A systematic scoping review of the collaborative governance of environmental and cultural flows

The norm for environmental flows deliberations in centralized governance is to use these processes as participatory modelling approaches to support more inclusive decision-making (Fig. 4). Decision support tools were more common to environmental and environmental–social flow initiatives. These approaches were employed to visualize water objectives, anticipate how uses may affect downstream communities and ecosystems, and ultimately communicate the impact of water extraction to decision-makers. Decision support tools, for example, included Bayesian networks (Xue et al. 2017), optimization models (Bryan et al. 2013), game theoretical bargaining (Xu et al. 2019), fuzzy models (Sedighkia et al. 2021), multicriteria analyses (Girardi et al. 2011; Barton et al. 2020), water evaluation and planning software (Jorda-Capdevila et al. 2016), interactive displays (Ellison et al. 2019), and other techniques. These approaches are a part of a group of multidisciplinary techniques designed to use expert knowledge and available data to weigh ecological, social, and economic factors and scenarios at the nexus of food, water, and energy conflict (Xue et al. 2017). They offer the opportunity to easily communicate ecosystem services and trade-offs of water use with stakeholders and Rights holders to help them inform and be at the negotiation table to determine water-use strategies (Lazarus et al. 2012; Barton et al. 2020; O'Sullivan et al. 2020).

Decision support tools for environmental flows consideration in water resource negotiation is underway in European countries, Canada, China, Australia, Cambodia, Ethiopia, Italy, Georgia, Papua New Guinea, New Zealand, Uganda, and the United States, among others. In the Ringarooma catchment in Australia, for example, Ellison et al. (2019) worked with the Ringarooma Water Users Group using an interactive dashboard and tables to visualize and predict stream flows and precipitation. This platform offered the Water Users Group the opportunity to comment on and negotiate changes to water allocation in real time and is described as the technical foundation for co-governance (Ellison et al. 2019). In a second example in the Aosta Valley in Italy, Vassoney et al. (2019) describe a multicriteria analysis with stakeholders to evaluate water withdrawals in the context of energy, economy, fishing, landscape, and environmental criteria. The synergies, trade-offs, and stakeholder preferences related to these criteria then informed the Valley's strategic plan (Vassoney et al. 2019). As a final example, Sheer et al. (2013) use Collaborative Modelling for Decision Support tools to work with stakeholders in the Bow River Basin, Canada to create a new operating strategy for hydropower and irrigation that sets out greater water storage, release rules, in-stream flow guidelines, and water allocation to licence holders. These cases describe a movement in centralized governance towards the use of participatory models that facilitate greater community representation in water-use strategies.

Environmental flow initiatives have been a platform to delineate a water development space ahead of developments, especially in centralized watershed governance (Fig. 4). The idea of water development space appeared to be more common through environmental flow processes than those considering cultural or environmental–social flow. King and Brown (2010, p. 135–136) suggest that development space is “the difference between current conditions in the basin and the furthest level of water-resource development found acceptable to stakeholders through consideration of the scenarios.” Environmental flows processes can be one key consideration to understand water trade-offs and preferences to inform collaborative efforts to set the maximum level of degradation to which a basin can withstand (Lazarus et al. 2012; King et al. 2014). Here, there has been effort by governments who create forums to understand the priorities of different sectors and visions of stakeholders. King and Brown (2018), for example, state:

Ahead of developments, environmental flow initiatives have been a means to form a consensus development space for watersheds by setting goals for the improvement of water quality and flows to ensure at least the minimum levels for lasting public and ecological wellbeing.

