Women scientists have historically been subject to direct and indirect discrimination. This opinion piece argues for a history of freshwater science that recognises the scientific achievements of women. It suggests that lack of opportunity for women scientists in the 20th century is typified by the stereotype that women were naturally predisposed to non-intellectual pursuits and, therefore, ill fitted to science. Freshwater science in Britain possibly provided a distinctive space for women in science, in spite of widespread lack of opportunity. Over 20 women scientists were working in one institution in the inter-war period, and during and immediately after the Second World War. Yet, outside of that specific context, their work is barely known. We give examples of these women and their work and argue that the historical invisibility of women in aquatic sciences needs to be more thoroughly addressed, so as to understand the work of women scientists as having historical, social, as well as scientific, significance.