Greenkeeping6

Ask any golfer to comment on thehealth of his or her golf course and intheir reply it is odds-on that bunkers

will be identified for treatment. Is this anotherexample of the well-known ‘Augusta Effect’?Or is it true that bunkers are often unfit forpurpose, justifying investment to aid recoveryor restoration? Engineer Richard Allenfollowed his passion and altered his careerpath, examining and analysing the causes,rather than treat the symptoms of bunkerailments. This report presents a shortsummary of some of the key findings andlessons learned over the last 10 years ofinternational bunker construction.

‘All bunker styles, apart perhaps from theshallow dish, produce maintenance tasks,sometimes disproportionate to theiradvantages.’ F.W.Hawtree. The Golf Course,1983.

This very accurate and efficient statementprovides a clue to the origin of the inventionof synthetic bunker revetments. When a well-respected, established local golf club beganconverting their irregular shaped, high edged,sand faced bunkers into flat shallow dishes,Richard, a lifelong golfer, wanted to know why.It emerged that the club’s greens’ committeehad taken the firm view that the aestheticvalue of these ‘Colt’ style bunkers was notworth the extra maintenance cost.

Disappointed by the outcome, Richardemerged determined to find, and if necessaryinvent, construction methods which wouldmake a range of bunker styles with affordablemaintenance regimes available to all golfclubs. The timing could not have been better.For some unknown reason, the golf industry,which has done wonders in agronomy overthe past decades, by comparison, had notpaid a great deal of attention to bunkerconstruction and maintenance. Soon after theturn of the millennium, however, new bunkerproducts, improved fabric liners and thenpioneering ‘hardscape’ options wereemerging fast. Golf clubs appeared to beeager to adopt new bunker technologies, sothis was a great opportunity. Or was it?

In Richard’s view the mechanics of how abunker performs are complex. There are somany variables in the site, materials, localground conditions, amount of play … the list

is almost endless. However, there are threedistinct aspects, which if all addressedcorrectly, should lead to consistent,aesthetically pleasing bunkers with anacceptable maintenance burden. Theseaspects, which are often interlinked, aredrainage, sand purity and edge construction.

Drainage“Pete Dye once told me that 95 per cent ofthe job is making drainage look good, andthere’s a lot of truth to that.” Tom Doak.

Richard’s professional background is as acivil engineer who specialises in drainage,flood risk analysis and developmentinfrastructure design. A key skill in this field isthe ability to design infrastructure that can beeasily maintained. Why? Because much of theinfrastructure is built privately, but with theultimate aim of a handover to councils ordrainage agents under relevant Acts of

end of season renovationt

Autopsy of a bunkerAs technology has improved dramatically over the last 20 years, does bunker maintenancestill have to be costly and time-consuming? ‘Absolutely not’ says engineer Richard Allen,who details key findings he has learnt from working on major bunker construction projects

Building a fully sealed EcoBunker

Edge contamination has been underestimated

Parliament (for example The Highways Act1980 or the Water Industry Act 1991).Councils must be wary of adopting expensiveliabilities, so the original designer (Richard andhis team) must be able to design efficientlybut also with maintenance and whole lifeperformance at the forefront of their minds.How has this skill been applied to bunkerdrainage?

‘All in all, since golf is played on many sitesother than the ideal light sandy soils of heathor links land, drainage is still a far moreimportant factor, in relation to all-year-roundplay, than almost any other consideration.’Jim Arthur. Practical Greenkeeping, 1997.

Flooded bunkers are an extremelycommon sight for golfers.

Furthermore, due to the current rules ofgolf they present extra problems. Competitioncommittees are often faced with the highlyunsatisfactory option of temporary rulings,even in major amateur and professionalevents, where bunkers are so full of water thatthey cannot afford relief in the conventionalmanner. Given the observable changes inweather, with more, short intense downpours,this phenomenon is likely to increase, unlessbunker drainage is improved.

Richard believes that applying a fewinexpensive standard engineering industry

techniques would help greatly in manyinstances.

The first one is simple: Having immediateaccess to as-built drainage plans. It issurprising how many golf courses don’t havean accurate plan of where their drainage is, orif they do, it can’t be found when it is needed.Sometimes all the information is accuratelystored in the memory of a long-servinggreenkeeper, but what happens if he is onholiday at the time of an emergency, orworse, retired or moved on to a newopportunity? Many man and machinery hoursare wasted alongside a flooded bunker as thelocation of the outfall is debated, andunsuccessful messy exploratory holes aredug. If an as-built plan is not available, muchmoney can be saved by a short-terminvestment in a drainage survey. Furthermore,with the advent of GIS and mobileapplications, it is then relatively easy forgreenkeepers to update their digital recordsas drainage networks are altered or extended.

The second is designing for easy accessand inspection. If there is no easy access tothe positive drainage and outlet, it is usuallydifficult to quickly determine the cause of thebunker ponding. Time is money, so a rapididentification of the problem is preferable, andit can help return bunkers to play much morerapidly, benefitting the paying customers.Accessibility can be achieved very easily bythe addition of mini inspection chambers androdding eyes. Richard has incorporatedrodding eyes and inspections chambers onhis projects (they only cost between £20 and

£50 each) and is surprised how rarely heencounters them on the many site visits heundertakes. “This simple approach allows thegreenkeeper to quickly determine if the pipeis flowing and ensure it is clear. The problemcan often be solved this way with no mess orwasted time. If the pipe is clear but notflowing then the problem is that water is notentering the pipe, so only then will moreintrusive, time consuming work within thebunker be necessary,” he said.

