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The unseen workforce behind wastewater management

High-income countries often take the wastewater management process for granted. Yet only 58 per cent of the world’s domestic wastewater is safely treated, with significant variation across regions. For World Toilet Day, we delve into the data to gain a better understanding of employment in the water collection, treatment and supply and sewerage industries in different country contexts.

A small workforce with a large impact

This blog focuses on workers in the water collection, treatment and supply and sewerage industries based on the International Standard Classification of Industries 4 (ISIC) divisions 36 (water collection, treatment and supply) and 37 (sewerage). These workers constitute only a subset of the global sanitation workforce, as there are indeed a far larger number of cleaning and sanitation workers employed across other industries. Cleaning and sanitation workers, whose critical role was further highlighted during the COVID-19 pandemic, was identified as a key occupational group in the ILO’s World Employment and Social Outlook 2023: The value of essential work. While the latter report discussed various aspects related to decent work for these occupational groups, the emphasis here is on the human resources involved in wastewater treatment and sewerage activities across the world, and what employment patterns reveal about the structure of these industries and implications for these countries’ potential to meet SDG 6.3.1 targets.

Unfortunately, the number of countries with available labour force survey data for these industries, and for sewerage activities in particular, is quite limited. This is partly because workers in the water collection, treatment and supply and sewerage industries represent a very small share of the workforce, with less than one per cent in all but one country with available data. Additionally, we find that while employment growth rates have been positive in recent years for most countries (in 31 out of 40 countries with two available non-consecutive data points between 2003 and 2022) for water collection, treatment and supply, there has been a decline in employment in several countries for the sewerage industry (specifically, in 8 out of the 14 countries). This decline may be attributable to restructuring of the industries, and a shift to less labour-intensive processes.

Also noteworthy is the correlation between the employment share in water collection, treatment and supply and sewerage industries and the proportion of safely treated domestic wastewater flows (SDG indicator 6.3.1) across country income groups. That is, in upper-middle- and high-income countries, where these industries are more capital-intensive, a lower employment share in these industries is associated with a higher proportion of safely treated domestic wastewater flows, while the opposite is true, on average, in low- and lower-middle-income countries, where labour intensity is higher and labour productivity is lower.

Occupational structure of the workforce: same industry, different composition?

The structure of these industries is reflected in the occupational distribution of the workforce. Specifically, in upper-middle- and high-income countries, the largest occupational category is that of technicians and associate professionals, which includes water treatment plant operators but also civil and mechanical engineering technicians.

On the other hand, the largest occupational groups for low- and lower-middle-income countries are the crafts and related trades workers, specifically plumbers and pipe fitters, and elementary occupations, including cleaning and sanitation workers (e.g., cleaners and helpers in offices, hotels and other establishments, and refuse workers), but also meter readers and civil engineering labourers. The share of plant and machinery operators and assemblers, which includes heavy truck and lorry drivers, is also relatively higher in low- and lower-middle-income countries.

Women represent, on average, approximately 20 per cent of the workforce in these industries. By occupational group, women account for approximately a third of technicians and associate professionals and, among upper-middle-income and high-income countries, they typically represent between 55-60 per cent of clerical support workers.

Despite limited data availability, there is some evidence of shifts in occupational structure that point to structural change within these industries. For instance, the share of elementary occupations in these industries declined in 15 out of 18 countries (between the last and more recent year for which data are available for each country between 2003 and 2022), while the share of technicians and associate professionals increased in 9 out of 18 countries.

Work quality: same job, different conditions?

In the water collection, treatment and supply and sewerage industries, the share of employed persons who are employees is relatively high and informality is much lower than the national average for most countries with available data. This is the case using both the ‘production unit’ approach to measuring informality (i.e., share of employment outside the formal sector) and the ‘nature of job approach’ (i.e., share of informal employment).

However, the share of employees is low and informality is high in the low-income countries for which data are available (e.g. Democratic Republic of the Congo and Ethiopia) and in some of the lower-middle-income countries (e.g. Kenya and Lebanon). There are also cases where the share of employees is low but informality is high nevertheless, due to the nature of the job/ contractual arrangements (e.g Thailand and Senegal) or to both the nature of jobs and prevalence of informal sector enterprises (e.g. Myanmar). Higher informality is associated with lower average wages in these industries, in comparison with the national average for each country.

The potential of SMEs

In the subset of countries with available data on employment by firm size, there are interesting differentials across geographical areas. In the water collection, treatment and supply industry in most countries in Latin America and the Caribbean, large enterprises (of over 50 employees) account for the highest shares of employment. Additionally, in a few countries (e.g., Bolivia and Ecuador), there is also some employment in microenterprises (of less than 10 employees). On the other hand, in Southern Europe and Central Asia, there is a relatively higher share of employment in small and medium enterprises (SMEs), defined here as having 10-49 workers. SMEs also account for the largest share of employment in the sewerage industry in the only two countries with available (reliable) data disaggregated by enterprise size for this industry (Japan and Italy).

The type (and size) of enterprises is certainly associated with the industries’ labour productivity and therefore with wages and working conditions. As SMEs are known to face specific obstacles to productivity growth and sustainability, these findings suggest that there could be major gains for employers, workers and society as a whole from support to SMEs operating in these industries.


This analysis revealed major gaps between the structure and composition of the water collection, treatment and supply and sewerage industries across countries. Despite some evidence of structural change in a number of countries, these differences, reflected in employment patterns, suggest that many countries and regions are currently left behind on yet another SDG target. For these countries, there is an urgent need to develop strategies – in line with just transition principles – to support enterprises and workers in these crucial industries, including through investment in infrastructure, equipment and importantly in human resources. Such policies can go a long way to boost productivity, improve working conditions, and strengthen the impact of this small, often invisible, but indispensable workforce.


  • Souleima El Achkar

    Souleima is an economist and labour market information specialist, with expertise in skills development systems. Since 2010, she has been working as a consultant on various projects for the ILO, Asian Development Bank and the World Bank.

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