Engineering education is critical for sustainability, given the key role that engineers have in shaping the development of our society. Yet, engineering studies have traditionally not been driven by sustainability-related knowledge and skills, but focused more on general computational skills and technical problem-solving. This has also been the case in our case study, which focuses on recent water and environmental engineering graduates in Finland. We studied the role that sustainable development has had in their education and early career through an extensive questionnaire and semi-structured interviews. The analysis was done in two ways: indirectly by comparing how well the key working life knowledge and skills recognized by the respondents correspond with sustainability-related skills, and directly by studying the graduates' views towards the sustainable development and their possibilities to advance it in their work. The results show that although sustainability was not at the core of respondents' studies, their key competencies correspond well with sustainability-related working life skills. The respondents also see that sustainable development has a central role in water and environmental engineering, although it is typically more visible at a strategic rather than a practical level. However, the results also indicate that several early-career engineers have deficient knowledge of sustainable development, and are therefore lacking the ability to fully connect the principles of sustainable development into their own expertise. Overall, the findings suggest that water and environmental engineers with their wide set of competencies have the potential to take on a larger role in building a more sustainable society. To ensure this, engineering education should emphasize the connection between the field and sustainable development and clearly link engineers' core competencies with the skills required to promote sustainability.