5 - Irrigation
Well planned irrigation systems and processes can support local and statewide water conservation measures.
Irrigation is essential to maintain healthy turfgrass and landscape areas. When rainfall is not enough to sustain healthy playable turf, especially during dry periods, an irrigation system is needed.
Proper irrigation helps provide for optimal course playability, aesthetics, marketability, energy efficiencies, and turf stress reduction. An irrigation management plan can also help extend equipment life, limit repairs, and minimize risks plus supports compliance with local and state regulations. New systems and technologies continue to drive greater efficiencies and controls, while minimizing labor requirements.
Aside from structural BMPs, irrigation practices may reduce administrative management strain, improve employee communications, and reinforce effective training procedures.
Regulatory Considerations
Golf course owners are responsible for contacting federal, state, and local water use authorities at the pre-and post-construction phase to determine annual or specific water consumption, permitting guidelines, and other requirements allowed by regulators
Before an owner begins construction, a water source must be obtained; in the event a new well is to be constructed, in accordance with Sections NR 812.09(4)(a) & (b), Wis. Adm. Code, prior department approval is necessary for the construction or operation of a high capacity well system, with capacity to withdraw more than 100,000 gallons per day, or a well that, together with all other wells on the same property, has a capacity of more than 100,000 gallons per day. Reference for additional information: https://dnr.wisconsin.gov/topic/Wells/HighCap
Water withdrawals must be registered for a water supply system (e.g. well or surface water intake pipe) with the capacity to withdraw 100,000 gallons per day; water use withdrawal includes taking water from surface water or groundwater including springs, ponds, lakes, rivers, streams and the Great Lakes via many different methods for withdrawing water including wells, intake pipes, and ditches
Water withdrawal registration form, plus additional information for permitting, conservation, and efficiency requirements for withdrawals from the Great Lakes Basin and the DNR Waterways Protection Program, including rivers and streams: https://dnr.wisconsin.gov/topic/WaterUse/registration.html
Superintendents have a responsibility to adhere to water-quality and quantity standard rules regarding groundwater and surface water flows resulting from the removal of water for irrigation use
Water samples are required in a variety of situations; this fact sheet outlines applicability for well construction and pump installation to comply with NR 812: https://dnr.wi.gov/files/PDF/pubs/DG/DG0088.pdf
There are several water-management approaches which may be utilized:
Conservation and Efficiency
Conservation and efficiency consider the strategic use of appropriate course and irrigation design, plant selection, computerized and data-integrated scheduling, and alternative water quality/supply options that maximize plant health benefits and reduce the potential for negative impacts on natural resources.
Resource Protection
Resource protection is an integrated approach that includes irrigation practices as part of the course design, pesticide and nutrient practices, and regulatory compliance measures and structural measures as they concern environmental stewardship and policy.
Irrigation BMPs are consistent with the BMP framework developed by GCSAA and incorporating the Wisconsin DNR’s and EPA’s water use guidance:
EPA’s Water Sense - what WI DNR typically references: https://www.epa.gov/watersense
Best Management Practices
Comply with all Federal and Wisconsin laws and regulations
Design and/or maintain a system to meet site’s peak water requirements under normal conditions and be flexible enough to adapt to various water demands and local restrictions
Develop an annual water budget that includes irrigation scheduling for the golf course and maintain accurate records of actual annual water use as compared to the water budget and actual annual evapotranspiration data
Maintain irrigation scheduling that considers periods of maximum ET and energy use.
