17 TAX % 1 0 0
18 Cost of land acquisition Sum 1 5000000 5 000 000
19 Infrastructure Costs Sum 1 2500000 2 500 000
TOTAL PROJECT COST 326 156 197
ALSTONVALE DAM EL 325
No. Pay Ref. Description Unit Quantity Rate Amount
1 Site and basin clearing
(a) Sparse ha 1.72 2512 4 320
(b) Brush ha 0.70 2607 1 825
(c) Trees ha 1.60 11997 19 195
2 River Diversion Sum 1 5000000 5 000 000
3 Materials
(a) Clay materials for infilling at NOC ends m³ 1 400 15 20 300
4 Excavation
(a) Bulk
(i) All materials
- Dam footprint m³ 330 200 7 2 391 750
- Spillway channel m³ 673 500 7 4 877 300
(ii) Extra over for rock
- Dam footprint m³ 49 550 14 683 675
- Spillway channel m³ 101 000 10 1 025 266
(b) Confined
(i) All materials m³ 1 100 11 11 600
(ii) Extra over for rock m³ 1 100 18 19 957
(c) Final foundation preparation m² 30 820 92 2 829 622
5 Drilling and Grouting
(a) Curtain grouting m drill 8 510 83 706 526
6 Drainage
(b) Drainage from gallery m drill 6 400 121 776 750
7 RCC Dam
(a) Formwork
(i) Gang formed
- Upstream Side vertical m² 30 180 245 7 391 681
- Downstream Steps vertical m² 29 460 245 7 227 875
- Downstream Steps horizontal and crest m² 22 695 251 5 690 237
- Around outlet pipes m² 455 334 152 001
(ii) Intricate
- Spillway Sidewalls m² 420 384 161 394
(b) Concrete
(i) Mass
- Around outlet pipes m³ 760 684 519 877
(ii) Structural
- Spillway Sidewalls m³ 160 916 146 576
- Crest Capping at NOC m³ 1 130 724 817 914
(iii) RCC
- Left Side m³ 120 750 184 22 181 359
- Right Side m³ 113 850 185 21 008 009
- Spillway m³ 290 550 172 50 053 733
(c) Reinforcing
- Spillway sidewalls t 19 3024 57 455
- Crest Capping at NOC t 113 3026 341 910
(d) Dowels
- Spillway sidewalls m 490 43 21 144
- Crest Capping at NOC m 3350 43 144 040
(e) Facing (GEVR)
(i) Upstream face m² 30 180 57 1 722 252
(ii) Downstream face m² 52 155 57 2 974 294
(f) Joints
(i) Mass concrete
- One side of outlet block m² 125 697 87 183
(ii) Structural
- Through concrete capping at NOC m² 55 722 39 691
(iii) RCC (Incl water stops and joint formers)
- Left Side m² 6 030 70 419 555
- Right Side m² 5 200 73 378 289
- Spillway m² 13 750 58 803 839
Continue
ALSTONVALE DAM EL 325
No. Pay Ref. Description Unit Quantity Rate Amount
8 Spillway and stilling basin (EO Dam body)
(a) Formwork
(i) Gang formed
- Stilling basin walls m² 675 300 202 744
- Stilling basin floor m² 8 975 260 2 336 990
- Downstream retaining wall for channel m² 820 293 240 522
(ii) Intricate
- Chute blocks m² 230 298 68 550
- Dentated Sill m² 560 346 193 539
- Spillway Ogee m² 2 240 309 693 130
(b) Concrete
(i) Mass
(ii) Structural
- Stilling basin floor m³ 8 420 708 5 962 894
- Chute blocks m³ 25 1095 27 379
- Dentated Sill m³ 200 1095 219 032
- Spillway Ogee m³ 4 000 783 3 131 280
- Downstream retaining wall for channel m³ 700 783 547 974
- Cutoff wall, 3m into rock m³ 900 783 704 538
(c) Reinforcing
- Stilling basin floor t 842 3020 2 543 130
- Chute blocks t 3 3020 9 061
- Dentated Sill t 20 3020 60 407
- Spillway Ogee t 360 3020 1 087 322
- Downstream retaining wall for channel t 77 3020 232 566
- Cutoff wall, 3m into rock t 90 3020 271 831
(d) Dowels
- Stilling basin floor 8m into rock m 15 120 43 650 004
