Since 1945, Ironhouse Sanitary District (ISD) has maintained sanitary services for nearly 47,000 Oakley and Bethel Island customers.  The district treats approximately 2 million gallons of wastewater daily at its treatment facility near Walnut Meadows Drive, north of Main Street in Oakley.  Reclaimed water is spread on fields ISD owns near the Oakley plant and the District-owned 3,600-acre Jersey Island.

The district’s unique name derives from Ironhouse School, a small schoolhouse that once served the families living in the rural area near Hotchkiss Tract. The school served much of the sanitary district's territory today, so when it came time to select a name for ISD, the Ironhouse moniker seemed a natural fit.