###### Abstract
In Portugal, companies providing water supply and wastewater sanitation services are designated as managing entities. Its management model can be of the type of direct service provision, delegation of service to a company, or even its concession [16]. For most of the Portuguese population, the complete sanitation system is adopted, from collection in buildings to proper disposal in the receiving water environment, the collection rate is very close to the wastewater treatment index. However, there are important regional asymmetries in terms of water availability [17]. In this context, the implementation of water production systems for reuse is increasingly important as a way of minimizing pressure on water bodies in the country. The reuse of water is part of the planning of water resources in Portugal provided for in the National Strategic Plan for the Water Supply and Wastewater Sanitation Sector [18] that was in force from 2014 to 2020. Thus, although the use of treated wastewater for various purposes is seen as a central axis of sustainable management of water resources, there is not, even in regions of greater water scarcity, a widespread practice of using urban wastewater in Portugal [16]. Centralized treatment systems are inefficient in treating wastewater at reusable levels. Furthermore, it has been reported in the literature (for example, the work of [19]) that large, centralized treatment systems that require more electricity are not a sustainable option due to the intermittent power supply and insecure resources for operation and maintenance. Therefore, wastewater treatment must be performed in a regional context, close to its point of generation. Decentralized approaches allow not only treat wastewater but also allow the reuse of water and nutrients, as well as energy efficiency, as wastewater is rich in nutrients. Wastewater treatment plants (WWTPs) perform the important task of mitigating environmental impacts caused by organizations and households at the end-of-pipe. They focus on the operational environmental performance either regulated by laws, contributing to financial savings, or increasing customer satisfaction [20]. However, the literature so far falls short on evaluating these companies' own financial performance and economic sustainability. Evaluating the economic sustainability of any business is important because it affects firm survival in the market. Therefore, it compromises the recycling chain necessary for the environmental sustainability of a given economy. In other words, economic viability performs as a substantial barrier to the implementation of a resource recovery technology [21]. On the other hand, the exploration of the system symbioses across neighboring waste generation sites allows tackling the environmental issues faced by the generation of wastewater [21]. In addition, worldwide water scarcity requires the integration of water policy in the circular economy (CE) to improve the quantity and quality of water by promoting its reuse and optimizing the amount of energy, minerals, and chemicals used in the operation of water systems [22]. In this context, a stream of literature estimates the market value of water to drive water savings to a circular paradigm, to improve economic and environmental decision making [23]. However, most small, and medium enterprises (SMEs) face specific challenges, such as access to finance and difficulties implementing the CE [24]. Therefore, the process of the implementation of CE should start by managing change within the organization [25]. This is only feasible if the organization is economically sustainable. Accordingly, the regional agendas aim at identifying opportunities for accelerating and transitioning to more efficient and sustainable use of resources and reconciling together with regional stakeholders [26]. Yet, despite the establishment of the Green Deal by the European Commission in 2019, political progress has been tenuous in terms of achieving long-term sustainability goals [27].