USGA Article on Wet Bunkers

The Saga Of Wet Bunkers

By Pat Gross, director, Southwest Region
August 5, 2014

                                                                                                                                                                 It happens just about the same time every year. Superintendents in the Southwest start to hear complaints from golfers about “wet bunkers.” One would think that the hot, humid weather over the past two weeks would have people concerned about the survival of putting green turf, but the sandy hazards seem to be a higher priority for some golfers.
There are several reasons why bunker sand tends to be wet during the summer, especially in the early morning hours:

1. More water is being applied to surrounding turf areas each night, some of which lands in the bunkers.
2. In some locations, it is necessary to occasionally water greens deeply – also called leaching – to flush harmful salts and sodium away from sensitive turf roots. Some of that water ends up in bunkers.
3. Older bunker sand that is contaminated with silt, clay and organic debris tends to retain more moisture than newer, cleaner sand.

A misguided suggestion that is often made is to just move the sprinklers so they don’t spray into bunkers. This is a bad idea. Golf course irrigation systems are designed with sprinklers spaced in a 60- to 65-feet triangular pattern to provide the most even irrigation coverage possible. Arbitrarily moving sprinklers ends up creating a wet spot in one area (where the sprinkler spacing is compressed) and a dry spot in another (where the sprinkler spacing is expanded).
Instead of reconfiguring the irrigation system, it is best to concentrate on bunker drainage, sand quality and maintenance with the following activities:

• Increase the frequency of raking and cultivation to help bunker sand dry quickly.
• Check that subsurface drain pipes in the bunkers are working properly and are not clogged with debris or tree roots.
• Check sand quality and replace sand as necessary.
• Make a visit to the golf professional to see if you are using the proper sand wedge for the type of sand at your course and maybe get a quick lesson to brush up on bunker play.

Pat Gross (pgross@usga.org)
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