A virtual gauge has been developed for the Lost based on the Brandywine gauge on the South Fork, South Branch Potomac and Cootes Store gauge on the North Fork Shenandoah all in cfs. The ranges for this upper stretch of the Lost River (above WV55) are 320 - 1,500 cfs at Brandywine, 540 - 2,600 cfs at Cootes Store and 300 - 1,450 cfs for the Lost River virtual gauge. The great Cacapon gauge is too far downstream to be at all useful for the Lost and the Moorefield gauge on the South Fork of the South Branch of the Potomac is best ignored for this run.
There is a painted gauge on the Route 55 bridge, west side abutment. For the upper Lost (above the WV55 bridge), a level of 0 to 3 feet is good, though it can be run a little bit below zero. Construction of the Corridor H highway may ultimately change this gauge. Report observations here.