Demonstrate good stewardship practices by supplementing watering only for the establishment of new planting and new sod, hand watering of critical hot spots, and watering-in of chemicals and fertilizers
(if permissible)Protect aquatic life and impairment of water systems by adhering to state and local water withdrawal allocations (gallons/day)
Design an irrigation system that delivers water with high distribution uniformity (DU) and schedule the system for maximum application efficiency
Identify optimal water source for accessibility, sustainability, water quality, and turf selection; ensure ability to meet seasonal and bulk water allocations for grow-in and routine maintenance
Consult with an irrigation designer to evaluate site and water availability
Pump station should consist of Variable Frequency Drive (VFD) motors, pressure sensors (both high and low), water meters, and leak detection
Consider gravity feed to reduce energy consumption and costs
Utilize a central computer to allow for time adjustments, use weather stations for a baseline, and control costs by using efficiency to run the shortest water cycle with best pressure and distribution
Use the weather station to calculate evapotranspiration (ET) and determine amount of water that needs to be returned to the soil
Conserve water using tools like soil moisture meters, infrared pictures to detect hot spots quicker, hoses, and live feeds of the system via a computer or
smart phoneConsider reduction of manicured turf and conversion to native areas to reduce water use
Separate the landscape into separate program for clubhouse and common areas
Monitor soil moisture and set an acceptable threshold, when below threshold, hand water the specific site
Use mulches in shrubs and flower beds to reduce water evaporation losses
Use drip irrigation in landscape areas to supply water only to plants that need it
Perform daily, weekly, quarterly, and annual inspections of the irrigation system
Choose correct type of irrigation for area requiring water; ranging from full or part circle sprinkler heads to rotor or pop up to drip irrigation
Place meters at wells and pump stations; monitor daily
Irrigation Water Suitability
Water sources should be investigated, and golf course designers and managers should attempt to use alternative supply sources to conserve freshwater drinking supplies, promote plant health, and protect the environment. Sources include potable water, well water, surface water, and reclaimed water. Reclaimed/effluent water use is not commonly used for irrigation in Wisconsin, BMPs have been provided as a reference if applicable.
Potable water: Water suitable for drinking
Well water: Underground water held in the soil and in pervious rock
Surface water: Water from streams, ditches, or diversions
Reclaimed water: Water processed from converting wastewater to a form reused for other purposes such as irrigation
The routine use of potable water supply is not a preferred practice; municipal drinking water should be considered only when there is no alternative. Studies of water supplies are recommended for irrigation systems, as are studies of the waterbodies and flows on, near, and under the property. This information may be useful for the design of stormwater systems and water features of the golf course, in addition to the protection of water resources.
Budget for potential treatment options to address water quality and equipment maintenance as needed.
Additional information on irrigation water suitability:
http://gsr.lib.msu.edu/2000s/2000/000914.pdf
http://plantscience.psu.edu/research/centers/turf/extension/factsheets/water-quality
https://anrcatalog.ucanr.edu/pdf/8009.pdf
Best Management Practices
Irrigation pipeline systems directly connected to municipal water distribution mains must have an approved backflow device at the point of connection
Meter the water supply and maintain accurate records to document irrigation water used monthly and annually; avoid relying on estimated flow data provided by the central irrigation control computers, instead install a totalizing flow meter for accurate record keeping
Monitor the quantity of water withdrawn to avoid aquatic life impairment
Routinely monitor shallow groundwater table of freshwater for contamination of heavy metals and nutrients
Use salt-tolerant varieties of turf and plants to mitigate saline conditions resulting from an alternative water supply or source, if applicable
Reclaimed, effluent, and other non-potable water supply mains must be protected by an approved backflow protection device as specified by state and/or local regulations
Backup/emergency supplies of potable water used to replenish recycled water storage reservoirs must be protected by an approved backflow protection device such as a reduced pressure principle device or an air gap structure as specified by state and/or local regulations
Amend sodic water systems appropriately (with gypsum or an appropriate ion) to minimize sodium buildup in soil
Flush with freshwater or use amending materials regularly to move salts out of root zone and/or pump brackish water to keep salts moving out of the root zone, if applicable
Monitor sodium and bicarbonate buildup in the soil using salinity sensors
Account for the nutrients in effluent water (if applicable) when making fertilizer calculations
Monitor reclaimed water tests regularly for dissolved salt content
Regularly perform soil testing to monitor the accumulation of salts and sodium delivered in the recycled (reclaimed, effluent, or non–potable) water supplies
Where practical, use reverse-osmosis (RO) filtration systems to reduce chlorides (salts) from saline groundwater; if using RO to improve water quality, be certain the reject concentrate (brine) is disposed of in a legal, proper, and environmentally responsible manner
Potable supply lines to buildings (for domestic uses) at recycled (reclaimed, effluent, non-potable) water use sites typically must be protected with backflow prevention device(s) in place, that are operating correctly and tested regularly
Post signage in accordance with local utility and state requirements when reclaimed water is in use
Water Conservation and Efficient Use Planning
Establishing water conservation strategies, alternative sources, and efficiencies can help reduce water consumption and costs. Document watering practices at the golf course to show savings in water use over annual, quarterly, or monthly usage and set goals for continuous improvement. Help align the maintenance team with water conservation goals by regularly and clearly communicating regarding actions which have been implemented, the purpose for those actions, and results. It can be effective to share goals and results with members and the public to support community conservation initiatives. BMP usage and communications are useful for educating the community and public around water use.
