| Option 2 - Maintain Existing Regime | ||||||
| Cost Item | Item Description | Assumptions | Quantity | Unit | Rate | Item Cost |
| Total Existing Maintenance | £4,900 | |||||
| 1 | Relief Channel maintenance | Machine and dumper for 4 days at £300 per day with 2 Operatives at £12 per hour (7.5 hour day) and remove debris from site. | 1 | Item | 2,500 | 2,500 |
| 2 | Culvert maintenance | Machine and dumper for 4 days at £300 per day with 2 Operatives at £12 per hour (7.5 hour day). | 1 | Item | 2,400 | 2,400 |
| Annual Post Construction Maintenance Cost | 4,900 |
| Option 3a - Relief Channel Enlargement | ||||||
| Cost Item | Item Description | Assumptions | Quantity | Unit | Rate | Item Cost |
| Total Flood Storage Reservoir Cost | £470,740 | |||||
| 1 | Excavate material for widening of existing channel and preparation of surface. | Removal of 215 m3 required. Excavate and remove from site. | 215 | m3 | 12 | 2,580 |
| 2 | Excavate material for widening of existing concrete channel and preparation of surface. | Removal of 1065 m3 required. Excavate and remove from site. | 1,065 | m3 | 12 | 12,780 |
| 3 | Removal of existing reinforced concrete channel. | Removal of 241 m3 required. Excavate and remove from site. | 241 | m3 | 23 | 5,543 |
| 4 | Tipping at Licensed tip. | Tipping of excavated material to licensed tip. | 1,521 | m3 | 20 | 30,420 |
| 5 | Construction of new concrete channel. | 502 m3 of concrete required. Rate includes providing RMC and placing. | 502 | m3 | 64 | 32,128 |
| 6 | Formwork for new concrete channel. | Formwork rough finish for walls. | 2,484 | m2 | 41 | 101,844 |
| 7 | Reinforcement for new concrete channel. | Assume 1% steel from concrete volume required. 5 m3 of steel required. | 39 | tonne | 250 | 9,750 |
| 8 | Replacement of culvert. | Assume 8 m length. Replace with Precast box culvert 2400 mm x 1800 mm installed by pipe gang and plant (£75 per m). | 8 | m | 575 | 4,600 |
| 9 | Install Headwalls | Construct 2 No. headwalls to culvert. | 1 | Item | 4,000 | 4,000 |
| 8 | Localised bunding. | Assume bunding required to protect properties on Barton and Herschel Road. | 1 | Item | 20,000 | 20,000 |
| 8 | Landscaping / Reinstatement | Spread and Rotivate topsoil, reseed locations and miscellaneous. Assume 10m width at £1 per m2. | 7,400 | m2 | 1 | 7,400 |
| Construction Cost | 231,045 | |||||
| 9 | General Contingency | Allow 25% of Construction Cost | 57,761 | |||
| 10 | General and Preliminary Items | Allow 25% | 72,202 | |||
| 11 | Overhead and Profit | Allow 15% | 54,151 | |||
| Relief Channel Enlargement Capital Works Cost | 415,159 | |||||
| 12 | Relief Channel maintenance | Machine and dumper for 4 days at £300 per day with 2 Operatives at £12 per hour (7.5 hour day) and remove debris from site. | 1 | Item | 2,500 | 2,500 |
| Annual Post Construction Maintenance Cost | 2,500 | |||||
| 13 | Design | Design at 10% of Construction Cost and General contingency. | 1 | Item | 28,881 | 28,881 |
| 14 | Supervision Cost | Half time supervisor at £35 per hour for 16 weeks (18.75 hour week) and Project Manager at £40 per hour for 10 hours per week. | 1 | Item | 16,900 | 16,900 |
| 15 | Agency costs | Project Manager at £40 per hour for 1 day (7.5 hour day) per week for 16 weeks. | 1 | Item | 4,800 | 4,800 |
| 16 | Planning Supervisor Services | Allowance of £2500 (min for small scheme) | 1 | Item | 2,500 | 2,500 |
| Reservoir Design, Supervision and Agency Cost | 53,081 |
| Option 3b - Culvert Enlargement | ||||||
| Cost Item | Item Description | Assumptions | Quantity | Unit | Rate | Item Cost |
| Total Flood Storage Reservoir Cost | £609,663 | |||||
| 1 | Remove existing culvert. | Removal of 157 m required. Excavate and remove from site. Assume 3m depth to remove. | 471 | m3 | 18 | 8,478 |
