Abstract: Good golf course bunkers begin with a properly constructed bunker floor. I like them contoured to permit positive drainage.
Golf course bunker floors vary from flat to highly-contoured. I’m a proponent of gently sloped bunker floors that encourage gentle subsurface water flow directed toward drain pipes. Flattish bunker floors collect water or drain water slowly because they don’t have subsurface slopes.
Bunkers built by bulldozer during the 1970’s and 1980’s often suffer from flat bunker bottoms. These bunkers usually have drainage problems along with stone encroachment into bunker sand. They were built by pushing out earth, forming a flat surface then clean bunker sand was placed on top of the exposed gravel. These bulldozer cuts often scraped away good soil leaving a gravel layer with bunker sand added in uneven levels.
Often seen on municipal golf courses, these flat bunker bottoms require major reconstruction to fix. After we create a new bunker floor with a rounded shape, we add subsurface drain pipes along with 6 inches of silty material to form a stone barrier. Another option involves bunker liner installation but I’ve found that the costs are similar for both processes.
After we shape the bunker bottoms, we strip about 10 feet of sod around the new edge. On most of these courses, dramatic bunkers look out of place so we construct low and slow features that provide a clean, yet aesthetically pleasing sand hazard. By gently pitching the bunker floor we improve sand visibility while maintaining a subtle appearance.
When visioning a bunker renovation, start with rounded bunker floors, then add character mounding as needed.