The Sumida watercress farm near Pu‘uloa (Pearl Harbor), O‘ahu has been in continuous operation since 1928. This family-run farm (Figure 1a) produces 70% of the state’s watercress crop, making it critical to Hawai‘i’s food production. The farm’s watercress relies completely on water from freshwater springs. However, the amount of water flowing from the springs has declined by half over the last century as a result of groundwate...

Summary Enhanced biological phosphorus removal (EBPR) exploits the metabolism of polyphosphate‐accumulating organisms (PAOs) to remove excess phosphorus (P) from wastewater treatment. Candidatus Accumulibacter phosphatis (Accumulibacter) is the most abundant and well‐studied PAO in EBPR systems. In a previous study, we detected polyphosphates throughout peripheral bay sediments, and hypothesized that an estuary is an ideal set...