Diagnosing delivery capabilities on a large international nature-based solutions project

Nature-based solutions (NBS) are increasingly recognised as an effective response to a number of major urban challenges. These include heatwaves^1,2,3, flooding^4,5,6, water quality^7,8 and public health and wellbeing^9,10,11. While the concept of NBS emerged as recently as 2015¹², the idea of using urban nature to address these issues also features prominently in the more established fields of ecosystem services (which emerged in 2005)¹³ and green infrastructure (2002)¹⁴.

Despite mounting evidence of their benefits, strategies built around NBS are seldom practically realised¹⁵; implementation in cities has been slow, inconsistent and often limited to demonstration sites^{16,17,18,19,20,21}. For example, 6 years after Copenhagen embraced green infrastructure as a response to its acute flooding problems in 2011, the implementation of green infrastructure was only just ‘taking off’ in 2017, and remained highly contested²². Even retaining existing urban NBS remains a challenge; tree canopy cover, central to mitigation of urban heat island effects, is declining in many cities^23,24. For example, metropolitan Melbourne experienced a loss of 2000 hectares between 2014 and 2018²⁵. In the US, an average of 36 million trees were lost each year from urban areas between 2009 and 2014²⁶.

Barriers within the organisations responsible for implementing NBS are frequently identified as a primary reason for limited NBS delivery^{16,17,23,27,28,29}. Delivery organisations have significant path dependencies; existing regimes are self-enforcing, and change is difficult^30,31.

The reasons for non-delivery have been characterised in detail in a broad range of literature. Barriers are highlighted in studies focused on urban forestry^32,33, urban water management^18,29,34, nature-based solutions^35,36 and climate adaptation^37,38. The issue has been investigated through the lenses of mainstreaming^39,40, governance^{19,21,33,34,41,42}, transitions^{31,36,43,44,45} and general analyses of barriers^17,23,46,47. Papers describing the barriers to NBS have drawn on interviews with experts^{17,23,33,34,36,48}, and direct project experiences^49,50. At the time of writing, we are aware of nine review papers that present typologies of barriers to NBS delivery, based on systematic reviews of the considerable literature^{16,18,21,29,32,37,41,46,47}.

These studies have identified a largely consistent set of eight essential (and frequently lacking) traits for successful NBS implementation in local government. Leadership support is critical, both at the political and executive level^{18,20,21,29,34,41,51,52}. A project team with the right capacity and timeframes to implement projects is also important^{32,37,51,53,54}, as is a framework of internal mechanisms that facilitate the delivery of NBS, including clear approval processes, supportive policies and laws, and well-established standards for NBS design and maintenance^{16,18,20,35,47,55,56,57}. A positive, supportive organisational culture for delivering new projects is also necessary, recognising that new NBS projects often have inherent (and novel) risks and trade-offs^{17,19,20,32,33,47,52,58}. Finally, access to teams within the organisation that are both suitably skilled and supportive is vital^{16,18,23,46,54,59,60}. Beyond the organisation itself, it is common for other levels of government to play an important role in approving aspects of NBS projects; an absence of support or clear process from higher regulatory authorities can pose a significant barrier^{32,33,38,44,51}. Effective community engagement is also noted as important, recognising that many NBS need public support and/or private property owner consent to be successful^{23,37,38,46,49,61,62,63,64}.

While the barriers to NBS delivery have been the subject of significant attention, the implementation gap persists, with recent publications continuing to note the difficulty of NBS delivery^33,36,52,57.

A range of theoretical frameworks offer insight into how the implementation gap might be addressed. In the field of governance, The Policy Arrangement Model⁶⁵ has been used to conceptualise governance in urban forestry^32,33 and urban stormwater management^21,34 as the temporary balance of a set of actors, discourses, rules and resources; changes to these variables may lead to changes in governance.

In the Policy Arrangement Model, each of these four elements is significant, as is their interplay³³. The actors included (or excluded) in a policy arrangement are crucial, given the range of agendas in typical stakeholders (e.g. politicians, community groups, chambers of commerce, financiers etc.), as are the relations between these actors (some may operate as coalitions, or as antagonists). Discourses include tacit and explicit conceptualisations of what the policy problem is, how it should be solved, and what values matter most. These are important in lending legitimacy to rules, which define interactions and roles between actors. These may be as formal as laws and design standards, or as informal as a set of undocumented organisational processes and norms (e.g. “talk to Anne in our compliance branch, she usually decides what is safe”). These elements are all vital in determining who deploys resources such as staff time, skills, budgets or equipment, and how they are deployed. Collectively, the dynamics between these four elements constitute a policy arrangement; changes in one element have the potential to affect others, and in turn spark shifts in governance⁶⁵. However, these systems can be strongly entrenched⁶⁶. Governance shifts are theorised to be typically driven by at least four factors: policy entrepreneurs (or ‘champions’), shock events, socio-political changes and ‘adjacent arrangements’ (developments in policy domains in related sectors or institutions)⁶⁷.

Policy entrepreneurs are also a focus of mainstreaming research, which highlights how these individuals advance NBS uptake by working within organisations to involve key stakeholders, engage citizens and contract technical expertise while incrementally introducing NBS considerations into planning practice³⁵. This work is conceptualised as ‘horizontal’ mainstreaming, as officers champion NBS across their organisations, but it is argued that this must be supported by ‘vertical’ actions by top-down actors (such as executives and elected leaders) with the power to determine resource allocations and organisational structures^39,40.

