Characteristics of grey infrastructure and LSGI
| . | Grey infrastructure . | LSGI . |
|---|---|---|
| Financial costs | Capital costs plus operations and maintenance | Varies – may have lower capital costs, but higher operation and maintenance costs (Talberth & Hanson 2012; Talberth et al. 2012; EPA 2015) |
| Specificity of function | Can be optimized to perform specific functions well | By definition achieves multiple benefits, although potential to optimize natural processes for specific goals may vary |
| Performance | Generally effective at reaching primary goals, but often causes externalities (Iuell et al. 2003) | Relies upon integration of at least one natural process, potentially increasing variability and uncertainty in performance; integration potentially reduces externalities; performance risks could vary widely depending on operations and maintenance |
| Design life | Durable infrastructure can have design life of decades, but materials eventually fail and fall short of design functions | Different project lifespans possible, depending upon the operation and maintenance of the asset, but projects that make use of natural structures and processes can be designed to last significantly longer than grey infrastructure with appropriate maintenance, even indefinitely |
| Asset characteristics | Asset always depreciates over time | Asset may appreciate over time if maturity of biota results in better performance. |
| . | Grey infrastructure . | LSGI . |
|---|---|---|
| Financial costs | Capital costs plus operations and maintenance | Varies – may have lower capital costs, but higher operation and maintenance costs (Talberth & Hanson 2012; Talberth et al. 2012; EPA 2015) |
| Specificity of function | Can be optimized to perform specific functions well | By definition achieves multiple benefits, although potential to optimize natural processes for specific goals may vary |
| Performance | Generally effective at reaching primary goals, but often causes externalities (Iuell et al. 2003) | Relies upon integration of at least one natural process, potentially increasing variability and uncertainty in performance; integration potentially reduces externalities; performance risks could vary widely depending on operations and maintenance |
| Design life | Durable infrastructure can have design life of decades, but materials eventually fail and fall short of design functions | Different project lifespans possible, depending upon the operation and maintenance of the asset, but projects that make use of natural structures and processes can be designed to last significantly longer than grey infrastructure with appropriate maintenance, even indefinitely |
| Asset characteristics | Asset always depreciates over time | Asset may appreciate over time if maturity of biota results in better performance. |