Japanese Local Governments Recover Small Amounts of Phosphorus from Sewage Sludge for Fertilizer

More local governments in Japan are extracting phosphorus from sewage sludge for use as fertilizer. The country aims to reduce reliance on imported phosphorus amid increasing global prices linked to Middle East tensions. Phosphorus essential for crop cultivation is imported almost entirely from abroad by Japan.

Supply disruptions triggered by Russia's full-scale invasion of Ukraine in 2022 prompted the central government to promote fertilizer production from sewage sludge. The central government promoted the effort to strengthen food security. Eight prefectural and municipal governments nationwide had 11 facilities to recover phosphorus from sewage sludge at the end of fiscal 2025, according to the infrastructure ministry.

Of those, Tokyo began operating a phosphorus recovery system in January 2024 at its Sunamachi Water Reclamation Center in Koto Ward. The Japanese capital tested vegetable cultivation using fertilizer derived from recycled phosphorus. The effects of fertilizer derived from recycled phosphorus were comparable to those of conventional fertilizer, a Tokyo Metropolitan Government official said.

Tokyo plans nationwide distribution of the recycled phosphorus fertilizer from fiscal 2026 in cooperation with the National Federation of Agricultural Cooperative Associations, or Zen-Noh. The city of Fukuoka began operating a phosphorus recovery facility in April at its Seibu Water Treatment Center.

Fukuoka's Seibu Water Treatment Center facility can produce 300 metric tons of phosphorus fertilizer annually.

It is one of the country's largest phosphorus recovery facilities. Fukuoka's facility uses technology that gathers phosphorus from high-concentration sludge and achieves roughly the same recovery volume as conventional facilities while being only half their size. Japan's annual phosphorus demand stands at about 300,000 metric tons.

Sewage sludge generated nationwide in Japan each year contains an estimated 50,000 metric tons of phosphorus. Production capacity remains limited. The Sunamachi facility produces only about 70 metric tons of phosphorus annually.

"Production costs for recycled phosphorus are far higher than those of imports," a metropolitan government official said, adding that technological advances and public aid are key to cost reduction. The Japan Times reported these developments on May 10, 2026.