Finally for golf courses which rely onsoakaways, but where infiltration potential ismarginal, Richard recommends that wherespace is available the soakaways are locatedoutside the bunkers. If the soakaway is underthe flooded bunker it is impossible todetermine what the problem is withoutundertaking excavation. On the other hand, ifthe soakaway is easily accessible it can bequickly determined whether the soakawayneeds de-silting, or the pipes are blocked, orthe pathway from bunker sand to outlet iscompromised. The uncertainty is removed,ensuring that remedial efforts are focussed onthe correct solution straightaway. Richard alsorecommends simple inexpensive infiltrationtests, which if carried out using establishedengineering procedures (BRE Digest 365)can help with the design of soakaways,appropriate to the site. “This takes the luck outof soakaway construction,” he commented.

Sand purityBunker sand is expensive. And it is not likelyto get any cheaper in the future. Most golfclubs will be aware that many of the sand

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8 Greenkeeping

Secession Golf Club’s 16th hole during HurricaneMatthew. Right: How it looked three days laterSTRI judged Richard’s drainage design to be water

management project of the year

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quarries in the UK that used to deliver topquality bunker sand have closed. Sand needsto be delivered longer distances, greatlyincreasing the cost. This is not only a UKphenomenon. A technical article in TheConversation on September 7, 2017, predictsa worldwide sand shortage. At current rates,Vietnam, for example, might run out ofconstruction sand by 2020.

Cost is not the only concern.Contaminated bunker sand doesn’t drain aswell, stones in bunkers are an unwantedhazard, much complained about, aestheticsare compromised and consistency (a wordoften uttered by disgruntled golfers) is moredifficult to achieve. Therefore we should belooking at ways to extend the life of the sandwe install into bunkers. How can this bedone?

Traditionally it was thought that allcontamination came into the sand frombelow. This is not 100 per cent accurate, butnevertheless, a whole new industry in bunkerliner products has grown, and seeminglyaccelerated over the past 10 years. Some soilconditions mean that a liner isn’t needed, butusually, if a golf club wants to extend the lifeof their bunker sand they will need a liner ofsome sort. How do you choose which one touse? In Richard’s view this is a difficultdecision because the choice is now so wide,and so is the price range but, followingworking with most of the main liner productson the market he feels able to give someadvice: “It’s possible to split the market intotwo segments: geotechnical fabrics andaggregate based ‘hardscapes’. The fabrics are

a lot cheaper to buy, and can be installedeasily in-house, but they have developed apoor reputation. In most instances this isunfair, because they will normally performvery well if a minimum cover of sand ismaintained in accordance with themanufacturer’s specification. This requiresregular monitoring of sand depth andadjustment. If a golf club doesn’t have theresources to carry this out consistently then itshould probably consider alternatives, but itshould be noted that some of the world’sleading courses manage very well with fabricliners,” he explained.

Turning to the hardscape options Richardcommented: “These are generally moreexpensive, and some can only be installed bythe proprietor. In the long run though, theymay not work out quite as expensive as theyseem, because as a whole they do requirevery little maintenance. There have beensome failures in the past, but the industrynow seems to have learned from this, andsome products come with generouswarranties. This added reassurance issomething I would look at if it was my golfcourse.”

EcoBunker, Richard’s company, isindependently arranging and installing linertests for clients that wish to compare theperformance and member feedback oncontrasting options at their golf courses. Linersare a major investment, so spending arelatively small sum on a trial may be aprudent way forward for a golf club.

Bunker edges and facesReferring back to the start of this report, theunfortunate removal of bunkers with raisedlips and irregular shapes was the spur that ledto Richard’s invention of the method oflayering synthetic turf to form resilient but

natural looking bunker edges. What benefitsdoes this edging system bring?

Firstly, combining a resilient, permanentedge with an undersand liner creates a sealed‘tank’ which drains water but retains the sand.Sand purity is extended, as silts and stonescannot enter the bunker for the sides. Thiswas an underestimated source ofcontamination until ‘stacked synthetic sod’, asit is termed in the USA, entered the scene.

Secondly, the costs savings areconsiderable, on all styles of golf course. Forexample, its widely known that natural turfrevetments only have a practical lifespan offour to five years. By contrast, the EcoBunkersystems are guaranteed to last for 20+ years.Southerndown Golf Club (pictured above)was the first golf club to commit to a fullcourse renovation back in 2012. Having nowcompleted the last of 80 bunkers in thespring of 2017, the club is now collecting datathat proves it is saving the predicted £20,000per annum on bunker maintenance.

Finally, aesthetics can be maintained. Theproduct enables designers to create beautifuledges and faces without the worry of naturalerosion, burrowing animals or carelessgreenkeeping practices from spoiling theeffect. In 2016 and 2017 the true resilience ofthe construction method was tested by themost extreme weather events imaginable. Toconclude this item, who better to commentthan Michael Gonzalez, president ofSecession GC, Beaufort, South Carolina:

“You’ll be pleased to know that ourEcoBunkers at Secession have now survivedhurricanes Matthew (2016) and Irma (2017).Many filled with seawater. Skim the silt, addan inch of sand, a little raking and we’re backin business.”

It is possible to build bunkers that will havea healthier life!