- Chute blocks into steps m 980 43 42 130
- Ogee into RCC m 2 000 43 85 980
- Downstream retaining wall for channel, 4m into rock m 1 010 43 43 420
(e) Joints incl waterstops
(i) Mass concrete
(ii) Structural
- Stilling basin floor m² 950 686 651 890
- Spillway Ogee m² 200 686 137 240
- Stilling basin walls m² 50 686 34 310
- Downstream retaining wall for channel m² 50 686 34 310
9 Intake and Outlet works
(a) Formwork
(i) Gang formed
- Intake tower Vertical m² 1 600 277 443 588
- Intake tower suspended slabs m² 342 327 111 916
- Intake tower house on crest m² 760 277 210 702
- Outlet house vertical walls inside and outside m² 1 070 277 296 647
- Outlet house horisontal roof m² 160 327 52 358
(ii) Intricate
- Intake tower rounded intake m² 225 327 73 629
(b) Concrete
(i) Mass
- Intake tower Base m³ 205 699 143 316
- Concrete around pipes d/s of dam m³ 580 699 405 478
(ii) Structural
- Intake tower walls m³ 1 500 705 1 057 334
- Intake tower suspended slabs m³ 105 755 79 263
- Intake tower house on crest m³ 290 705 204 418
- Outlet house m³ 1 375 705 969 224
(c) Reinforcing
- Intake tower walls t 180 3021 543 690
- Intake tower suspended slabs t 13 3021 39 267
- Intake tower house on crest t 35 3021 105 718
- Outlet house t 165 3021 498 383
Continue
ALSTONVALE DAM EL 325
No. Pay Ref. Description Unit Quantity Rate Amount
(d) Mechanical items
(i) Valves Sum 3 125 000 1 3 125 000
(i) Gates and screens Sum 1 250 000 1 1 250 000
(iii) Pipes and pipe specials Sum 3 700 000 1 3 700 000
(iv) Cranes and hoists Sum 1 050 000 1 1 050 000
(v) Structural steelwork Sum 215 000 1 215 000
SUB TOTAL 175 495 497
10 Landscaping % 1.00 0 500 000
11 Measurement allowance % 1 10 17 549 550
SUB TOTAL A 193 545 046
12 Preliminary & general % 1 40 77 418 018
13 Preliminary works
(a) Access road km 15 511201 7 668 015
(b) Electricity to site Sum 1 200000 200 000
(c) Construction water to site Sum 1 50000 50 000
(d) Railhead & materials handling Sum 1 100000 100 000
14 Accommodation Sum 1 13125000 13 125 000
SUB TOTAL B 292 106 080
15 Contingencies % 1 10 29 210 608
SUB TOTAL C 321 316 688
16 Planning design & supervision % 1 10 32 131 669
SUB TOTAL D 353 448 356
17 TAX % 1 0 0
18 Cost of land acquisition Sum 1 5000000 5 000 000
19 Infrastructure Costs Sum 1 2500000 2 500 000
TOTAL PROJECT COST 360 948 356
CANTERBURY CREEK DAM EL 308
No. Pay Ref. Description Unit Quantity Rate Amount
1 Site and basin clearing
(a) Sparse ha 11 2500 27 500
(b) Brush ha 11 2500 27 500
(c) Trees ha 14 12000 168 000
2 River Diversion Sum 1 2000000 2 000 000
3 Excavation
(a) Bulk
(i) All materials m³ 825 000 7 5 973 000
(ii) Extra over for rock m³ 41 250 10 418 688
(b) Confined
(i) All materials
- Spillway Cut-off wall m³ 225 11 2 374
- Clay core cutoff m³ 285 225 14 3 993 150
(ii) Extra over for rock m³ 285 450 14 3 996 300
(c) Final foundation preparation at RCC structure m² 5 450 55 299 750
4 Preparation of solum
(a) All materials m² 196 110 55 10 786 050
(b) Extra over for rock m² 22 753 35 796 355
5 Drilling and Grouting
(a) Curtain grouting m drill 8 580 82 706 992
6 Embankment
(a) Earthfill
