Considerations in Retrofitting a Golf Course - USGA Green Section ...

Considerations inRetrofitting a Golf Coursefor Recycled Water IrrigationStart thinking about preparing for the use of recycled water at your course.BY M. ALl HARIVANDIWithin the United States aswell as the rest of theworld, the future of thegolf industry is tied to water availabilityand price. Even in areas where waterwas once an unlimited resource, it isnow viewed as limited and higWyvaluable, particularly in arid, semi-arid,and higWy populated regions. The priceof potable water rises with scarcity;both rising cost and the increasedpoliticization of using a scarce resourcefor leisure and entertainment purposesput pressure on golf courses to usesomething other than potable waterfor irrigation.In many locations, using recycledwater (i.e., treated municipal sewagewater, which may also be known asreclaimed or effluent water) for golfcourse irrigation is a viable strategy forcoping with water shortages and therising cost of fresh water. Some states, infact, have already mandated recycledwater irrigation on new golf coursesand landscapes. Elsewhere, interest inrecycled water irrigation continues toincrease as more and better-qualityrecycled water becomes availablefor re-use.Irrigating a golf course with recycledwater poses unique challenges for acourse superintendent. Whether acourse is new and in the developmentphase or well established and switchingto recycled water irrigation, issues arisein the areas of environmental stewardship,health, and agronomics. Theseissues are more easily addressed when a30 G R E ENS E C T ION R E COR 0 .

course can be designed and built withrecycled water irrigation in mind thanwhen an established course decides toretrofit (or convert) to recycled wateruse. In both instances, however, a numberof concerns are best handled duringthe planning phase; in fact, preparingfor recycled water irrigation is almostalways more efficient and effective thanmanaging the potential negative effectsof its misuse.Resolution of the following infrastructureand management issues willensure minimal negative impact ofrecycled water irrigation on the playabilityand agronomic health of a golfcourse. It will also ensure that legal andfinancial responsibilities are carefullyconsidered and all parties are clear ontheir roles and responsibilities shouldproblems arise. Most of these issuesapply equally to courses under developmentand those being retrofitted forrecycled water irrigation. Every site,however, will also be subject to specifichealth and environmental regulationswhich, due to the great variationbetween sites and communities, are notdiscussed here. Readers are thereforeadvised that the following discussion isnot exhaustive with respect to suchissues, complete evaluation of whichshould occur before contractssigned.RECYCLED WATERTREATMENT PROCESSRecycled water used for golf courseirrigation must be at least secondary,and preferably tertiary, treated wastewater.Secondary treatment is a biologicalprocess in which complexorganic matter is broken down to lesscomplex organic material, then metabolizedby simple organisms that arelater removed from the wastewater.Secondary treatment can remove morethan 90 percent of the organic matterin sewage. The secondary liquid effiuentis always chlorinatedareor otherwisedisinfected before release. Often, sewagetreatment facilities associated with residentialdevelopments consist of aeratedlagoons, a less sophisticatedsecondarytreatment process.Advanced wastewater treatment consistsof processes similar to potable watertreatment, such as chemical coagulationand flocculation, sedimentation, filtration,or adsorption of compounds by abed of activated charcoal. Becauseadvanced treatment usually followshigh-rate secondary treatments, it is"""-,- ,:.; '",".- ..sometimes referred to as tertiary treatment.These processes can providehighly purified waters. Reverse osmosis,an advanced method of water treatment,can actually produce pure water;however, very high initial and operationalcosts and environmental problemsrelated to disposal of reject salinebrine limits the use of this process forgolf course irrigation.Generally, secondary and tertiarytreated waters do not differ significantlychemically - i.e., in their dissolved saltcontent. However, due to the greatlyreduced level of suspended (i.e., notdissolved) solids, tertiary waters aremuch more desirable for golf courseirrigation. Suspended solids can plugirrigation heads and seal sand-based(USGA or California type) golf greens,thereby reducing drainage. Consequently,installing an efficient filtrationsystem is essential whenusing recycledwater for golf course irrigation, especiallyif the recycled water is onlysecondary treated effiuent.AGRONOMIC ANDMANAGEMENTCONSIDERATIONSFOR RETROFITThere are unique challenges associatedwith using recycled water to irrigategolf courses originally designed forfreshwater irrigation. Depending on thequality of the recycled water available,the costs of converting an irrigationThe issue of water availability system andcontinues to grow and impacts all adapting courseindustries.With rising costs of maintenance to thepotable water, the use of new irrigation canrecycled water is a viablebe substantial. Thestrategy. Once thewater arrives at thetreatment facility.itmust receive at leastsecondary, andpreferably tertiary,treatment before itcan be used onthe golf course.cost and managementfollowing items allbear carefulconsideration inplanning forconversion of acourse to recycledwater irrigation.Most, have bothconsequences,although some are cost free. Some ofthe items may have already beenaddressed by local authorities - e.g.,regulatory issues. Every effort is madeto include all items of potentialconcern in this report; however, other,site-specific issues that are not apparentinitially may come to light as theconversionproject progresses.IRRIGATION SYSTEM ISSUES• Cross connection. Protection ofcross-connection systems may benecessary if the golf course irrigationsystem is connected to a potable watersystem or any dedicated fire line usingpotable water. In general, all physicalconnections between the recycledwater irrigation system and the potablewater system must be disconnected.