If practicable, converting turf in out-of-play areas to naturally adapted native plants, grasses, or ground covers can help reduce the amount of irrigation needed. The best and most effective method to reduce water use on any golf course is to reduce the irrigated acreage where possible.
Best Management Practices
Selecting drought-tolerant varieties of turfgrasses can help maintain an attractive and high-quality playing surface, while minimizing water use
Non-play areas may be planted with drought-resistant native or other well-adapted, noninvasive plants that provide an attractive and low-maintenance landscape
Native plant species are important in providing wildlife with habitat and food sources; after establishment, site-appropriate plants normally require little to no irrigation
The system should be operated to provide only the water that is needed by the plants, or to meet occasional special needs such as salt removal
If properly designed, rain and runoff captured in water hazards and stormwater ponds may provide supplemental water under normal conditions, though backup sources may be needed during severe drought
Always closely monitor soil moisture levels, particularly during a drought; whenever practicable, irrigate at times when the least amount of evaporative loss will occur
Control invasive plants or plants that use excessive water
Existing golf courses can try to convert turf in out-of-play areas to naturally adapted native plants, grasses, or ground covers when feasible to reduce water use and enhance aesthetics
General information on water conservation on golf courses:
United States Golf Association (USGA) Research on Turfgrass Water Use
https://www.usga.org/course-care/water-resource-center/research-on-turfgrass-water-use.html
“Water Conservation” Golf Course Superintendents Association of America (GCSAA)
http://www.gcsaa.org/course/communication/golfcoursefacts/water-conservation
Native vegetation that does not require supplemental irrigation should be retained and enhanced for non-play areas to conserve water where possible.
Irrigation System Design
Courses should use well-designed irrigation systems with precision scheduling for maintained turf areas based on soil infiltration rates, soil water-holding capacity, plant water-use requirements, the depth of the root zone, and the desired level of turfgrass appearance and performance in order to maximize efficient watering. Irrigation is supplemental and is not a replacement of rainfall.
A well-designed irrigation system should operate at peak efficiency to reduce energy, labor, and natural resource use. An irrigation designer and water quality specialist should evaluate the site, water quality mitigation requirements, and water availability. An owner should make the designer aware of details such as plant materials, soils, elevation, expectations, and budget. The designer should produce drawings for the pump station, hydraulics, configure pipe sizing, and determine sprinkler locations based on pre-planning meetings. The water quality specialist will assist in determining any required source balancing delivery system, material requirements, and flushing requirements.
Irrigation managers should be trained to understand soil-water relationships and principles of crop coefficients and ET to prevent applying excess water that percolates beyond the root zone (except when purposely leaching salts). Budget properly for pipe sizing and pump capacity in order to have the shortest and most efficient water-time-window. Sprinkler selection, spacing, configuration (as triangular or rectangular arrangements) and nozzle selections should maximize DU.
Water conservation can also be achieved by separating the landscape into a separate program. Clubhouse and common areas, with correct species selection, can require one to two cycles of irrigation per week compared to four or five cycles for turf. Another option is to use drip irrigation in landscape areas to supply water only to the plants that need it. Utilize reclaimed water when possible. Separate irrigation zones within landscapes, combine plants with similar water requirements (verses watering to the highest water requiring species in a planting) to minimize water usage and pruning requirements
Best Management Practices
Designer should be a qualified irrigation designer/consultant
Designer must approve any design changes before construction
Design should account for optimal distribution efficiency and effective root-zone moisture coverage; target 80% or better DU
Putting surface, slopes, and surrounds should be watered independently; turf and landscape areas should be zoned separately; specific use areas zoned separately: greens, tees, primary roughs, secondary roughs, fairways, native, trees, shrubs, etc.