(i) Clay for clay core rockfill m³ 355 160 15 5 327 400
(ii) Clay for earthfill m³ 6 750 13 87 750
(iii) Earthfill for earth embankment m³ 11 650 9 104 850
(b) Rockfill m³ 861 400 18 15 505 200
(c) Filters
(i) Coarse Filter material - Upstream in rockfill m³ 56 000 55 3 080 000
(ii) Fine Filter material - Upstream in rockfill m³ 56 000 56 3 136 000
(iii) Coarse Filter material - Downstream in rockfill m³ 52 280 55 2 875 400
(iv) Fine Filter material - Downstream in rockfill m³ 52 280 56 2 927 680
(v) Fine Filter material - Downstream in earthfill m³ 3 570 56 199 920
(iv) Coarse Filter material - Transition layer at rip rap m³ 410 55 22 550
(d) Rip-rap at earth embankment m³ 2 050 35 71 750
(e) Overhaul beyond 5km m³/km
(f) Extra over for toe drain m 5 000 30 150 000
7 RCC Dam
(a) Formwork
(i) Gang formed
- Upstream Side sloped m² 3 380 300 1 014 000
- Downstream Steps vertical m² 2 600 300 780 000
- Downstream Steps horizontal and crest m² 1 685 310 522 350
- Around outlet pipes m² 40 280 11 200
(ii) Intricate
- Spillway Sidewalls m² 155 950 147 250
(b) Concrete
(i) Mass
- Around outlet pipes m³ 215 699 150 285
(ii) Structural
- Spillway Sidewalls m³ 80 708 56 640
- Crest Capping at NOC m³ 145 708 102 660
(iii) RCC
- Left Side m³ 6 900 225 1 552 500
- Right Side m³ 6 900 225 1 552 500
- Spillway m³ 17 400 210 3 654 000
(c) Reinforcing
- Spillway sidewalls t 8 1095 8 760
- Crest Capping at NOC t 15 1095 15 878
(d) Dowels
- Spillway sidewalls m 130 43 5 590
- Crest Capping at NOC m 430 43 18 490
Continue
CANTERBURY CREEK DAM EL 308
No. Pay Ref. Description Unit Quantity Rate Amount
(e) Facing (GEVR)
(i) Upstream face m² 3 380 57 192 660
(ii) Downstream face m² 4 285 57 244 245
(f) Joints
(i) Mass concrete
- One side of outlet block m² 20 705 14 100
(ii) Structural
- Through concrete capping at NOC m² 15 650 9 750
(iii) RCC (Incl water stops and joint formers)
- Left Side m² 210 90 18 900
- Right Side m² 210 90 18 900
- Spillway m² 175 90 15 750
8 Spillway and stilling basin (EO Dam body)
(a) Formwork
(i) Gang formed
- Stilling basin walls m² 290 300 87 000
- Stilling basin floor m² 2 400 260 624 000
(ii) Intricate
- Chute blocks m² 50 345 17 250
- Dentated Sill m² 105 345 36 225
- Spillway Ogee m² 735 345 253 575
(b) Concrete
(i) Mass
(ii) Structural
- Stilling basin floor m³ 2 175 708 1 540 292
- Chute blocks m³ 5 1095 5 476
- Dentated Sill m³ 20 1095 21 903
- Spillway Ogee m³ 1 350 1095 1 478 466
- Cutoff wall, 3m into rock m³ 225 1095 246 411
- Stilling basin walls m³ 570 1095 624 241
(c) Reinforcing
- Stilling basin floor t 239 3020 722 616
- Chute blocks t 1 3020 1 661
- Dentated Sill t 2 3020 6 645
- Spillway Ogee t 135 3020 407 746
- Cutoff wall, 3m into rock t 25 3020 74 753
- Stilling basin walls t 63 3020 189 375
(d) Dowels
- Stilling basin floor 8m into rock m 5 600 43 240 744
- Chute blocks into steps m 330 43 14 187
- Ogee into RCC m 400 43 17 196
(e) Joints incl waterstops
(i) Mass concrete
(ii) Structural
- Stilling basin floor m² 440 679 298 751
- Spillway Ogee m² 120 679 81 478
- Stilling basin walls m² 45 679 30 554
9 Intake and Outlet works
(a) Formwork
(i) Gang formed
