Longwood’s Summer of Spectacle – Fabulous Fountains Return. Flowing through the geothermal piping system is Houghton’s SAFE-T-THERM® HD. Head to Longwood Gardens in Kennett Sq outside Wilmington, DE and watch the Summer Spectacle. https://longwoodgardens.org/events-and-performances/events/summer-spectacle #glycoldelivery