| 2 | Excavate material for new culvert | Assume 3.4 m width x 3 m depth. | 1,130 | m3 | 12 | 13,560 |
| 3 | Tipping at Licensed tip. | Tipping of removed material to licensed tip. | 1,601 | m3 | 20 | 32,020 |
| 4 | Fill material. | Import fill material for box culvert base and surround 157 m length. | 415 | m3 | 14 | 5,810 |
| 5 | Construction of new culvert. | Precast box concrete culvert. Assume 2400 mm width x 1800 mm height for supply and delivery only. Installed by concrete pipe gang and plant 2.5-3.0m deep (£75 per m). | 157 | m | 575 | 90,275 |
| 6 | Construction of manholes. | Provision of 2 No. manholes. Assume precast concrete 900 mm diameter at depth 1.5 m. | 2 | Nr | 768 | 1,536 |
| 7 | Install Headwalls and weedscreen. | Construction of 2 No. headwalls and provision of weedscreen. | 1 | Item | 5,000 | 5,000 |
| 8 | Services interruption. | Depending on locations. Allow for utility company costs of £1000 per utility. Assume 4 utilities are affected. | 4 | Item | 1,000 | 4,000 |
| 9 | Working around services. | Supporting services. | 1 | Item | 10,000 | 10,000 |
| 10 | Replace footpath. | Replace footpath 100 m length 3 m width. | 300 | m2 | 8 | 2,400 |
| 11 | Replace Road. | Replace road 57 m length 6 m width. | 342 | m2 | 12 | 4,104 |
| 12 | Foul sewer. | Assume 10,000 for temporarily diverting/moving foul sewer pipe. | 1 | Item | 10,000 | 10,000 |
| Localised bunding. | Assume bunding required to protect properties on Barton and Herschel Road. | 1 | Item | 20,000 | 20,000 | |
| 13 | Boundary walls and fencing. | Replace boundary walls and fences. Assume 100 m length, fencing/walls both sides. | 200 | m | 50 | 10,000 |
| 14 | Landscaping / Reinstatement | Spread and Rotivate topsoil, reseed locations and miscellaneous. Assume 10m width at £1 per m2. | 1,570 | m2 | 1 | 1,570 |
| 15 | Difficult working. | Difficult and tight working conditions between existing housing. Assume extra construction cost. | 1 | Item | 90,275 | 90,275 |
| Construction Cost | 309,028 | |||||
| 6 | General Contingency | Allow 25% of Construction Cost | 77,257 | |||
| 7 | General and Preliminary Items | Allow 25% | 96,571 | |||
| 8 | Overhead and Profit | Allow 15% | 72,428 | |||
| Culvert Enlargement Capital Works Cost | 555,285 | |||||
| 9 | Culvert maintenance | Machine and dumper for 4 days at £300 per day with 2 Operatives at £12 per hour (7.5 hour day). | 1 | Item | 2,400 | 2,400 |
| Annual Post Construction Maintenance Cost | 2,400 | |||||
| 10 | Design | Design at 10% of Construction Cost and General contingency. | 1 | Item | 38,629 | 38,629 |
| 11 | Supervision Cost | Half time supervisor at £35 per hour for 8 weeks (18.75 hour week) and Project Manager at £40 per hour for 10 hours per week. | 1 | Item | 8,450 | 8,450 |
| 12 | Agency costs | Project Manager at £40 per hour for 1 day (7.5 hour day) per week for 8 weeks. | 1 | Item | 2,400 | 2,400 |
| 13 | Planning Supervisor Services | Allowance of £2500 (min for small scheme) | 1 | Item | 2,500 | 2,500 |
| Reservoir Design, Supervision and Agency Cost | 51,979 |
| Option 4a - Provision of Flood Storage Reservoir to 50 year standard of protection (Flood Defence Only) | ||||||
| Cost Item | Item Description | Assumptions | Quantity | Unit | Rate | Item Cost |
| Total Flood Storage Reservoir Cost | £484,369 | |||||
| 1 | Excavate lagoon and use the material to construct surrounding embankments. | 10,000m3 of storage required. Assume reservoir is outside floodplain. Excavate, Transport, Place and Compact at a rate of £10/m3. | 10,000 | m3 | 10 | 100,000 |
| 2 | Inlet and Outlet Control Structures | Assume 1 inlet and 1 outlet. All Headwalls in-situ concrete, fitted with penstock (for emergency closure or repair) and weedscreen. | 1 | Item | 50,000 | 50,000 |
