**Abstract**

Golf course closures in the U.S. have exceeded openings since 2006, creating an opportunity for reuse that maximizes ecosystem service. Flood storage potential on a former course in Ohio was evaluated as part of a planning process for its future use. Flow through culverts that historically provided an outlet for excess surface water to drain to an adjacent stream was reversed, reconnecting the stream to its floodplain. Installation of shallow monitoring wells, surface water and groundwater level monitoring, and mapping of flood events provided the data necessary to assess flooding and flood storage potential. This study illustrates two methods for estimating flood storage, a culvert flow model based on head differences between the stream and ponding on the former course, and a GIS flood volume model based on high watermarks. As much as 103 K cubic meters and as high as 2.1 percent of stormflow was stored on the former course on the surface for a given flood event, with additional storage in the subsurface. Ecosystem services associated with stormflow are also provided, including water purification, soil formation, and nutrient cycling.

**Keywords:** ecosystem services, flood storage, flood mitigation, surface water-groundwater interaction, golf course