Incorporate individual sprinkler control instead of “block systems” into design, particularly with fine turf areas
Secure a general irrigation schedule with recommendations and instructions on modifying the schedule for local climatic, soil, and growing conditions as part of the design package; it should include base ET rate for the location
The application rate must not exceed the infiltration rate, ability of the soil to absorb and retain the water applied during any one application; conduct saturated hydraulic conductivity tests periodically; since golf rotors and many other sprinklers’ precipitation rates may exceed soil infiltration rates, avoiding surface runoff is often accomplished by operating sprinklers in short durations with a “soak in time” programmed to occur between each application cycle
Ensure proper operating pressure is included with design – it must not be greater than the available source pressure or a booster pump will be necessary
The design operating pressure must account for peak-use times, maximum flow rates, and supply line size and operating pressures at final buildout for the entire system
The system should be flexible enough to meet peak water requirements and allow for operating modifications to meet seasonal irrigation changes or local restrictions; typically, a system should be designed with at least 15% additional capacity (i.e.; flow rate at the specified operating pressure) to accommodate “catching up” over 7 days if an irrigation event is missed due to a power failure, etc.
Design should account for the need to leach out salt buildup from poor-quality water sources by providing access to freshwater
Underground cables, pipes, and other obstacles must be identified, and their locations flagged prior to construction
Only qualified specialists should install the irrigation system
Construction must be consistent with the design
Construction and materials must meet existing standards and criteria
Permanent irrigation sprinklers and other distribution devices should be spaced according to manufacturer’s recommendations
Sprinklers in turf areas should be spaced for head-to-head coverage
Sprinkler spacing distance should be based on average wind conditions during irrigation
For variable wind directions, triangular spacing is more uniform than square spacing
Distribution devices and pipe sizes should be designed for optimal uniform coverage
The first and last distribution device should have no more than a 10% difference in flow rate; this usually corresponds to about a 20% difference in pressure
Distribution equipment (such as sprinklers, rotors, and micro-irrigation devices) in each zone must have the same precipitation rate
Water supply systems (for example, wells and pipelines) should be designed for varying control devices, rain shutoff devices, and backflow prevention
Water conveyance systems should be designed with thrust blocks (or joint restraints) and air-release valves and/or vacuum release valves as necessary
Sites with significant elevation change may require a design incorporating pressure reducing valve (PRV) station(s) and/or multiple points of connection (POCs), pump stations and/or mainline systems separately pressurized to minimize zones of excess and/or insufficient pressure due to elevation-related pressure loss and/or gain
Flow velocity must be 5 feet per second or less
Pipelines should be designed to provide the system with the appropriate pressure required for maximum irrigation uniformity
Pressure-regulating or compensating equipment must be used where the system pressure exceeds the manufacturer’s recommendations
Equipment with check valves must be used in low areas to prevent low head drainage
Isolation valves should be installed in a manner that allows critical areas to remain functional while making repairs to the system
Manual quick-coupler valves should be installed near greens, tees, and bunkers so these can be hand-watered during severe droughts; consider adding manual quick-coupler valves to areas known to be drier than others
Update multi-row sprinklers with single head control to conserve water and to enhance efficiency
Ensure heads are set at level ground and not on slopes
Non-Play and Landscape Areas
Map environmentally sensitive areas such as sinkholes, wetlands, or flood-prone areas, and identify species classified as endangered or threatened by federal and Wisconsin designation, and state species of special concern. Identify and eliminate invasive species. The most efficient and effective watering method for non-turf landscape is drip or micro-irrigation.
With the help of a golf course architect, golf professional, golf course superintendent, and other key personnel, the amount of functional turfgrass can be evaluated and potentially transitioned into non-play areas requiring minimal, if any, irrigation.
Rain gardens may be installed near roofs and other impervious surfaces to catch and temporarily hold water, helping to provide supplemental irrigation needs for landscape areas.
Best Management Practices
Designate 50% to 70% of non-play area to remain as natural cover according to “right-plant, right-place,” a principle of plant selection that favors limited supplemental irrigation
Incorporate natural vegetation in non-play areas
Consider rain gardens for supplemental irrigation
Use micro-irrigation and low-pressure emitters in non-play areas to supplement irrigation
Routinely inspect non-play irrigation systems for problems related to emitter clogging, filter defects, and overall system functionality
Irrigation Pumping System
Pump stations are critical for water and energy conservation. The pump station needs to be properly maintained and sized to deliver the most efficient use of water and electricity. It should be equipped with control systems that protect distribution piping, provide for emergency shutdown necessitated by line breaks, and allow maximum system scheduling flexibility. Pump stations can also have injection systems for wetting agents, fertilizers, water conditioners, etc.
The pump station should consist of Variable Frequency Drive (VFD) motors, pressure sensors (both high and low), water meters, and leak detection. VFDs can help reduce energy usage to improve conservation and cost reductions.