- Intake tower Vertical m² 760 279 212 298
- Outlet house vertical walls inside and outside m² 950 279 265 373
- Outlet house horisontal roof m² 165 329 54 341
(ii) Intricate
- Intake tower rounded intake m² 43 329 14 162
(b) Concrete
(i) Mass
- Intake tower Base m³ 140 699 97 874
- Concrete around pipes d/s of dam m³ 580 699 405 478
(ii) Structural
- Intake tower walls m³ 215 708 152 233
- Outlet house m³ 1 375 708 973 583
(c) Reinforcing
- Intake tower walls t 26 3020 77 918
- Outlet house t 165 3020 498 315
Continue
CANTERBURY CREEK DAM EL 308
No. Pay Ref. Description Unit Quantity Rate Amount
(d) Mechanical items
(i) Valves Sum 620 000 1 620 000
(i) Gates and screens Sum 1 230 000 1 1 230 000
(iii) Pipes and pipe specials Sum 736 000 1 736 000
(iv) Cranes and hoists Sum 800 000 1 800 000
(v) Structural steelwork Sum 20 500 1 20 500
SUB TOTAL 85 969 186
10 Landscaping % 1.00 1 500 000
11 Measurement allowance % 1 10 8 596 919
SUB TOTAL A 95 066 104
12 Preliminary & general % 1 40 38 026 442
13 Preliminary works
(a) Access road km 15 511201 7 668 015
(b) Electricity to site Sum 1 200000 200 000
(c) Construction water to site Sum 1 50000 50 000
(d) Railhead & materials handling Sum 1 100000 100 000
14 Accommodation Sum 1 5000000 5 000 000
SUB TOTAL B 146 110 561
15 Contingencies % 1 10 14 611 056
SUB TOTAL C 160 721 617
16 Planning design & supervision % 1 10 16 072 162
SUB TOTAL D 176 793 779
17 TAX % 1 0 0
18 Cost of land acquisition Sum 1 5000000 5 000 000
19 Infrastructure Costs Sum 1 2500000 2 500 000
TOTAL PROJECT COST 184 293 779
CANTERBURY CREEK DAM EL 311.5
No. Pay Ref. Description Unit Quantity Rate Amount
1 Site and basin clearing
(a) Sparse ha 12 2500 30 000
(b) Brush ha 12 2500 30 000
(c) Trees ha 16 12000 192 000
2 River Diversion Sum 1 2000000 2 000 000
3 Excavation
(a) Bulk
(i) All materials m³ 1 049 700 7 7 599 828
(ii) Extra over for rock m³ 52 485 10 532 723
(b) Confined
(i) All materials
- Spillway Cut-off wall m³ 225 11 2 374
- Clay core cutoff m³ 298 260 14 4 175 640
(ii) Extra over for rock m³ 298 485 14 4 178 790
(c) Final foundation preparation at RCC structure m² 5 950 55 327 250
4 Preparation of solum
(a) All materials m² 274 360 55 15 089 800
(b) Extra over for rock m² 31 077 35 1 087 695
5 Drilling and Grouting
(a) Curtain grouting m drill 10 570 82 870 968
6 Embankment
(a) Earthfill
(i) Clay for clay core rockfill m³ 503 200 15 7 548 000
(ii) Clay for earthfill m³ 39 900 13 518 700
(iii) Earthfill for earth embankment m³ 93 150 9 838 350
(b) Rockfill m³ 1 395 500 18 25 119 000
(c) Filters
(i) Coarse Filter material - Upstream in rockfill m³ 80 100 55 4 405 500
(ii) Fine Filter material - Upstream in rockfill m³ 80 100 56 4 485 600
(iii) Coarse Filter material - Downstream in rockfill m³ 75 580 55 4 156 900
(iv) Fine Filter material - Downstream in rockfill m³ 75 580 56 4 232 480
(v) Fine Filter material - Downstream in earthfill m³ 7 800 56 436 800
(iv) Coarse Filter material - Transition layer at rip rap m³ 2 400 55 132 000
(d) Rip-rap at earth embankment m³ 12 000 35 420 000
(e) Overhaul beyond 5km m³/km
(f) Extra over for toe drain m 5 300 30 159 000
7 RCC Dam
(a) Formwork
