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How To Rebuild Eroding Bunker Faces
by Stanley J. Zontek,
Director, Mid-Atlantic Region, USGA Green Section
first published in the Green Section RECORD, May/June 1983
How many times have you read a magazine article only to
find very little new information passed your way? I hope when you
finish reading this one, you'll say, "Wow! Now there's an idea I'm
going to try!" You see, this is a "how to" article: how to rebuild
and improve the shallow, eroding faces of sand bunkers.
A fairly common problem on those golf courses that have the newer,
shallower-type sand bunkers of more contemporary design occurs because,
as originally constructed, these sand bunkers are radically different
from the older, deeper and more classical bunkers with which we
are familiar. The old style bunker design incorporated a relatively
flat sand base with grass banks extending down to the sand.
The new style bunkers are much shallower (and even elevated for
visibility in some cases) and have the sand extending or flashing
up the bank. While this type of bunker design is attractive, quite
visible and relatively easy and efficient to maintain, it does have
some built-in maintenance problems. Foremost among them is erosion.
Diagram I shows a cross section of this type of bunker.
Water, whether from rainfall or irrigation runoff, travels down
a grassy sloped surface, into the bunker, through the sand on the
face and to the native soil underneath. When the water hits this
tight, heavy native subsoil underlying the sand, it moves down the
slope - carrying the sand with it and causing erosion.
Under normal irrigation or rainfall, little sand is moved. However,
when heavy and intense rainfall occurs (as in thunderstorms), large
amounts of sand can be moved off bunker faces, and the golf course
superintendent and his crew have the chore of hand-throwing or pushing
the sand back up the slope of the bunker. Besides being labor intensive,
the sand readily becomes contaminated with subsoil, and it doesn't
take too many of these washout/ replacement cycles to badly contaminate
and dirty the sand. This detracts from the appearance of the bunker.
Also, this dirty sand has different playing characteristics, and
dirty sand grows more weeds, too!
It is not my intent to compare or criticize different sand bunker
designs. Rather, I would point out that there is a technique that
can be utilized, within certain limits, to reduce maintenance and
improve the appearance and playability of this type of bunker design.
Diagram II shows a plausible and practical solution to the problem.
The underlying subsoil on the slope of the bunker is dug out and
removed to form an approximate 90-degree angle between the bottom
of the bunker and the edge of the hazard.
In essence, a vertical wall is formed from two feet to four feet
high. The sand is replaced, matching the original design and slope
of the bunker. The process is then complete.
Bob Holmes, Superintendent at Lafayette Country Club, Lafayette,
Indiana, illustrates this technique during the renovation of some
of the bunkers on his course:
Step 1 (Figure I). The eroding
bunker face and its dirty and contaminated sand are
removed mechanically, and the bottom of the bunker is
leveled and squared off. To make the earth and sand
removal quicker and easier, a small frontloading tractor
is used.
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Step 2 (Figure II). An employee
is truing the cut and edge of the bank with a spade.
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(Figure III). The finished job:
a clean, neat wall ready for sand replacement.
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Step 3 (Figure IV). The completed
job with the sand replaced, smoothed and raked.
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Bunkers constructed in this manner will look better and the sand
will definitely stay in place better. This will reduce sand / soil
contamination and alleviate the seemingly endless job of replacing
washed-out sand after every heavy rainfall.
As with almost everything we do on a golf course, there are some
limitations to this program. For example, there seems to be a limit
on just how deep a cut can be made and how far the sand can be pushed
up the face of the bunker. For one thing, this technique requires
substantial amounts of sand, and the greater the elevation and cut,
the more sand needed. Obviously, in areas where sand is expensive,
this can become an expensive project.
Another consideration is that deep sand on the face of the bunker
tends to be relatively soft and, under certain conditions, golf
balls may plug and even bury on these faces. From a practical and
playable point of view, there is a limit of approximately three
to four feet on the depth of the sand. Within these limits, however,
this procedure seems to work very well.
The old nagging problem of eroding sand on bunker faces now has
a relatively simple solution. Where this rebuilding and renovation
technique has been used, better looking and better playing sand
bunkers have been built with resulting lower maintenance costs.
Now after all, isn't that what you were really looking for? A new
idea that works!
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