Flood Protection: Highlighting an Investment Trap Between Built and Natural Capital

Abstract

We present a simulation model developed to communicate a potential investment trap associated with using man-made river engineering to protect built infrastructure. A small system dynamics model in STELLA TM was constructed following a collaborative model-building process to increase understanding among stakeholders of the role natural capital plays in wealth creation. We set out to explore the dynamic relationship between investing tax revenue in natural capital (specifically forested headwaters and low land wetlands) rather than built capital (specifically stopbanks) for flood protection in the Manawatū watershed, New Zealand. Significant investment is currently required to maintain and enhance river engineering infrastructure and keep pace with changes in the river's geomorphology. Viewed from a systems perspective, we suggest diversion of a proportion of existing funding into restoration of forested headwaters on steep slopes and restoration of functioning wetlands on floodplains could in the longer term provide an effective approach to flood protection. Co-benefits of increased natural capital include the ecosystem services nutrient cycling, sediment capture, water purification, biodiversity, pollination, and cultural and recreational values. Overcoming an investment trap requires a longer term perspective. This simple model consisting of two feedback loops and two delays aims to contribute to an ongoing stakeholder dialogue concerning the Manawatū River watershed in New Zealand.(KEY TERMS: flood protection; natural capital; built capital; reforestation; wetland restoration; investment trap; ecosystem services.) van den Belt, Marjan, Thomas Bowen, Kimberley Slee, and Vicky Forgie, 2013. Flood Protection: Highlighting an Investment Trap Between Built and Natural Capital.

A review on trade-off analysis of ecosystem services for sustainable land-use management

“…Regarding the natural processes, there exist a great deal of uncertainties associated with large time lags in the feedback between changes in ecosystem process and other factors, posing much more difficulties in forecasting eventual outcomes and identifying the critical thresholds of ecosystem services (Holling, 1973;Rockström et al, 2009). For a balanced feedback loop during the resources management, the ability to recognize the trade-offs between current and future desirable states and 'time preferences' for ecosystem services becomes important and critical to make better decisions on land-use management (van den Belt et al, 2013).…”

A “Power and Influence” political archetype: the dynamics of public support

“…The background material for the workshop included examples of collaborative modelling, small models, and information related to ecological issues 3 3 3 3 3 3 3 3 3 3 3 3 2 2 2 2 2 2 2 2 2 (Chambers and Ghildyal, 1985;Costanza et al, 1997;Costanza, 2000;Bueno, 2012;van den Belt et al, 2013avan den Belt et al, , 2013cHill et al, 2015). The informal preworkshop email discussions included comments that influenced the aspirations of participants; for example:…”

“…Creating a library of political archetypes would add to the forward-looking, positive use of systems archetypes (Lane and Stuart, 1996;Richardson, 1997;van den Belt et al, 2013b). Among other things, it would allow a new range of critical factors to be included as endogenous variables in larger models.…”

“…As a consequence, various forms of participatory model building (e.g. Vennix, 1996;van den Belt, 2004;Hovmand, 2014) have been developed to include decision makers in the model-building process. However, to our knowledge, there has been little work undertaken by the SD community on modelling the dynamics of how power changes between communities of interest due to the influence of public support.…”

“…Politics (i.e. the art and science of governing), whether exemplified by political parties overtly or behind the scenes of modelling projects, is implicit in system dynamics models and this needs to be explicitly recognised and acknowledged (van den Belt et al, 2013a).…”