VFD motors: Regulate water pressure and deliver pump control based on pressure; help reduce energy costs by alternating pump starts and running at lower RPMs based on flow and pressure needed for the system
Pressure Sensors: Provide adjustable sensor pressure to maintain optimal system pressure with current flow; can set high pressure and low-pressure levels for automatic shutdown
Water Meters: Current flow monitored by control unit to optimize energy consumption
Leak Detection: A combination of pressure and water output that can activate shutdown for low pressure
Best Management Practices
The design operating pressure must not be greater than the available pump’s capabilities or source pressure and must account for peak-use times, peak flow rates, and supply-line diameter and operating pressures at final buildout for the entire system
Maintain air-relief and vacuum-breaker valves by using hydraulic-pressure-sustaining values
Install VFD systems to lengthen the life of older pipes and fittings until the golf course can afford a new irrigation system
An irrigation system should have high- and low-pressure sensors that shut down the system in case of breaks and malfunctions
Pumps should be sized to provide adequate flow and pressure
Pumps should be equipped with control systems to protect distribution piping
Check filter operations frequently; an unusual increase in the amount of debris may indicate problems with the water source
Even under routine conditions, keeping filters operating properly prolongs the life of an existing system and reduces pumping costs
Keep records of filter service performed, as this could be an early sign of system corrosion, well problems, or declining irrigation water quality
Document pump motor/equipment run-time hours and monitor pumping station power consumption
Monthly bills should be monitored over time to detect a possible increase in power usage; compare the power used with the amount of water pumped; requiring more power to pump the same amount of water may indicate a problem with the pump motor(s), control valves, or distribution system; quarterly checks of amperage by qualified pump personnel may more accurately indicate increased power usage and thus potential problems
Application/distribution uniformity should be checked annually; conduct a periodic professional irrigation audit at least once every five years; implement a PM program to replace worn components before they waste fertilizer, chemicals, and water
Conduct pump efficiency tests every 1 to 5 years to monitor pump wear, ensure pumps are in good working order, operating efficiently, and not wasting energy
Test frequency should depend on the water quality with 1 to 3-year intervals used if the water is contaminated with sand, silt, clay etc., and longer intervals of 3 to 5 years used with clean or potable water
System checks and routine maintenance on pumps, valves, programs, fittings, and sprinklers should follow the manufacturer’s recommendations
Ensure that all lubrication, overhauls, and other preventive maintenance are completed according to the manufacturer’s schedule
Gravity Feed
Some courses use gravity to supply pressure to the irrigation system. This type of system uses pressure reducing valves (PRV) to regulate pressure as it travels downhill. This design has the reservoir placed at a higher elevation than the highest point of area needing water. The system uses less energy to run, as electrical motors are not needed to supply pressure. There is maintenance required with quarterly upkeep to the PRVs, but compared to energy costs, it is much less.
Irrigation System Scheduling
Irrigation scheduling must take plant water requirements and soil intake capacity into account to prevent excess water use that could lead to leaching and runoff. Plant water needs are determined by ET rates, recent rainfall, recent temperature extremes, and soil moisture. Irrigation should not occur on a calendar-based schedule. An irrigation system should be operated based only on the moisture needs of the turfgrass or to water-in a fertilizer or chemical application, as directed by the label.
Electric/mechanical time clocks cannot automatically adjust for changing ET rates. Frequent adjustment is necessary with these to compensate for the needs of individual turfgrass areas.
An onsite weather station provides the best ET information. A weather station can record sun intensity, temperature, humidity, wind, and rain. It uses data collected to produce a daily ET reading. ET is the process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by the transpiration of plant cells.
If unavailable, follow several local weather stations, such as Weather Underground: www.weatherunderground.com. When using local weather station data, the ET may not be calibrated for turf and the weather station location may not be on turf, so the numbers may not be exactly what is desired. It is possible however to draw conclusions over time in relation to what the turf requirements are.