(i) Gang formed
- Upstream Side sloped m² 4 200 300 1 260 000
- Downstream Steps vertical m² 3 240 300 972 000
- Downstream Steps horizontal and crest m² 2 110 310 654 100
- Around outlet pipes m² 48 280 13 440
(ii) Intricate
- Spillway Sidewalls m² 180 950 171 000
(b) Concrete
(i) Mass
- Around outlet pipes m³ 260 699 181 740
(ii) Structural
- Spillway Sidewalls m³ 90 708 63 720
- Crest Capping at NOC m³ 145 708 102 660
(iii) RCC
- Left Side m³ 9 200 225 2 070 000
- Right Side m³ 9 200 225 2 070 000
- Spillway m³ 23 800 210 4 998 000
(c) Reinforcing
- Spillway sidewalls t 9 1095 9 855
- Crest Capping at NOC t 15 1095 15 878
(d) Dowels
- Spillway sidewalls m 140 43 6 020
- Crest Capping at NOC m 430 43 18 490
Continue
CANTERBURY CREEK DAM EL 311.5
No. Pay Ref. Description Unit Quantity Rate Amount
(e) Facing (GEVR)
(i) Upstream face m² 4 200 57 239 400
(ii) Downstream face m² 5 350 57 304 950
(f) Joints
(i) Mass concrete
- One side of outlet block m² 24 705 16 920
(ii) Structural
- Through concrete capping at NOC m² 15 650 9 750
(iii) RCC (Incl water stops and joint formers)
- Left Side m² 280 90 25 200
- Right Side m² 280 90 25 200
- Spillway m² 240 90 21 600
8 Spillway and stilling basin (EO Dam body)
(a) Formwork
(i) Gang formed
- Stilling basin walls m² 290 300 87 000
- Stilling basin floor m² 2 400 260 624 000
(ii) Intricate
- Chute blocks m² 50 345 17 250
- Dentated Sill m² 105 345 36 225
- Spillway Ogee m² 735 345 253 575
(b) Concrete
(i) Mass
(ii) Structural
- Stilling basin floor m³ 2 175 708 1 540 292
- Chute blocks m³ 5 1095 5 476
- Dentated Sill m³ 20 1095 21 903
- Spillway Ogee m³ 1 350 1095 1 478 466
- Cutoff wall, 3m into rock m³ 225 1095 246 411
- Stilling basin walls m³ 570 1095 624 241
(c) Reinforcing
- Stilling basin floor t 239 3020 722 616
- Chute blocks t 1 3020 1 661
- Dentated Sill t 2 3020 6 645
- Spillway Ogee t 135 3020 407 746
- Cutoff wall, 3m into rock t 25 3020 74 753
- Stilling basin walls t 63 3020 189 375
(d) Dowels
- Stilling basin floor 8m into rock m 5 600 43 240 744
- Chute blocks into steps m 330 43 14 187
- Ogee into RCC m 400 43 17 196
(e) Joints incl waterstops
(i) Mass concrete
(ii) Structural
- Stilling basin floor m² 440 679 298 751
- Spillway Ogee m² 120 679 81 478
- Stilling basin walls m² 45 679 30 554
9 Intake and Outlet works
(a) Formwork
(i) Gang formed
- Intake tower Vertical m² 800 279 223 472
- Outlet house vertical walls inside and outside m² 950 279 265 373
- Outlet house horisontal roof m² 165 329 54 341
(ii) Intricate
- Intake tower rounded intake m² 50 329 16 467
(b) Concrete
(i) Mass
- Intake tower Base m³ 140 699 97 874
- Concrete around pipes d/s of dam m³ 580 699 405 478
(ii) Structural
- Intake tower walls m³ 260 708 184 096
- Outlet house m³ 1 375 708 973 583
(c) Reinforcing
- Intake tower walls t 31 3020 94 227
- Outlet house t 165 3020 498 315
Continue
CANTERBURY CREEK DAM EL 311.5
No. Pay Ref. Description Unit Quantity Rate Amount
(d) Mechanical items
(i) Valves Sum 623 000 1 623 000
(i) Gates and screens Sum 1 240 000 1 1 240 000
(iii) Pipes and pipe specials Sum 738 000 1 738 000
(iv) Cranes and hoists Sum 900 000 1 900 000
