Model of the Hoover Dam Bypass located at the Dam's visitor centre
When major development takes place within the park, it is necessary to revegetate the disturbed areas following construction. The purpose of such work is to both reestablish a native plant community resistant to invasion by weeds, and for it to be similar enough in species composition to the adjacent undisturbed areas that it will successfully blend into the local landscape.
Typically at Lake Mead NRA such projects have been to revegetate the disturbed right of ways left over following road construction. The two photos at the left date from the mid 1990's during construction on Lakeshore Road. This is actually the project which served as the genesis of Lake Mead's native plant nursery. At the time there was no such facility. Seeds were collected and sent to the nursery at Joshua Tree National Park, where they were grown out and brought back. After the return of the plants, a temporary facility was set up to care for them while they were waiting to be planted. This then evolved into the Lake Mead Native Plant Nursery.
The photo up above is of the model of the Hoover Dam Bypass, a project currently underway in the park. The purpose is so that traffic, which currently passes on a road along the top of the Dam, can cross the Colorado River without slowing down. A similar a structure already exists upstream at the Glen Canyon Dam (which forms Lake Powell). The Hoover Dam Bypass had been planned for some time, but became more of a priority following the attacks on September 11th 2001, in order to improve security on the Dam. Completion is currently scheduled for 2008. The primary disturbance is not the bridge itself, but the roads on either side that provide access to it