Delineating a water development space is a strategy in Australia, Canada, India, Italy, Iran, Georgia, Greece, Lesotho, Mexico, New Zealand, Pakistan, South Africa, the United States, and multinational governance in Angola, Namibia, and Botswana for the Okavango Basin and Mekong, Songkhram, and Huong basins in Cambodia, China, Laos, Myanmar, Thailand, and Vietnam (Fig. 4). This theme generally appears in strategic planning, impact assessment, and integrated water resource management. In many of these countries, there is effort to create shared visions for watersheds based on scenarios (Conallin et al. 2017) and several cases identified the maximum level of degradation a watershed can withstand or what benefits must be guaranteed. In the Okavango Basin, which is one of these cases, Angola, Namibia, Botswana, and a Global Environmental Facility funded a transboundary strategic action plan, applying the DRIFT (Downstream Response to Imposed Flow Transformations) process, to understand the “costs and benefits of water allocation to river ecosystems, social structures, and local and national economies” (King et al. 2014, p. 786). For the Poonch River in Pakistan, the state completed an environmental flow assessment as part of an impact assessment for the Gulpur Hydropower project, providing strategic guidance for habitat thresholds for Kashmir catfish, dam location and operation, and a regulated biodiversity action plan (Brown et al. 2019). In these cases, environmental flows were considered in administrative processes at a higher strategic level to facilitate broader co-designed guidance for a water development space.

Collaboration between governmental authorities, stakeholders, and Rights holders has occurred more spontaneously or opportunistically during extreme hydrologic events to allow for experimentation in the governance and management of environmental flows. This phenomenon is called event space management reflecting that there is a unique event that alters how people interact, thereby potentially altering the rules and norms of traditional management (Bark et al. 2016). This strategy was more common in papers that discussed environmental or environmental–social flows (Fig. 4). Applied to environmental flows, in extreme wet and dry years, there is a brief event window or space within which non-state decision-makers can have greater influence over water-use priorities in a dry year and over decision-making on the movement of water to different social and ecological endpoints to maximize benefits of a wet year (Bark et al. 2016; Gilvear et al. 2017). Gilvear et al. (2017) uses the expression hot moments or hotspots to describe unique moments when ecosystem and cultural services can be delivered through water allocation. These events or hot moments can act as a form of river restoration to confer ecosystem and cultural benefits (Bark et al. 2017; Kaiser et al. 2020). To enable cooperation during hydrologic extremes for the delivery of ecosystem services, authors recognize a need to build trust and legitimacy in environmental flows processes and create strong coordinated multilevel institutional relationships or multi- and bi-national agreements (O'Donnell et al. 2019).

Most papers presented instances in which useful relationships were created because of water scarcity and overallocation, but only a few papers from Australia, India, Italy, Kenya, Mexico, and the United States described how a re-organization of decision-makers can occur spontaneously during environmental water delivery, often because of flooding in wet years or the need to deliver ecosystem or cultural services (Fig. 4). In Australia's Barwon–Darling (part of the Murray–Darling) catchment, for example, Jackson (2021) describes how shared responsibility for dealing with an excess amount of water in a wet year (environmental flow event) in 2018 created a shared sense of time and space because there was greater transparency in how water use was regulated by water managers. Indigenous leaders could emphasize a wider set of social–cultural relational values of water as it was moving through the waterscape and landscape. This led to a transient experiment in decentralized governance in some parts of the watershed while emphasizing governance deficiencies in others. Jackson describes the deficiencies in flow management when water movement is “objectified, compartmentalized, and represented as apolitical” (p. 468). In Mexico and the United States’ Colorado River, flooding in 2014 led to water allocation through bi-national collaboration by many people (non-profits, government, international agencies) who were personally part of an ecosystem servicing process to provide water to areas of cultural and environmental importance (Bark et al. 2016; Kerna et al. 2017; Butler et al. 2021). In India's Ganges River, key moments for greater ecosystem and cultural service delivery have occurred during the Kumbh religious festival because of coordination between the government and supportive irrigators to reduce water for agricultural uses in upstream canals and send more water downstream (Lokgariwar et al. 2014; Gilvear et al. 2017). Authors note that successful planning of such events requires co-development of socio-hydrological monitoring and modelling. While ongoing environmental flows processes provide a long-term opportunity to build relationships and scale up those collaborations to broader watershed management, spontaneous events can be harnessed as an opportunity to quickly test new forms of decentralized governance.