(v) Structural steelwork Sum 21 000 1 21 000
SUB TOTAL 115 175 090
10 Landscaping % 1 0 500 000
11 Measurement allowance % 1 10 11 517 509
SUB TOTAL A 127 192 599
12 Preliminary & general % 1 40 50 877 040
13 Preliminary works
(a) Access road km 15 511201 7 668 015
(b) Electricity to site Sum 1 200000 200 000
(c) Construction water to site Sum 1 50000 50 000
(d) Railhead & materials handling Sum 1 100000 100 000
14 Accommodation Sum 1 5000000 5 000 000
SUB TOTAL B 191 087 654
15 Contingencies % 1 10 19 108 765
SUB TOTAL C 210 196 419
16 Planning design & supervision % 1 10 21 019 642
SUB TOTAL D 231 216 061
17 TAX % 1 0 0
18 Cost of land acquisition Sum 1 5000000 5 000 000
19 Infrastructure Costs Sum 1 2500000 2 500 000
TOTAL PROJECT COST 238 716 061
CANTERBURY CREEK DAM EL 314
No. Pay Ref. Description Unit Quantity Rate Amount
1 Site and basin clearing
(a) Sparse ha 14 2500 35 000
(b) Brush ha 14 2500 35 000
(c) Trees ha 19 12000 222 000
2 River Diversion Sum 1 2000000 2 000 000
3 Excavation
(a) Bulk
(i) All materials m³ 1 210 385 7 8 763 187
(ii) Extra over for rock m³ 60 519 10 614 270
(b) Confined
(i) All materials
- Spillway Cut-off wall m³ 225 11 2 374
- Clay core cutoff m³ 305 300 14 4 274 200
(ii) Extra over for rock m³ 305 525 14 4 277 350
(c) Final foundation preparation at RCC structure m² 6 300 55 346 500
4 Preparation of solum
(a) All materials m² 321 350 55 17 674 250
(b) Extra over for rock m² 36 400 35 1 274 000
5 Drilling and Grouting
(a) Curtain grouting m drill 14 260 82 1 175 024
6 Embankment
(a) Earthfill
(i) Clay for clay core rockfill m³ 631 600 15 9 474 000
(ii) Clay for earthfill m³ 77 610 13 1 008 930
(iii) Earthfill for earth embankment m³ 178 000 9 1 602 000
(b) Rockfill m³ 1 880 400 18 33 847 200
(c) Filters
(i) Coarse Filter material - Upstream in rockfill m³ 82 100 55 4 515 500
(ii) Fine Filter material - Upstream in rockfill m³ 82 100 56 4 597 600
(iii) Coarse Filter material - Downstream in rockfill m³ 77 000 55 4 235 000
(iv) Fine Filter material - Downstream in rockfill m³ 77 000 56 4 312 000
(v) Fine Filter material - Downstream in earthfill m³ 19 400 56 1 086 400
(iv) Coarse Filter material - Transition layer at rip rap m³ 4 120 55 226 600
(d) Rip-rap at earth embankment m³ 19 480 35 681 800
(e) Overhaul beyond 5km m³/km
(f) Extra over for toe drain m 5 600 30 168 000
7 RCC Dam
(a) Formwork
(i) Gang formed
- Upstream Side sloped m² 4 470 300 1 341 000
- Downstream Steps vertical m² 3 675 300 1 102 500
- Downstream Steps horizontal and crest m² 2 390 310 740 900
- Around outlet pipes m² 52 280 14 560
(ii) Intricate
- Spillway Sidewalls m² 220 950 209 000
(b) Concrete
(i) Mass
- Around outlet pipes m³ 300 699 209 700
(ii) Structural
- Spillway Sidewalls m³ 110 708 77 880
- Crest Capping at NOC m³ 145 708 102 660
(iii) RCC
- Left Side m³ 13 050 225 2 936 250
- Right Side m³ 13 050 225 2 936 250
- Spillway m³ 29 000 210 6 090 000
(c) Reinforcing
- Spillway sidewalls t 11 1095 12 045
- Crest Capping at NOC t 15 1095 15 878
(d) Dowels
- Spillway sidewalls m 180 43 7 740
- Crest Capping at NOC m 430 43 18 490
Continue
CANTERBURY CREEK DAM EL 314