| 3 | Emergency Spillway | Assume 100m length spillway with width of 3m and scour protection. | 1,000 | m2 | 20 | 20,000 |
| 4 | Construction of Culvert | Assume 40m length. Precast concrete culvert 2.4 x 2.4m | 40 | m | 1,000 | 40,000 |
| 5 | Landscaping / Reinstatement | Spread and Rotivate topsoil, reseed locations and miscellaneous. Allow 2m storage depth at £1 per m2. | 5,000 | m2 | 1 | 5,000 |
| 6 | Services interruption | Depending on locations. Allow for utility company costs of £1000 per utility. Assume 3 utilities are affected. | 3 | Item | 1,000 | 3,000 |
| Construction Cost | 218,000 | |||||
| 7 | General Contingency | Allow 25% of Construction Cost | 54,500 | |||
| 8 | General and Preliminary Items | Allow 25% | 68,125 | |||
| 9 | Overhead and Profit | Allow 15% | 51,094 | |||
| Storage Reservoir Capital Works Cost | 391,719 | |||||
| 10 | Reservoir Maintenance | Supervising Engineer at £50 per hour for 2 days ( 7.5 hour day). | 15 | hours | 50 | 750 |
| 11 | Grass cutting of reservoir and maintenance of control structures | Tractor with side arm cutter, plus one hand held strimmer for 5 days at £200 per day. Together with 2 Operatives at £12 per hour (7.5 hour day). | 1 | Item | 1,900 | 1,900 |
| Annual Post Construction Maintenance Cost | 2,650 | |||||
| 12 | Design | Design at 10% of Construction Cost and General contingency. Plus Panel engineer at £65 per hour for 2 weeks (7.5 hour day) | 1 | Item | 32,125 | 32,125 |
| 13 | Supervision Cost | Full time supervisor at £35 per hour for 24 weeks (37.5 hour week) and Project Manager at £40 per hour for 22.5 hours per week. Plus Panel Engineer at £65 per hour for 2 weeks (37.5 hour week). | 1 | Item | 45,375 | 45,375 |
| 14 | Agency costs | Project Manager at £40 per hour for 2 days (7.5 hour day) per week for 10 weeks | 1 | Item | 6,000 | 6,000 |
| 15 | Planning Supervisor Services | Allowance of £6500 | 1 | Item | 6,500 | 6,500 |
| Reservoir Design, Supervision and Agency Cost | 90,000 |
| Option 4b - Provision of Flood Storage Reservoir to 100 year standard of portection (Flood Defence Only) | ||||||
| Cost Item | Item Description | Assumptions | Quantity | Unit | Rate | Item Cost |
| Total Flood Storage Reservoir Cost | £585,267 | |||||
| 1 | Excavate lagoon and use the material to construct surrounding embankments. | 15,000m3 of storage required. Assume reservoir is outside floodplain. Excavate, Transport, Place and Compact at a rate of £10/m3. | 15,000 | m3 | 10 | 150,000 |
| 2 | Inlet and Outlet Control Structures | Assume 1 inlet and 1 outlet. All Headwalls in-situ concrete, fitted with penstock (for emergency closure or repair) and weedscreen. | 1 | Item | 50,000 | 50,000 |
| 3 | Emergency Spillway | Assume 100m length spillway with width of 3m and scour protection. | 1,000 | m2 | 20 | 20,000 |
| 4 | Construction of Culvert | Assume 40m length. Precast concrete culvert 2.4 x 2.4m | 40 | m | 1,000 | 40,000 |
| 5 | Landscaping / Reinstatement | Spread and Rotivate topsoil, reseed locations and miscellaneous. Allow 2m storage depth at £1 per m2. | 7,500 | m2 | 1 | 7,500 |
| 6 | Services interruption | Depending on locations. Allow for utility company costs of £1000 per utility. Assume 3 utilities are affected. | 3 | Item | 1,000 | 3,000 |
| Construction Cost | 270,500 | |||||
| 7 | General Contingency | Allow 25% of Construction Cost | 67,625 | |||
| 8 | General and Preliminary Items | Allow 25% | 84,531 | |||
| 9 | Overhead and Profit | Allow 15% | 63,398 | |||
| Storage Reservoir Capital Works Cost | 486,055 | |||||
| 10 | Reservoir Maintenance | Supervising Engineer at £50 per hour for 2 days ( 7.5 hour day). | 15 | hours | 50 | 750 |