Cultural flow processes have been platforms for the exchange of diverse water values and asserting of Indigenous water laws and decision-making authority (Fig. 4). Through political ecology and water justice lenses, flow processes can be an avenue to work towards power redistribution in basin planning. Political ecology is about “an integrated understanding of how environmental and political forces interact to mediate social and environmental change” (Bryant 1992, p. 12). Re-politicizing water means overtly recognizing that water (distribution, quality, and more) choices reflect and reproduce existing power dynamics (Bourblanc and Blanchon 2019; Alexandra et al. 2023). Water scarcity generally results in prioritizing municipal and industrial water use over the environment and for Indigenous Nations (Colloff and Pittock 2022; Wineland et al. 2022; Dourado et al. 2023). Indigenous water justice, explained in Robison et al. (2018, p. 841), is “water and its multi-faceted connections to Indigenous Peoples' self-determination—more precisely, to the socioeconomic, cultural, and political dimensions associated with Indigenous Peoples' exercise of the right to self-determination”. Cultural flow processes in particular are an opportunity for water governance that includes Indigenous water laws, legal pluralism, the water back agenda, and treaty agreements (Hartwig et al. 2022; Leonard et al. 2023; O'Donnell 2023a). Environmental and cultural flows deliberations can be venues for explicitly working towards power redistribution and acceptance of diverse knowledge forms in water allocation and quality choices (Hartwig et al. 2022; Moggridge et al. 2022).

Commitment to water justice to improve the governance of environmental and cultural flows is largely emerging in Commonwealth countries—Canada, Australia, and New Zealand—and to some degree in the United States and Chile through the resurgence of Indigenous water laws and governance (Fig. 4). In these jurisdictions, attention to a cultural flow through Indigenous water rights is an opportunity to “direct the formation of water policy from a starting point of Indigenous sovereignty, with Indigenous governments adequately resourced to participate equitably in environmental co-governance” (Hemming et al. 2019, p. 223). In Australia, the Murray Lower Darling Rivers Indigenous Nations and Northern Basin Aboriginal Nations created the Echuca Declaration (Murray Lower Darling Rivers Indigenous Nations, and Northern Basin Aboriginal Nations 2007) to define cultural flows and recognize and reaffirm sovereignty of their waters and lands. Since this Declaration, Australia has begun to move from simply recognizing cultural values in plans, policies, and legislation to creating co-management agreements (Robinson et al. 2015; Bischoff-Mattson and Lynch 2017; Bischoff-Mattsona et al. 2018; O'Donnell et al. 2023). Curran (2019, p. 2) remarks that in Canada the “state depoliticizes decisions about water by directing them into administrative processes like environmental assessment while Indigenous communities are repoliticizing water governance by creating evaluation processes that reflect their own legal traditions and standards.” In British Columbia, First Nations (Syilx Nation, Okanagan Nation Alliance, Yinka Dene “Uza'hné; Stellat”en First Nations, Tsleil–Waututh Nation; Stk'emlúpsemc te Secwépemc) in the Cowichan and Okanagan basins, for example, are creating their own decision-making structures based on their water laws to create community assessments, cumulative effects management plans, and environmental and cultural flows rules to assert and institutionalize their co-governance of water impacted by development projects in British Columbia (Curran 2019). New Zealand is also moving towards co-governance with environmental legislation that recognises Māori values, principles, and Te Mana o te Wai (authority over water) (Taylor et al. 2020). However, scholars suggest co-designed policy and regulations with Māori need to be created based in Nga Taonga Tuku Iho (a natural resource management framework) and Nga Puna Aroha (a water allocation framework) to protect water for the environment and people (Taylor et al. 2020; Challies et al. 2022). In these cases, there is greater appreciation of relationships to water and the intangible, subjective values therein, such as custodial responsibilities, spirituality, knowledge transmission, and creation stories (Moggridge and Thompson 2021; Woods et al. 2022). Indigenous self-determination and co-governance arrangements are emerging partially through the recognition of cultural flows embedded in water rights and decision-making authority.