Best Management Practices
The reliability of older clock-control station timing depends on calibration of the timing devices; this should be done periodically, at least seasonally
An irrigation system should have rain sensors to shut off the system after 0.25 to 0.5 inch of rain is received; computerized systems allow a superintendent to access the control system and cancel the program if it is determined that the course has received adequate rainfall
Install control devices to allow for maximum system scheduling flexibility
Generally, granular fertilizer applications should receive 0.25 inch of irrigation to move particles off the leaves while minimizing runoff
Irrigation quantities should not exceed the available water holding capacity of the soil based on texture and root zone depth
Irrigation schedule should coincide with other cultural practices (for example, the application of nutrients, herbicides, or other chemicals)
Irrigation should occur during hours of the least amount of evapotranspiration
Base plant water needs should be determined by ET rates, recent rainfall, recent temperature extremes, and soil moisture; all driven by site surveying and scouting
Use mowing, verticutting, aeration, nutrition, and other cultural practices to control water loss, maintain infiltration rates, encourage conservation, and increase efficiency
Depending on physical soil characteristics and turf type, using solid-tine aeration equipment in place of verticutting is an option
Slicing and spiking help relieve surface compaction and promote better water penetration and aeration
Visually monitor for localized dry conditions or hot spots to identify poor irrigation efficiency or a failed system device
Use predictive models to estimate soil moisture and the best time to irrigate
Avoid use of a global setting; adjust watering times per head
Base water times on actual site conditions for each head and zone
Adjust irrigation run times based on current local meteorological data
Install rain switches to shut down the irrigation system if enough rain falls in a zone
Use computed daily ET rate to adjust run times to meet the turf’s moisture needs
ET rates should be adjusted by the appropriate crop coefficient (Kc); average Kc values are 0.80 for cool season turfgrasses; Kc values may require minor adjustment through the growing season; average Kc values can be used when creating annual water budgets and/or as a starting point when scheduling for ET replacement
Manually adjust individual control stations’ automated ET data with a Kc to reflect wet and dry microenvironments on the course
Use soil moisture sensors, or if unavailable a soil sampling tube, to assist in scheduling or to create on-demand irrigation schedules
Use multiple soil moisture sensors to reflect soil moisture levels; evaluate variations in soil types across the property using the USDA Web Soil Survey when selecting locations for multiple sensors placement: https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm
Install soil moisture sensors in the root zone for each irrigation zone as feasible to enhance scheduled timer-based run times
Place soil moisture sensors in a representative location within the irrigation zone; installing a soil moisture sensor in the driest or wettest irrigation zone of the irrigation system may lead to over or under watering on a larger scale
Wired soil moisture systems should be installed to prevent damage from aerification
Periodically perform catch-can uniformity tests
Reducing dry spots and soil compaction improves infiltration, reducing water use and runoff
Install emergency shutdown devices to address line breaks
Check to ensure system is operating properly after power outages
Sensor Technology
Irrigation management and control devices need to be installed correctly for proper irrigation management. Soil moisture sensors and other irrigation management tools should be installed at representative locations and depths; and maintained to provide the information necessary for making sound irrigation management decisions. Rain gauges track how much rain has fallen at a specific site on the golf course. More than one station may be necessary to get a complete measure of rainfall or evaporation loss on some courses. Utilization of soil moisture probes and inspections for visual symptoms such as wilting turf, computer models, and tensiometers may supplement these measurements. Computerized displays are available to help visualize the system.
Predictive models based on weather station data and soil types are also available. These are relatively accurate and applicable, especially as long-term predictors of annual turf water requirements. Weather data such as rainfall, air and soil temperature, relative humidity, and wind speed are incorporated into certain model formulas, and soil moisture content is estimated. Note that models rely on data collected and the number of assumptions made for effectiveness and accuracy.
“To prevent excess water use, irrigation scheduling should consider plant water requirements, recent rainfall, recent temperature extremes, and soil water holding characteristics.”
Best Management Practices
Irrigation controllers/timers should be reset as often as practically possible to account for plant growth requirements and local climatic conditions
Properly calibrated flow meters, soil moisture sensors, rain shut-off devices, and/or other automated methods should be used to manage irrigation
Computerized control systems should be installed on new course irrigation systems to help ensure efficient irrigation application; these allow for timing adjustments at every head when systems are designed to provide individual head control
Rain shut-off devices and rain gauges should be placed in open areas to prevent erroneous readings
Ensure that onsite weather stations are properly calibrated and maintained
Pond Location and Design
Lakes and ponds may be used as a source of irrigation water; it is important to consider this when designing and constructing ponds. Careful design may significantly reduce future operating expenses for lake and aquatic plant management.