No. Pay Ref. Description Unit Quantity Rate Amount
(e) Facing (GEVR)
(i) Upstream face m² 4 470 57 254 790
(ii) Downstream face m² 6 065 57 345 705
(f) Joints
(i) Mass concrete
- One side of outlet block m² 26 705 18 330
(ii) Structural
- Through concrete capping at NOC m² 15 650 9 750
(iii) RCC (Incl water stops and joint formers)
- Left Side m² 330 90 29 700
- Right Side m² 330 90 29 700
- Spillway m² 290 90 26 100
8 Spillway and stilling basin (EO Dam body)
(a) Formwork
(i) Gang formed
- Stilling basin walls m² 290 300 87 000
- Stilling basin floor m² 2 400 260 624 000
(ii) Intricate
- Chute blocks m² 50 345 17 250
- Dentated Sill m² 105 345 36 225
- Spillway Ogee m² 735 345 253 575
(b) Concrete
(i) Mass
(ii) Structural
- Stilling basin floor m³ 2 175 708 1 540 292
- Chute blocks m³ 5 1095 5 476
- Dentated Sill m³ 20 1095 21 903
- Spillway Ogee m³ 1 350 1095 1 478 466
- Cutoff wall, 3m into rock m³ 225 1095 246 411
- Stilling basin walls m³ 570 1095 624 241
(c) Reinforcing
- Stilling basin floor t 239 3020 722 616
- Chute blocks t 1 3020 1 661
- Dentated Sill t 2 3020 6 645
- Spillway Ogee t 135 3020 407 746
- Cutoff wall, 3m into rock t 25 3020 74 753
- Stilling basin walls t 63 3020 189 375
(d) Dowels
- Stilling basin floor 8m into rock m 5 600 43 240 744
- Chute blocks into steps m 330 43 14 187
- Ogee into RCC m 400 43 17 196
(e) Joints incl waterstops
(i) Mass concrete
(ii) Structural
- Stilling basin floor m² 440 679 298 751
- Spillway Ogee m² 120 679 81 478
- Stilling basin walls m² 45 679 30 554
9 Intake and Outlet works
(a) Formwork
(i) Gang formed
- Intake tower Vertical m² 900 279 251 406
- Outlet house vertical walls inside and outside m² 950 279 265 373
- Outlet house horisontal roof m² 165 329 54 341
(ii) Intricate
- Intake tower rounded intake m² 55 329 18 114
(b) Concrete
(i) Mass
- Intake tower Base m³ 140 699 97 874
- Concrete around pipes d/s of dam m³ 580 699 405 478
(ii) Structural
- Intake tower walls m³ 290 708 205 337
- Outlet house m³ 1 375 708 973 583
(c) Reinforcing
- Intake tower walls t 35 3020 105 099
- Outlet house t 165 3020 498 315
Continue
CANTERBURY CREEK DAM EL 314
No. Pay Ref. Description Unit Quantity Rate Amount
(d) Mechanical items
(i) Valves Sum 625 000 1 625 000
(i) Gates and screens Sum 1 250 000 1 1 250 000
(iii) Pipes and pipe specials Sum 740 000 1 740 000
(iv) Cranes and hoists Sum 950 000 1 950 000
(v) Structural steelwork Sum 21 500 1 21 500
SUB TOTAL 136 459 078
10 Landscaping % 1 0 500 000
11 Measurement allowance % 1 10 13 645 908
SUB TOTAL A 150 604 986
12 Preliminary & general % 1 40 60 241 994
13 Preliminary works
(a) Access road km 15 511201 7 668 015
(b) Electricity to site Sum 1 200000 200 000
(c) Construction water to site Sum 1 50000 50 000
(d) Railhead & materials handling Sum 1 100000 100 000
14 Accommodation Sum 1 5000000 5 000 000
SUB TOTAL B 223 864 995
15 Contingencies % 1 10 22 386 500
SUB TOTAL C 246 251 495
16 Planning design & supervision % 1 10 24 625 149
SUB TOTAL D 270 876 644
17 TAX % 1 0 0
18 Cost of land acquisition Sum 1 5000000 5 000 000
19 Infrastructure Costs Sum 1 2500000 2 500 000
TOTAL PROJECT COST 278 376 644