This bridge is part of the infrastructure planning for the High Desert. Currently, there are only two bridges across the river for the Victor Valley. One is at Bear Valley Road and the other on highway 18.
There is also funding for a RR grade underpass at Ranchero Road in Hesperia. That, combined with a bridge at Rock Springs will generate a much higher volume of traffic to the Marianas of Apple Valley and Hesperia Mesa as residents take this new route to avoid the chronic gridlock on Bear Valley road.
It's going to happen. Probably sooner than later.