Best Management Practices
Consult with a qualified golf course architect with stormwater experience, working in conjunction with a stormwater engineer, to develop an effective stormwater management system that complies with the requirements of the DNR
When constructing drainage systems, pay close attention to engineering details such as subsoil preparation, the placement of gravel, slopes, and backfilling
Where practical, internal golf course drains should discharge through pretreatment zones and/or vegetative buffers to help remove nutrients and sediments; carbon filters can be added in cases where vegetative buffers are unavailable
Studies of water supplies are needed for irrigation systems, and studies of waterbodies or flows on, near, and under the property are needed to properly design a course’s stormwater systems and water features, and to protect water resources
Peninsular projections and long, narrow fingers into ponds may prevent water mixing; ponds that are too shallow may reach high temperatures, leading to low oxygen levels and promoting algal growth and excess sedimentation
In shallow or nutrient-impacted ponds, the use of aeration equipment may be required to maintain acceptable dissolved oxygen (DO) levels in the water
Pond Use and Maintenance
Each pond has regions or zones that significantly influence water quality and are crucial in maintaining the ecological balance of the system. It is important to understand their function and how good water quality can be maintained if these zones (riparian zone, littoral zone, limnetic zone, and benthic zone) are properly managed.
Evaporation losses are higher in some regions than others and vary from year to year and within the year. However, evaporative losses could approach six inches per month during the summer. Aquatic plants are more difficult to control in shallow water. Surface water sources can present problems with algal and bacteria growth. Algal cells and organic residues of algae can pass through irrigation system filters and form aggregates that may plug emitters. Use an expert in aquatic management to help develop and monitor pond management programs.
Best Management Practices
Pond leaks should be controlled and managed properly; use leak controls in the form of dike compaction, natural-soil liners, soil additives, commercial liners, drain tile, or other approved methods
Maintain a riparian buffer to filter the nutrients and sediment in runoff
Reduce the frequency of mowing at the lake edge and collect or direct clippings to upland areas
Prevent overthrowing fertilizer into ponds; practice good fertilizer management to reduce nutrient runoff into ponds, which causes algae blooms and ultimately reduces DO levels; use drop spreaders instead of rotary spreaders near these sensitive areas
Establish a special management zone around pond edges
Dispose of grass clippings where runoff will not carry them back to the lake
Encourage clumps of native emergent vegetation at the shoreline
Maintain water flow through lakes, if they are interconnected
Establish wetlands where water enters lakes to slow water flow and trap sediments
Maintain appropriate silt fencing and BMPs on projects upstream to reduce erosion and the resulting sedimentation
Manipulate water levels to prevent low levels that result in warmer temperatures and lowered DO levels
Aerate ponds and dredge or remove sediment before it becomes a problem
A pond should hold surplus storage of at least 10 percent of full storage; in other words, the difference between primary spillway elevation and auxiliary spillway elevation provides 10 percent of pond volume when water level is equal to elevation of the primary spillway
Provide an alternative source for ponds that may require supplemental recharge from another water source such as a well during high-demand periods
Estimated losses from evaporation and seepage should be added to the recommended depth of the pond and if supplied by the irrigation supply, should be included in irrigation water budgets
Metering
Rainfall may vary from location to location on a course; the proper use of rain gauges, rain shut-off devices, flow meters, soil moisture sensors, and/or other irrigation management devices should be incorporated into the site’s irrigation schedule. It is important to measure the amount of water that is delivered through the irrigation system via a water meter or a calibrated flow-measurement device. Knowing flow or volume will help determine how well the irrigation system and schedule are working.
Best Management Practices
Calibrate equipment periodically to compensate for wear in pumps, nozzles, and metering systems
Properly calibrated flow meters, soil moisture sensors, rain shut-off devices, and/or other automated methods should be used to manage irrigation
Flow meters should have a run of pipe that is straight enough — both downstream and upstream — to prevent turbulence and bad readings - consult manufacturers recommendations for the minimum length of straight pipe required in front of the meter
Flow meters can be used to determine how much water is applied over the irrigated area; that can then be converted to inches applied and compared to ET to confirm the average application of water applied as a percentage of ET
Irrigation System Quality
Irrigation system maintenance on a golf course involves four major efforts: calibration or auditing, preventive maintenance (PM), corrective maintenance, and record keeping. Good system management starts with good PM procedures and recordkeeping. Corrective maintenance is simply the act of fixing what is broken. It may be as simple as cleaning a clogged orifice, or as complex as a complete renovation of the irrigation system. Renovating a golf course irrigation system can improve efficiencies, conserve water, improve playability, and lower operating costs.