Water use caps and releases appear to be considered in environmental flow initiatives and to a slightly lesser extent in cultural flows and environmental–social flow initiatives across centralized and decentralized governance (Fig. 4). Horne et al. (2017d, p. 363) describe three sub-categories that fall into this strategy: (1) “cap on consumptive water use,” (2) “license conditions for water abstractors,” and (3) “conditions on storage operators or water resource managers.” Caps on consumptive water use are a “limit on the total volume of licenses issued and (or) the extraction/abstraction of water against these licenses” (Horne et al. 2017d, p 363). License conditions for water abstractors are “conditions listed on the license of individual water users that restrict the volume and (or) timing of extractions” (Horne et al. 2017d, p 363). Lastly, conditions on storage operators or water resource managers are “conditions on a storage operator prescribing releases from storage for downstream ecological needs” (Horne et al. 2017d, p 363). These categories are generally considered as a package, alongside other legal rights, management plans, and ecological reserves (Nowlan 2012; Horne et al. 2017d).

From our synthesis, we identified water use caps and release rules in Australia, Canada, Chile, China, the European Union, New Zealand, Pakistan, South Africa, Uganda, the United Kingdom, and the United States (Fig. 4). In Australia, the Water of Act of 2007 details a sustainable diversion limit and strategic water releases by the Commonwealth Environmental Water Holder in the Murray–Darling Basin (Acreman et al. 2017). In contrast, the European Union Water Framework Directive leaves each country to define flow releases and abstraction rates, though the European Union does have the legal power to suggest an amendment to an abstraction licence (Acreman and Ferguson 2010). In the United Kingdom (formerly part of the European Union before 2020), the Thames Catchment Abstraction Management strategy calculate the maximum abstraction based on environmental flow indicators, but these indicators did not meet Water Framework Directive guidelines based on high abstractions (Overton et al. 2014). Another example is Uganda where, in 2011, the Environmental Impact Assessment Guidelines for Water Resources Related Projects recognized environmental flows and subsequently the government has guaranteed environmental flows in water abstraction permitting, water release projects from hydropower, and dam weir design (O'Brien et al. 2021). As a final example, in 2005, China's Environmental Protection Administration required the release of environmental flows from hydropower dams and this condition has been included in the operation strategy for the Three Gorges Dam and other ministries’ policies (Cheng et al. 2018). These cases highlight consideration of water use caps and releases in countries’ regulatory frameworks but also suggest a need for greater community involvement in water use caps, licence conditions, and water releases.

From our synthesis, ecological reserves appear to be equally considered across environmental, cultural, and environmental–social flow initiatives in more decentralized governance contexts (Fig. 4). Horne et al. (2017d) describe ecological reserves as “legally establish(ing) environmental water as a prior right to consumptive water use.” Reserve determinations have been considered both in setting aside the required volume of water for an ecosystem or for release to an ecosystem and categorizing the waterbody based on the desired water quality class ahead of consumptive use and development (Pienaar et al. 2011; Brown et al. 2020). Either as part of an ecological reserve or independently, Aboriginal, Indigenous, or cultural reserved water rights have also emerged for Indigenous Peoples to protect and restore waterbodies for rights-based, cultural, and environmental uses (Jackson 2015; O'Donnell et al. 2022). The creation and legitimacy of ecological reserves has been supported through Indigenous title, protected areas, and co-management agreements (Costanza-van Den Belt et al. 2022). Recently, scholars have also described how ecological reserves require active management by environmental water managers and holders to release water to achieve environmental and cultural benefits (Horne et al. 2018). However, there are challenges with the implementation of ecological and Indigenous reserved water rights, including frustration by water users and governments because of delayed permitting and development decision-making (Pienaar et al. 2011).

