The Japanese garden in Seattle

When a major water pipeline burst above the Japanese Garden in Washington’s Arboretum, large amounts of soil, oil, chlorine, and other contaminants were flushed into the garden’s ponds with valuable Koi fish. The contaminants threatened both the fish and the rest of the ecosystem.

Within the critical 24-hour period, treatment with chitosan and sand filtration was initiated. After two days of treatment, around one million liters of water had been treated, and the high turbidity in the water was reduced from 155 NTU to under 5 NTU after treatment. The treatment project ensured a better water environment for the fish and the ecosystem in the ponds. The reduction of suspended organic material also resulted in decreased problems with oxygen depletion in the water, something that had been an issue before. The park was able to reopen to the public with noticeable improvements in water quality.

This was the inaugural project where Swedish Hydro Solutions’ Jakob Sjöberg and John Macpherson worked together with chitosan treatment technology. The project marked the beginning of a close cooperation between Jakob and John, who later worked together for many years in the USA. This cooperation has been a key part of the establishment of Swedish Hydro Solutions.