MMSD Jones Island

Thousands of acres of rice marsh and an ecologically rich freshwater estuary supported numerous Native American villages with fish, game, and wild rice. The last Native American inhabitants were the Potawatomi. In 1957 it was the original mouth of the Harbor, home to industry, shipyards, and neighborhoods. Jones Island is named after Captain James Monroe Jones who built a shipyard on the western side of the island.

& Facts


MMSD is a regional government agency that serves 1.1 million customers across 28 municipalities. Built in 1926, this plant is on the National Register of Historic Places and is the oldest activated sludge plant in the US, and can handle flow rates up to 330 million gallons per day.


To save costs, MMSD was one of the first plants to create a marketable product with the biosolids leftover at the end
of the water reclamation process – Milorganite! Popular spot for a Doors Open tour.

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