We found that ecological reserves have been considered, for example, in Australia, Canada, Chile, Kenya, Mexico, New Zealand, South Africa, and the United States (Fig. 4). In South Africa, between 1999 and 2008, the government received 1600 requests for reserves and approved 900 (Pienaar et al. 2011), and recent strategic adaptive management processes, in the Crocodile River in South Africa, for example, emphasize transparent and cooperative management between the state, catchment management authorities, and stakeholders (McLoughlin et al. 2021). In Australia, the Murray–Darling Basin ecological reserve offers opportunity for Indigenous Nations to restore aquatic ecosystems, such as the floodplain of the Moorna State Forest, which is managed by the Barkindji as an Indigenous Protected Area (Jackson and Nias 2019). Similarly, Indigenous reserved water rights are in place for commercial use by Nations in some Northern Territory (Australia) water allocation plans, and there is opportunity for more ecological reserve designations and strategic planning (Jackson and Langton 2011; O'Donnell et al. 2022). In Mexico, the government released an ecological reserve program in 2012 for 189 river basins (Salinas-Rodríguez et al. 2018). In the United States, the Colorado River has wildlife refuges with entitlements and federal Indigenous reserved water rights, both of which act similar to a reserve in that a water apportionment is given each year ahead of consumptive uses and Indigenous water rights cannot be lost from non-use and are held in perpetuity (Butler et al. 2021). In Hawaii's Waihe‘e River, Waiehu Stream, Wailuku River, and Waikapu Stream, there is also recent use of the public trust doctrine to reserve water for the environment (Cantor et al. 2020). This doctrine has enabled Maui communities and lawyers to work together to restore rivers and have them run without diversion (Cantor et al. 2020). For both Chile (MacPherson and Salazar 2020) and Kenya (Richards and Syallow 2018), environmental flows or reserves for surface waters are prioritized ahead of commercial consumptive uses. In Canada, Nowlan (2012) mentions that environmental flows are considered through reserves, limits on licences, and water management plans. Lastly, in New Zealand, there are water allocations reserved for Māori, but these reservations can be relinquished if an allocation limit is met; therefore, Taylor et al. (2020, p. 36) recommend “Mana Whenua Mana Wai allocations” to support a clearer allocation hierarchy. While ecological reserves are becoming more common worldwide, our synthesis points to a need for more attention to the implementation of Indigenous and cultural reserved water rights.

In centralized and decentralized governance arrangements, there are opportunities for the purchase of water rights for the environment and culture in water markets (Fig. 4). These rights can then be traded by public governments, community cooperatives, and Indigenous communities where privatization of water rights is an established tradition. Water markets offer opportunity to adapt to demand and supply through water trade in both formal and informal and urban and agricultural settings (O'Donnell and Garrick 2019; Garrick et al. 2023). A water bank refers to a “network of inter-basin water connections” and transactions (Sheer et al. 2013). Rosegrant and Binswanger (1994, p. 1615) describe how “a system of marketable rights to water would induce water users to consider the full opportunity cost of water, including its value in alternative uses, thus providing incentives to efficiently use water and to gain additional income through the sale of saved water.” In the papers we reviewed, most water market schemes were created because of water scarcity and overallocation of water to licence holders. Purchasing water or issuing water licences based on cultural and environmental factors is in large part a response to the need to restore flows either immediately or through long-term storage. Water market schemes may be a way to experiment in decentralized forms of governance.

In our synthesis, we found that schemes to purchase water for the environment are present or proposed in Australia, Canada, Chile, the European Union, Mexico, New Zealand, Spain, the United Kingdom, and the United States (Fig. 4B). However, this is not an exhaustive list of formal and informal water markets; instead, these countries serve as some useful cases of water markets where Rights holders and stakeholders may have an active role. Australia has a long-established tradition of informal and formal water markets (Seidl et al. 2020). Effective water allocation and governance in Australia is suggested to be a product of water markets, regulation (2007 Water Act enables setting a sustainable diversion limit and establishes a Commonwealth Environmental Water Holder in the water market), and collaborative approaches (Crase et al. 2013; Pahl-Wostl et al. 2013). Environmental water managers in the Murray–Darling have had an active role in securing environmental water entitlements because of water buybacks from licence holders and efficient irrigation technologies (Garrick et al. 2012; Costanza-van Den Belt et al. 2022). Additionally, through increased recognition of co-governance in the Murray–Darling Basin, there is now emphasis on tradeable Indigenous water entitlements, water buyback by Nations, and an Indigenous water trust or partnerships with private water trusts (Jackson 2015, 2017; Jackson et al. 2020; Hartwig et al. 2023). However, other scholars report limited uptake of water entitlements and trade by Indigenous communities throughout Australia and in the Northern Territory in particular (O'Neill et al. 2016), and a lack of clarity about how cultural flows will be included in market schemes to support restoration, livelihoods, and rights-based activities (Moggridge and Thompson 2021). In the United States, Richter et al. (2020) reported that the most successful water purchases for flow restoration have been through funded non-governmental actors and a state water trust, which participated in two-thirds of transactions in the American West. Two examples of water trusts that work to recover water for the environment through market mechanisms include the Colorado Water Trust (O'Donnell and Garrick 2017a) and Washington State's Trust Water Rights Program (Hurst 2015). The Colorado River Delta Water Trust “secured over 6,000 acre-feet of water rights from farmers in the Colorado River Irrigation District in Mexico” (Kerna et al. 2017, p. 5). In Australia, the United States, and other countries, water trusts and environmental water managers have been successful in the short term at recovery of water for the environment and managing water through markets (O'Donnell 2017).