• Lakes, wells, and creek protection.On-site lakes, wells, and creekswhose water is used for potable purposesshould be protected from oversprayor runoff from recycled waterirrigation. Drinking-water fountains onthe property should also be protectedfrom overspray. Local regulations mayrequire modification or redesign of theN ov EMBE R.- D E CE MBER. 2004 31

irrigationsystem to ensure theseprotections .• Quick couplers. It may be necessaryto tag or replace all quick couplerson the course with specialized couplersthat prevent inadvertent drinking ofrecycled water by maintenancepersonnel or others.• Labeling, tagging, and painting.On new golf courses, purple irrigationsystem components generally signify(and warn unsuspecting users of) thepresence of recycled water. On existinggolf courses, all buried components ofthe existing irrigation system are often"grandfathered in." However, a golfcourse may be required to label allvisible irrigation system componentswith purple tape, tags, paints, etc. It mayalso be necessary to install signs warningof recycled water use in more than justEnglish (in most cases, warnings inSpanish are also mandatory) throughoutthe course, at the clubhouse and proshop, and on scorecards. The cost of this"publicity" will depend on the typeand magnitude of labeling a coursechooses.• Pumping costs. Depending on thepumping capacity and pressure requirementsof the existing system, a boosterpump and electricity for additionalpumping may be required. The pressureprovided by the treatment plant releasingthe recycled water is often inadequatefor irrigating a golf course.• Water storage facilities -construction and maintenance.If recycled water cannot be stored inexisting lakes on the course, additionalstorage facilities may be required.Covered storage tanks or "lined" pondsare options. The size and location ofsuch storage facilities must be thorougWyevaluated in relation to environmentalissues as well as for both fIxed andoperational costs. Note: Recycled waterstorage facilities require a high level ofmaintenance. Generally, covered (orburied) storage tanks require less maintenancethan lakes, since the absence oflight eliminates algae growth; on theother hand, settling of suspendedmatteris a problem in tanks. With frequencydepending on water quality, storagetanks must be periodically emptied andcleaned. The initial cost of constructinglined storage lakes may be less than thatof installing covered tanks; however, themaintenance cost is generally higher.Due to elevated levels of nutrients suchas nitrogen and phosphorus, algae andweed growth is a constant problem instorage lakes. Substantial labor andchemicals are often needed to keeppond water clean and suitable for irri-It is commonplace that purple irrigation systemcomponents generally signify and warn unsuspectingusers of the presence of recycled water.gation. Depending on the quality of thewater, the cost of maintaining a storagepond for recycled water could beseveral times higher than maintenancecosts for a pond of potable water (dueprimarily to algae and weed growth,and odor problems). If any existing lakeat a course is converted for storage ofrecycled water, it may require lining toprevent potential groundwatercontamination.• Irrigation water filtration. Giventhe suspended matter content ofrecycled water, a dependable irrigationfiltration system may be essential.Particularly if recycled water is stored inponds, where algal bloom is a constantproblem, filtration must be of highquality. If the existing filter system at acourse is sub par, it must be replacedbefore beginningrecycled water irrigation.Without effective filtration, algaeand other suspended matter will plugirrigation nozzles, reducing irrigationefficiency and uniformity, and requiringadditional labor for repeatedly unpluggingheads. In addition, without adequatefiltration, the fIne, suspendedparticles delivered in recycled watermay plug pore spaces in the rootzoneof sand-based golf greens, impedingboth drainage and leaching - costlyproblems!• Irrigation water blending. Recycledwater may need to be blendedwith fresh water to reduce its salt content.If blending, often done in a storagetank or lake, is not possible, a coursemay be alternately irrigated with recycledand fresh water to leach salts (aprocess called "flushing"). Cost andlogistics would determine whichapproach is used at a given golf course.• Adjacent properties. Dependingon local regulations, golf courses irrigatedwith recycled water may berequired to protect adjacent propertiesfrom runoff or overspray from theirirrigation. Compliance with such regulationsmay mean redesigning the irrigationsystem to allow irrigation of theperimeter with fresh water.AGRONOMIC ISSUES• Recycled water dissolved salts. Inmost cases, recycled water will have ahigher dissolved salt content than thewater already being used for irrigation.In addition to salinity, other importantchemical components of the recycledwater are pH, sodium, calcium, magnesium,cWoride, boron, bicarbonate,and residual cWorine. Depending onthe levels of these chemical constituents,management practices on the coursemay need to change to counteractpotential negative effects on soil, turfgrasses,and other plants. Such effectsmay range from slight to substantial.Without an analysis of the recycledwater, it is impossible to predict theextent of its effect on management;however, any or all of the followingmay be needed:1. Irrigation water blending (i.e.,recycled with fresh).2. Injection into the irrigation waterof acids, gypsum, or other amendments.32 GREEN SECTION RECORD

