Editor’s note: This article was originally published August 21, 2014

Heads up, trail users.

The Ann and Roy Butler Hike and Bike Trail is closed to foot and bike traffic where it crosses Longhorn Dam.

The closure, from 7 a.m. to 5 p.m. daily, is expected to last until Sept. 15. In the meantime, a southbound lane of Pleasant Valley Road will be blocked to vehicle traffic and open to walkers and cyclists.

Two lanes of Pleasant Valley Road also will be intermittently closed to accommodate a crane. Bicyclists and pedestrians will be guided across the dam during those times.

Motorists are asked to use caution and be extra alert in the work zone.

Longhorn Dam was finished in 1960 to create a cooling lake for the Holly Street Power Plant and the Seaholm Power Plant. The dam also helps keep Lady Bird Lake at a constant level during floods.

Crews are doing maintenance work on the hydraulic system of the dam’s gates. The maintenance work was last done in 1993.