Pat,
You are correct. And its mostly a new problem caused by the trend to part to part green heads.
Here is an article I wrote for Golf Course Industry explaining why part to part sprinklers put more water in the approach, and the simple fix of adjusting those part circle heads to something other than 90 degrees to reduce water in the approach.
Wet Approach Areas
By Jeffrey D. Brauer
I had the pleasure of golfing with Ron Whitten, Golf Architecture Editor for Golf Digest and Jim Moore, USGA Construction coordinator recently. Golf Digest is now emphasizing firm and fast conditions in their Top 100 rankings. This change comes just as Jim and I have noticed more and more courses experiencing overly wet green approaches, making for some interesting discussions on the golf course!
Better players are just now revisiting the joys of bump and run golf, but average golfers have always used/needed the run up approach to attain the green. When approach areas are wet, and approach shots plug, those golfers simply cannot hit a green in regulation. Green approaches should be considered high priority maintenance areas – equal to the greens themselves - and ahead of tees and fairways – if golf courses are going to play the way they are designed. Superintendents should maintain the green and surrounds as an interrelated complex, much as the golf course architect originally did during design.
I have address design aspects of wet approaches by contouring more greens to move more drainage away from the front of the green towards the sides, especially on larger greens with greater drainage volumes. I also contour most green approaches with 4% minimum slope (vs. 3% in other areas) while being mindful that too steep an approach slope will kill an approach shot just as surely as a wet one.
I recommend building sand capped approaches and fairway chipping areas on new courses. Existing courses can slowly create sand based approaches via aggressive core aerification and removal, together with heavy topdressing. While more expensive, reconstructing approaches with a 4-8” sand cap and a herringbone pattern of 4” tile or slit drains may be the ultimate solution.
Predictable bounces are important in the approach, so any drain pipes there require good compaction to prevent settling that will affect play. While catch basins in the approach area might affect play, they help drainage greatly by avoiding long surface drainage runs that always get soggy.
However, there may be a less expensive solution to quickly improve wet approaches on existing courses. Jim Moore is conducting research on wet approaches and sees evidence that overwatered approaches often stem from the golf course/irrigation design practice of using part to part sprinklers to achieve more precise watering of both green and surrounds.
The concept of part to part circles to water greens and surrounds is great in principle. Two old sayings – “the devil is in the details” and “There are always unintended consequences” seem in play here, as problems occur when irrigation designers place green irrigation heads at 8 and 4 (rather than at 6 or the center line of play) to reduce their affect on play and superintendents set those sprinklers at about 90 degrees to cover just the greens or just the approaches.
This combination of conditions results in four heads (six counting the approach heads) watering the frontal approach, rather than two or three that cover every other area of the golf course. And when considering that the “dwell time” – those few seconds that part circle heads stop before reversing direction – also occurs right in the approach, the approach inadvertently gets at least twice the irrigation of any other area on the golf course. Add in the traffic and compaction factors typical for approaches, and it’s no wonder they stay wet!Based on the preliminary study results, Jim suggests a few quick solutions:
• When replacing your irrigation system, consider placing the first head in the 6 O’clock position, accepting the very small risk of shots hitting the sprinkler.
• Use a combination of full Circle and part Circle heads around greens rather than part to part sprinklers. Only during summer heat and fall over seeding do the irrigation needs vary enough to warrant using the double heads.
• For the “outside” part sprinklers, adjust the spray pattern to reverse in a less critical area out in the rough rather than automatically setting them to 90 degrees that add unnecessary irrigation to the approach. Setting them to nearly full circle should move the dwell time area out in the rough, but you should also consider existing trees, heavy cart traffic areas, etc. and set them on a site specific basis.
• Make sure to constantly monitor and periodically adjust sprinklers, since they often come out of adjustment.
It’s ironic that part to part sprinklers, quickly adopted to address the problems of different water needs around the greens, have inadvertently added to the problem. With golfers continuing to demand better playing conditions in critical areas of the course, the new emphasis on firm and fast, and budgets being squeezed, you might try the laser surgery approach of adjusting your sprinklers.