3. Application of gypsum, sulfur, andother amendments to the soil.4. Additional core aerating to reducesoil impermeabilitysodium levels.caused by elevated5. Installation of additional drainagelines in low-lying areas to removeleached salts.6. Application of additional herbicidesand fungicides to combat weedand disease problems if existing grassesare stressed by the presence of salt.7.Application of more water than iscurrently applied to leach salt below thegrass rootzone (leaching requirement).8. Regular and more frequent soil andwater testing. Twice a year, soils must belab tested to identify potential salinityproblems. Soil samples should be takenfrom representative greens, tees, fairways,roughs, and general landscapedareas. Recycled water must be lab testedat least quarterly to determine the leveland fluctuation of dissolved salts.• Trees, shrubs, and other non-turfplants. Depending on the recycledwater's salt content as well as the sensitivityof the course's trees, shrubs, andother plants, remedial actions may berequired to prevent plant injury. Themost common remedial practice ismodification of the irrigation system sothat water from sprinklers does not wetplant leaves. Although trees and shrubsmay tolerate certain levels of saltaccumulation in the soil, they canexhibit injury from saline water sprayedon their foliage.• Consultant fees. Agronomic issuesrelating to recycled water can be complex,requiring the input of consultingspecialists. Most golf course superintendentswork closely with a turfgrass waterquality consultant. The cost of such service,as well as lab test fees, is a consistentrecurring cost associated with recycledwater irrigation, and it should be addedto the management budget.ENVIRONMENTAL ANDMANAGEMENT ISSUES• Groundwater monitoring. If agolf course is locatedabove a drinkingwater aquifer, a comprehensive groundwaterquality monitoring program maybe required if the course is irrigatedwith recycled water. At issue is whetherthe golf course or the sewage treatmentplant is responsible for mounting andpaying for such a program.• Odor problems. Depending on thelevel of treatment, recycled water irrigationmay cause an odor problem.It should be decided in advance whowill be responsible for correcting thesituation .This specialdesignprotectsthe waterfountainfromstruckrecycled" irrigationwater.being• Liability issues. Although extremelyrare, human health problems, adjacentproperty contamination, and othernegative impacts may result fromrecycled water irrigation. It is highlyadvisable to determine ahead of timewhetherbythe golf course or the sewagetreatment plant, or both, will takeresponsibility for such outcomes.• Equipment deterioration. Turfgrassmaintenance equipment rusts anddeteriorates in other ways more quicklywhen exposed to saline irrigationwater. How big a problem this may beat a given golf course will depend onthe salinity of the recycled water.• Golf course superintendentcompensation. Switching from freshto recycled irrigation water will add tothe responsibilities (and therefore onthe-jobtime) of the golf course superintendent.In addition to extra agronomictasks that the use of recycledwater imposes, the superintendent willspend more time inspecting,keepingrecords, preparing reports, and filingdocuments with environmental andregulatory agencies. He will also haveto spend more time with regulators,community representatives, consultants,laboratories, and vendors providinggoods or services related to recycledwater. Total labor needs on the course,including that of the superintendent,often rise 10-20% when recycled waterirrigation replaces freshwater irrigation,the actual figure depending on thequality of water used.ADVANTAGES OFRECYCLED WATER• Conservation and availability.Using recycled water is an excellentmeans of conserving fresh water. Wateravailability, especially during a droughtor other water shortages, is almostguaranteed when using recycled water.• Cost. Recycled water is almostalways less expensive for golf courseirrigation than fresh water.• Nutrient Content. All recycledwaters contain nutrients required byturf plants (e.g., nitrogen, phosphorus,and potassium). The quantities of nutrientsavailable at a given site and theirimpact can only be evaluated afterrecycled water becomes available andcan be tested for nutrient content. Thislimitation notwithstanding, most recycledwaters contain enough nutrientsto completely eliminate fertilization ofroughs and even fairways, and to substantiallyreduce the fertilizer requiredby greens and tees.AUTHOR'SNOTEUse of recycled water for irrigation is rapidlyspreading worldwide. The author is interested instaying abreast of issues arising from recycledwater irrigation on golf courses in regions withvarying social, environmental, political, andclimatic conditions. Readers are encouraged tocommunicate issues related to recycled waterirrigation that are not covered in this article. Theauthor will compile and periodically cover theseissues in new publications. The author may bereached at: maharivandi@ucdavis.edu.M.A.u HAI,uVANDI, PH.D., is an environmentalhorticulturistfor the University ifCalifornia Cooperative Extension in theSan FranciscoBay Area. He also is amember if the USGA Tu1fgrassandEnvironmental Research Committee.NOVEMBER-DECEMBER 2004 33