B A Steinhagen Reservoir is located near the town of Jasper, Texas in the east Texas Piney Woods at 30.85 North Latitude and 94.19 West Longitude. The borders of Tyler County and Jasper County are defined by the bed of the Neches River, and therefore bisect the lake on a North/South line. The lake was created as part of a project that focused on creating lakes for recreation, power generation, and water conservation on the Neches River and the Angelina River. For many years, locals have referred to both the lake and dam as "Dam B".
The lake is bisected by U.S. Highway 190 very near its center-most point. Martin Dies, Jr. State Park is located on this lake.