The papers in this review that mentioned legal personhood for rivers were generally related to environmental or environmental–social flows and ranged from centralized to decentralized governance settings, but this was a small subset of our review (n = 7; Fig. 4). Note that few papers explicitly related cultural flows and legal personhood, but this was likely a result of our small sample size. O'Donnell (2019a) describes legal personhood for rivers:

However, legal personhood does not grant a river a right to water for protection against extractive activities and extinction (O'Donnell 2020). An indirect form of legal personhood includes environmental water managers—“…organisations with legal personhood, which have been created to acquire and manage water for the aquatic environment” (O'Donnell 2017, p. 503). While environmental water managers hold decision-making power and have responsibility over the environment (Horne et al. 2017e; O'Donnell 2017), river rights conferred through legal personhood are represented by a “guardian or loco parentis who is the human face of the river and who interacts with the regulators…” (Davies et al. 2023, p. 405). Legal personhood for rivers is an opportunity to assert the inherent value of waterbodies; however, effective alignment with cultural flows and Indigenous water law is dependent on the guardianship process being localized and context specific (Davies et al. 2023).

Legal personhood of rivers has been enacted in Colombia (Río Atrato), India (Ganges and Yamuna; recently struck down), and New Zealand (Whanganui) (included in Fig. 4). Indirect legal personhood through environmental water managers is occurring in many countries (principally Australia and the United States but also, for example, Brazil, Canada, Chile, Ghana, and Mexico) (O'Donnell and Garrick 2017b; O'Donnell 2019a). Direct legal personhood for rivers has also been considered or recommended for the Colorado River and Lake Erie (United States), Ethiope River (Nigeria), Saint Lawrence River and Peace–Athabasca–Mackenzie River (Canada), Magdalena River (Mexico), the Margaret and Yarra rivers (Australia), Bangladeshi rivers, Chilean rivers, and rights for nature have also been recognized in Bolivia and Ecuador (Eckstein et al. 2019; O'Donnell 2019a, 2023b; Macpherson 2021; Cárdenas and Turp 2023). We note, as well, that the Magpie River in eastern Canada and the Marañón River in Peru were recently recognized with legal personhood, but this was not included in papers in this review. For those rivers that have direct legal personhood, New Zealand and Columbia follow collaborative approaches with co-management agreements to employ legal personhood to assert Indigenous rights and values and create alternative institutions within existing legal frameworks to govern the river, such as Te Pou Tupua (New Zealand) and 15 guardians appointed by the government and community organizations (Columbia) (O'Donnell and Talbot-Jones 2018; O'Donnell 2019b). In contrast, India's legal personhood put forward a competitive model, where most guardians are members of the government, there is conflict between human industry and environmental advocates, and there is an expectation of a dramatic change in river governance outside of the existing legal framework (O'Donnell and Talbot-jones 2018; O'Donnell 2019b). Similarly, environmental water managers in the United States are more collaborative, working to change attitudes of water licence holders ahead of securing environmental water (e.g., Colorado and Columbia rivers), whereas Australia environmental water managers are more competitive, operating as a large participant in the water market (e.g., Murray–Darling) (O'Donnell 2017). Taken together, legal personhood is an opportunity for water governance democratization to collaboratively protect environmental water, but there are challenges with assigning guardianship, participating as water users in water markets, and rivers having human rights but not the right to water and to flow.