To support NBS development and planning, the European Union’s Horizon 2020 programme initiated a series of large international demonstration projects, each involving collaborations between a number of cities, consultancies and universities. These include the UnaLab, ProGIreg, Connecting Nature, GrowGreen, Urban GreenUP and EdiCitNet projects⁶⁸. These projects generally fund dedicated staff, as well as on-ground delivery of NBS, and have potential to address some or all of the barriers to NBS delivery that cities face. When considered in terms of the Policy Arrangement Model, the new actors, discourses and resources introduced by these projects all challenge the ‘temporary balance’ theorised to constitute the organisational status quo⁶⁵. These projects also may encourage governance shifts⁶⁷, by both facilitating the hiring of NBS policy entrepreneurs, and increasing a city’s exposure to influential adjacent arrangements in other centres of NBS expertise, such as university research units or exemplar municipalities. With the involvement of organisational champions/policy entrepreneurs, mainstreaming activities such as stakeholder outreach, citizen engagement and intra-organisational collaboration become increasingly possible³⁵.

This paper investigates the Horizon 2020 NBS project, Urban GreenUP. Urban GreenUP focuses on supporting partner cities to prepare NBS plans, as well as funding a multi-million Euro programme of investment in NBS interventions including floating vegetated islands, green walls on private structures, and streambank renaturalisation. The seven cities participating actively as project partners are Liverpool (UK), Ludwigsburg (Germany), Mantova (Italy), Valladolid (Spain), Izmir (Turkey), Quy Nhon (Vietnam) and Medellín (Colombia). This group of cities represents a wide range of governance arrangements and urban contexts in which NBS delivery occurs; Liverpool is a significant post-industrial centre emerging from sustained economic challenges compounded by government austerity, while Mantova has large areas of UNESCO world heritage and a legacy of industrial pollution. Quy Nhon is a coastal holiday town fairly new to NBS, while Ludwigsburg has extensive environmental legislation and has already successfully carried out major streambank restoration works on their local river. The former is largely governed by provincial government, with more operational management at a local level, whereas the latter has individual portfolio mayors, including one for the city’s environment. Valladolid has a population of 300,000 and a fairly compact urban form, whereas Medellin numbers over two million residents. We were able to work with each of these cities, effectively capturing the full range of capabilities and experiences in the Urban GreenUP project, and a significant variety of landscapes and organisational contexts in which NBS may be implemented.

While the ‘generalisability’ of case studies is often limited, the constraints can be at least partially addressed through strategic sampling of cases⁶⁹. Our sample is diverse, and while limited to seven cities, it does represent the full cohort of cities participating in this major EU programme designed to promote NBS innovation. A smaller sample size allows for a close, qualitative study of each case. Urban GreenUP presents a valuable opportunity to investigate the persistence of NBS barriers within local governments with ambitions for NBS implementation, with implications both for future innovation-oriented programmes such as Horizon 2020, and potentially the broader practice of NBS delivery in cities.

Many cities beyond the Urban GreenUP group are preparing new NBS plans and programmes, and could benefit from insights arising from this study. Each GreenUP city is embarking on NBS planning and delivery and, at the time of our research, each had an individual or team employed with a specific NBS delivery role (with potential to serve the policy entrepreneur role highlighted in the literature). Local government often plays a key role in the implementation of urban NBS^39,47,70, and Urban GreenUP places these organisations at its centre. Citizen engagement is an explicit focus of the project, as is the making of plans; these are both emphasised as opportunities for mainstreaming new practices^35,71.

We analyse the NBS implementation capacity of the cities within this study using an approach generally consistent with the practice of theory-based evaluation^72,73. This ‘theory-based’ method breaks an implementation programme into its component elements, and assesses each element against available theory regarding what is required for success. This poses significant advantages over other evaluative methods because it focuses on the causative elements that lead to policy success or failure, rather than just the final outcomes achieved⁷⁴, and is therefore more conducive to reforms of the institutional barriers discussed above.

Theory-based evaluation typically takes place at the end of projects, but ours is ex ante; an approach noted by Weiss in her seminal outline of theory-based evaluation as having the potential to improve programme planning⁷². Evaluative practices have been noted as a particular weakness in local government NBS programmes, both at the political and officer level, due to a fear that acknowledging problems would lead to criticism of failures³⁶. We sought to mitigate this issue both through use of an ex ante approach, and by designing a tool that creates distance between evaluators and individual practitioners.

This paper investigates the enduring difficulties faced by cities seeking to deploy NBS, in the context of a major NBS project spanning seven cities. We had two key research questions. First, do case study cities have the capabilities required for successful NBS delivery, or are there barriers that continue to make this difficult? Second, does identifying and measuring a city’s NBS delivery capabilities facilitate improvements in these capabilities?

We elicited organisational barriers from NBS practitioners in participating cities using a purpose-built diagnostic tool. We used this approach because tools that enable organisations to learn about their success factors have the potential to address implementation gaps^44,71.

The tool was developed to bring lessons from the literature into an operational context, by enabling practitioners to assess and rate their organisation’s capability levels across eight key areas, such as political support, alignment between teams, and technical knowledge (refer to Table 1). The tool posed a series of questions pertaining to each of these eight capability areas; users answered by selecting from a set of pre-defined answers. The tool associated each answer with a level of capability, which was reported as a final assessment of an organisation’s capabilities. This was provided to the practitioner directly on completion of the tool’s questions, enabling an immediate estimate of their organisation’s NBS delivery capacity, and a diagnosis of any key barriers they would be likely to face in future NBS projects. These results formed the basis for our reflections on NBS delivery capacity within Urban GreenUP, as well as discussions with practitioners to understand how results of the tool were received.

Our research proceeded in three steps. First, we drew on the literature to define a set of eight key capabilities—which we call ‘success factors’—for NBS; these formed the basis of the tool. Second, practitioners within NBS teams in participating cities used the tool to identify their capability levels. Finally, we interviewed users to evaluate the impact of the tool.

Source: Ecology - nature.com