In the water, sanitation and hygiene (WASH) sector, people from low-income communities are affected by inadequate sanitation facilities and the limited availability of safe drinking water. However, women and girls are disproportionately affected mainly because of gender inequality (Kayser et al., 2019; Sweetman and Medland, 2017). Society has constructed different roles for women and men, including in the sanitation and hygiene sector. In most rural communities, especially in areas where water is scarce, women and girls have the primary responsibility for collecting water and keeping sanitation facilities clean. Meanwhile, men who are socially perceived as breadwinners are responsible for decision-making related to WASH infrastructure construction and are not expected to do domestic errands such as managing water and sanitation (Assefa et al., 2021; Baker et al., 2018; Cavill et al., 2022). This difference in responsibility shows how gender roles are social constructs that place women in subordinate positions (Hentschel et al., 2019).

Nevertheless, WASH facilities and services often homogenise their users, making women's and girls' needs tend to be overlooked. Biologically and socially, women and girls have particular needs for proper conditions of sanitation facilities. Biologically, due to their menstruation, women and girls need different features of toilets to support them in managing their menstruation (Schmitt et al., 2017). Poor sanitation and hygiene facilities will harm their reproductive health (Corburn and Hildebrand, 2015). For instance, unimproved toilets increase the risk of infection of the urinary tract and reproductive organs, which can reduce women and girls' quality of life (Yadav and Bilas, 2016). Such a situation has long been recognized and has implications for demands for gender mainstreaming in the WASH sector.

As Sustainable Development Goals (SDGs) have mandated adequate and equitable access to sanitation and hygiene for all under goal number 6, the attention to women and girls in the WASH sector needs to be paid comprehensively through gender-sensitive programming (Bappenas, 2019; Carrard et al., 2022). WASH program is a strategic entry point for gender equity, women empowerment, and improving women and girls' health, while WASH program can also benefit with better outcomes using a gender sensitive approach (Leahy et al., 2017; Pederson et al., 2015; Tsetse and Alleman, 2017). In addition, recent scholarship emphasizes the need for more robust gender equality approaches in WASH programs to move towards truly gender-transformative practice by not only acknowledging gender differences, but challenging and changing the underlying power structures and social norms that perpetuate gender inequality (Caruso et al., 2024; MacArthur et al., 2023).

This paper scrutinises the implementation of gender-sensitive sanitation programs piloted in some eastern parts of Indonesia, mainly in Lombok Tengah, West Nusa Tenggara (NTB) and Manggarai Barat, East Nusa Tenggara (NTT). Eastern Indonesia particularly NTB and NTT are generally less developed compared to Western Indonesia, which is characterised by lower socio-economic status, lower education level, and low coverage of basic and WASH infrastructures. As of 2022, the prevalence of open defecation in some eastern provinces such as East Nusa Tenggara (NTT) remains above 20 %, compared to less than 5 % in most parts of Java (BPS, 2024; MOH, 2023). Moreover, in comparison to the national average open defecation rate of 3.2 % and the rural national average of 5.54 %, the open defecation rate in NTT is significantly higher (BPS, 2024).

These conditions are also reflected in the region's overall health status. The health status related to WASH experienced by women in this area is not only a product of limited access to infrastructure in the area (physical space) but more broadly the impact of the cultural context and socio-economic characteristics within the place.

Moreover, Eastern Indonesia represents a region with significant disparities in WASH access compared to urbanised areas of Java, for example, making it a critical case for understanding how place-based factors affect gender disparities in sanitation access. The areas have become the focus of many WASH programs delivered by the government and international organisations which provide more experience for the communities in various WASH program. In the districts, some schools in Central Lombok have constructed inclusive toilets, and women are actively participating as sanitation entrepreneurs. Although the involvement of women is reported, the engagement is still superficial and not in the strategic decision-making process (Indarti et al., 2019). However, the reasons for the level of women's engagement in sanitation programs are less documented.

Using a case study of the national sanitation program (Sanitasi Total Berbasis Masyarakat – STBM) in Eastern Indonesia, this paper discusses barriers to women's participation in sanitation at each socio-ecological scale using a gender lens. The STBM program in Indonesia is a local adaptation of the community-led total sanitation (CLTS) approach, which focuses not only on achieving an open defecation-free status for the community but also aims to change household behavior in hand hygiene, water and food safety, domestic solid waste management, and wastewater handling. Recently gender equity, disability and social inclusion (GEDSI) perspective was introduced to the STBM program and this was piloted by several organisations aiming for more equitable and inclusive sanitation outcomes. We elaborate in the following section on the theoretical frameworks that highlight the importance of scales in understanding the relationship of gender inequalities with “place” and its attributes related to space and context. Recommendations are made accordingly to address issues and determinants at each scale. The experience in those areas might assist practitioners in identifying determinants at different socio-ecological scales before designing sanitation interventions for achieving better gender outcomes.