| 11 | Grass cutting of reservoir and maintenance of control structures | Tractor with side arm cutter, plus one hand held strimmer for 5 days at £200 per day. Together with 2 Operatives at £12 per hour (7.5 hour day). | 1 | Item | 1,900 | 1,900 |
| Annual Post Construction Maintenance Cost | 2,650 | |||||
| 12 | Design | Design at 10% of Construction Cost and General contingency. Plus Panel engineer at £65 per hour for 2 weeks (7.5 hour day) | 1 | Item | 38,688 | 38,688 |
| 13 | Supervision Cost | Full time supervisor at £35 per hour for 24 weeks (37.5 hour week) and Project Manager at £40 per hour for 22.5 hours per week. Plus Panel Engineer at £65 per hour for 2 weeks (37.5 hour week). | 1 | Item | 45,375 | 45,375 |
| 14 | Agency costs | Project Manager at £40 per hour for 2 days (7.5 hour day) per week for 10 weeks | 1 | Item | 6,000 | 6,000 |
| 15 | Planning Supervisor Services | Allowance of £6500 | 1 | Item | 6,500 | 6,500 |
| Reservoir Design, Supervision and Agency Cost | 96,563 |
| Option 4c - Provision of Flood Storage Reservoir to 100 year standard and Wetland Area | ||||||
| Cost Item | Item Description | Assumptions | Quantity | Unit | Rate | Item Cost |
| Total Flood Storage Reservoir Cost | £1,796,048 | |||||
| 1 | Excavate lagoon and use the material to construct surrounding embankments. | 75,000m3 of storage required. Assume reservoir is outside floodplain. Excavate, Transport, Place and Compact at a rate of £10/m3. | 75,000 | m3 | 10 | 750,000 |
| 2 | Inlet and Outlet Control Structures | Assume 1 inlet and 1 outlet. All Headwalls in-situ concrete, fitted with penstock (for emergency closure or repair) and weedscreen. | 1 | Item | 50,000 | 50,000 |
| 3 | Emergency Spillway | Assume 100m length spillway with width of 3m and scour protection. | 1,000 | m2 | 20 | 20,000 |
| 4 | Construction of Culvert | Assume 40m length. Precast concrete culvert 2.4 x 2.4m | 40 | m | 1,000 | 40,000 |
| 5 | Landscaping / Reinstatement | Spread and Rotivate topsoil, reseed locations and miscellaneous. Allow 2m storage depth at £1 per m2. | 37,500 | m2 | 1 | 37,500 |
| 6 | Services interruption | Depending on locations. Allow for utility company costs of £1000 per utility. Assume 3 utilities are affected. | 3 | Item | 1,000 | 3,000 |
| Construction Cost | 900,500 | |||||
| 7 | General Contingency | Allow 25% of Construction Cost | 225,125 | |||
| 8 | General and Preliminary Items | Allow 25% | 281,406 | |||
| 9 | Overhead and Profit | Allow 15% | 211,055 | |||
| Storage Reservoir Capital Works Cost | 1,618,086 | |||||
| 10 | Reservoir Maintenance | Supervising Engineer at £50 per hour for 2 days ( 7.5 hour day). | 15 | hours | 50 | 750 |
| 11 | Grass cutting of reservoir and maintenance of control structures | Tractor with side arm cutter, plus one hand held strimmer for 5 days at £200 per day. Together with 2 Operatives at £12 per hour (7.5 hour day). | 1 | Item | 1,900 | 1,900 |
| Annual Post Construction Maintenance Cost | 2,650 | |||||
| 12 | Design | Design at 10% of Construction Cost and General contingency. Plus Panel engineer at £65 per hour for 2 weeks (7.5 hour day) | 1 | Item | 117,438 | 117,438 |
| 13 | Supervision Cost | Full time supervisor at £35 per hour for 24 weeks (37.5 hour week) and Project Manager at £40 per hour for 22.5 hours per week. Plus Panel Engineer at £65 per hour for 2 weeks (37.5 hour week). | 1 | Item | 45,375 | 45,375 |
| 14 | Agency costs | Project Manager at £40 per hour for 2 days (7.5 hour day) per week for 10 weeks | 1 | Item | 6,000 | 6,000 |
| 15 | Planning Supervisor Services | Allowance of £6500 | 1 | Item | 6,500 | 6,500 |
| Reservoir Design, Supervision and Agency Cost | 175,313 |