“Why is the sand in this bunker hard and the last one was soft?” My guess is just about every golfer has either uttered something like this or been in a group with someone who has. It is common for bunker sand to play differently from course to course and even from bunker to bunker on the same course. It can be confusing why this happens, especially since it all may look like the same white sand, but there are a number of factors that will always keep sand from playing exactly the same.

Environmental Conditions

The impact that the environment has on a golf course cannot be overstated. While sun, wind and rain are most often mentioned in discussions about turf conditions, they also influence how bunker sand plays. For example, a bunker exposed to full sun that gets plenty of air movement will dry out faster than a shaded bunker. Sand that is drier tends to play softer and moist sand plays firmer. Minor differences in orientation to the sun, tree shade or wind direction can lead to noticeable differences in how bunker sand plays from one location to another.

Sand Type

Not all sands are created equal. There are many sands on the market and comparing an expensive manufactured sand to a lower-cost natural sand is like comparing apples to elephants. A manufactured sand may pack together tightly even when dry and will usually drain better than natural sands. It is also likely to be more consistent across a golf course. This does not mean that there is anything wrong with lower-cost sands, the point is simply that different sands are going to play differently and you can’t always tell one sand from another just by looking at it.

Construction

Just like all bunker sands are not created equal, neither are all bunkers. Some bunkers take on surface water, while others are shaped to deflect it away from the sand. A bunker that water flows into when it’s raining will stay wetter longer and play firmer because more water reaches the sand and because the sand is more likely to become contaminated by dirt and debris that interfere with proper drainage. Bunker shape also matters – a flat-bottomed bunker will hold water differently than a bellied bunker, affecting how firm it is after rain.

Another bunker trait that affects playability is the presence of drainage. Without subsurface drainage, water will sit on the floor of the bunker until it naturally absorbs into the soil, evaporates, or is pumped out by the maintenance team. The longer a bunker stays saturated, the firmer it will play. One final construction feature that impacts bunker conditions is the presence or absence of a liner. Some liners are designed to aid drainage while others may cause the sand to hold moisture.

Maintenance

Some golf courses prefer a very intense approach to bunker management while others choose to focus more of their resources elsewhere. Bunkers that are raked daily will be less firm than those raked a few times per week, but different bunkers are often maintained at different intensities on the same course. For example, some courses will fully rake greenside bunkers daily and only touch-up disturbed areas of the fairway bunkers. A fairway bunker that hasn’t been fully raked in a few days will often play firmer than a greenside bunker on the same hole.

There are also variations in raking methods that can impact how the sand plays. A bunker that is hand-raked could be “fluffier” than one raked with a machine. The added weight of the machine will compress sand, especially when it’s wet or damp, making for a firmer surface. Irrigation coverage also plays a role. It is unavoidable that some bunkers will get water from the sprinklers, keeping that sand firmer – especially if the course waters frequently.

Play

One of the biggest factors in sand variability is the amount of play bunkers receive. The sand in bunkers that see a lot of action gets raked and shifted around by golfers more often. This can cause the sand to play softer. Bunkers that don’t get much play are usually firmer, especially if the maintenance team rakes them less frequently.

Conclusion

Bunker sand variability isn’t just something we see during a weekend round on our favorite course, it is also a common concern in championship golf. When I’m working at a USGA championship, we often take steps to improve sand consistency throughout the course, and this is at venues that already invest lots of resources into bunker maintenance. Despite our best efforts, we still hear comments about one bunker playing differently than another or the sand at this course playing differently than one down the road. That is simply the nature and challenge of bunkers, you never quite know what you’re going to get.