 The Belknap Hot Spring lies to the southwest of the wilderness area, ejecting water at a rate of per minute with a temperature of .The Mount Washington Wilderness has unknown geothermal potential as there have been few holes deep enough to assess its geothermal resources.Silicic bodies of intrusive rock are typically greater in size than more mafic rock in shallow crust, but geologically young, silicic rock does not occur within the Washington wilderness area.