Cost components for bioretention practices
| Implementation Stage | Primary Cost Components | Basic Cost Estimate | Other Considerations |
|---|---|---|---|
| Site Preparation | Tree & plant protection | Protection Cost ($/area) x Affected Area | Removal of existing structures, topsoil removal and stockpiling |
| Clearing & grubbing | Clearing Cost ($/area) x Affected Area | Removal of existing structures, topsoil removal and stockpiling | |
| Topsoil salvage | Clearing Cost ($/area) x Affected Area | Removal of existing structures, topsoil removal and stockpiling | |
| Site Formation | Excavation / grading | 4-ft Depth Excavation Cost ($/acre) x Area (acre) | Soil & rock fill material, tunneling |
| Hauling material offsite | Excavation Cost x (% of Material to be hauled away) | Soil & rock fill material, tunneling | |
| Structural Components | Under-drains | Under-drain cost ($/lineal foot) x length of device | Pipes, catch-basins, manholes, valves |
| Inlet structure | ($/structure) or ($/curb cut) | Pipes, catch-basins, manholes, valves | |
| Outlet structure | ($/structure) | Pipes, catch-basins, manholes, valves | |
| Liner | Liner cost ($/square yard) x area of device) | Pipes, catch-basins, manholes, valves | |
| Site Restoration | Filter strip | Sod cost ($/square foot) x filter strip area | Tree protection, soil amendments, seed bed preparation, trails |
| Soil preparation | Topsoil or amendment cost ($/acre) x Area (acre) | Tree protection, soil amendments, seed bed preparation, trails | |
| Seeding | Seeding Cost ($/acre) x Seeded Area (acre) | Tree protection, soil amendments, seed bed preparation, trails | |
| Planting / transplanting | Planting Cost ($/acre) x Planted Area (acre) | Tree protection, soil amendments, seed bed preparation, trails | |
| Annual Operation, Maintenance, and Inspection | Debris removal | Removal Cost ($/acre) x Area (acre) x Frequency | Vegetation maintenance, cleaning of structures |
| Sediment removal | Removal Cost ($/acre) x Area (acre) x Frequency | Vegetation maintenance, cleaning of structures | |
| Weed control | Labor cost ($/hour) x Hours per visit x Frequency | Vegetation maintenance, cleaning of structures | |
| Inspection | Inspection Cost ($) x Inspection Frequency | Vegetation maintenance, cleaning of structures | |
| Mowing | Mowing Cost ($) x Mowing Frequency | Vegetation maintenance, cleaning of structures |