Best Management Practices
Respond to day-to-day failures in a timely manner, maintain the integrity of the system as designed, and keep good records
System checks and routine maintenance on pumps, valves, control systems, adjustment of programs, fittings, and sprinklers should follow manufacturer’s recommendations
Application/distribution efficiencies should be checked annually. Implement a PM program to replace worn components before they waste fertilizer, chemicals, and water
Conduct a periodic professional irrigation audit at least once every five years
Exercise manual isolation valves annually by closing and reopening to prevent the threads of operating stems from corroding and seizing
Keep valve boxes edged regularly to quickly locate and shut a section of the system off if there is a leak
Annually disassemble, clean and service air and vacuum release valves, PRVs, and any other specialized components included in the design
Gather all the documentation collected as part of the PM program, along with corrective maintenance records for analysis
Correctly identifying problems and costs helps to determine what renovations are appropriate
Maintain written and photo records of pipe or other component failures and repairs; this can become valuable documentation when proposing system renovations and replacements
Sprinkler Maintenance
Maintaining a system is more than just fixing heads. It also includes documenting system and maintenance-related details so that potential problems can be addressed before exhaustive repairs are needed. Establishment of a document indicating what sprinkler configuration is needed for each head in the field as part of an as-built map is recommended to prevent employees from being sent to the field for repairs or audits without the proper information needed, which can cause improper changes to sprinkler heads, leading to inefficiencies. It also provides a basis for evaluating renovation or replacement options. Examples include:
Pipe failures may be caused by material failure or problems with the pump station and/or control system programming resulting in pressure surges and spikes
Wiring problems could be caused by corrosion, rodent damage, insulation nicks, or frequent lightning or power surges
Control tubing problems could result from poor filtration or water supply chemical precipitants such as calcium carbonate
Best Management Practices
The system should be inspected routinely for proper operation by checking computer logs and visually inspecting the pump station, remote controllers, and irrigation heads
A visual inspection should be carried out for leaks, misaligned or inoperable heads, and chronic wet or dry spots, so that adjustments can be made or replaced
Part-circle sprinklers should be checked periodically for proper adjustment; particularly important when irrigating with recycled water so that it does not spray outside of the designated use area
Flush drip/micro-irrigation irrigation lines and filters regularly to minimize emitter clogging; to reduce sediment buildup, make flushing part of a regular maintenance schedule; if fertigating, prevent microbial growth by flushing all fertilizer from lateral lines before shutting down the irrigation system
Clean and maintain filtration equipment
Systems should be observed in operation at least monthly or more frequently if regularly occurring problems dictate otherwise; this can be done during maintenance programs such as fertilizer or chemical applications where irrigation is required, or the heads can be brought on-line for a few seconds and observed for proper operation; this process detects controller or communications failures, stuck or misaligned heads, and clogged or broken nozzles
Monitor and record the amount of water being applied, including system usage and rainfall; by tracking this information, identify areas where minor adjustments can improve performance; this information is essential in identifying necessary renovations and to compute current operating costs for comparison to possible future costs after renovation
Factor in rainfall and compare the total amount of water applied per irrigated acre to ET as a measure of application efficiency
Keep sprinklers edged regularly to ensure proper distribution
Document and periodically review the condition of infrastructure (such as pipes, wires, and fittings); if the system requires frequent repairs, it is necessary to determine why these failures are occurring; for diagnosis of PVC failure causes visit: https://edis.ifas.ufl.edu/ch171
System Maintenance
Routine maintenance helps ensure water quality is maintained and water is used responsibly. System checks include pumps, valves, programs, fittings, and sprinklers. An irrigation system should be calibrated regularly by conducting periodic irrigation audits to check actual water delivery and nozzle efficiency.
Best Management Practices
Irrigation audits should be performed by trained technicians
A visual inspection should first be conducted to identify necessary repairs or corrective actions; it is essential to make repairs before carrying out other levels of evaluation
Pressure, flow, and precipitation rate should be evaluated to determine that the correct nozzles are being used and that the heads are performing according to the manufacturer’s specifications
Check pressure and flow rates at each head to determine average application rate in an area
Conduct catch-can tests on representative areas of the golf course, basic schedule calculations should be executed to determine uniformity of coverage, precipitation rate, and to accurately determine irrigation run times
Conduct internal irrigation audit annually to facilitate a high-quality maintenance and scheduling program for the irrigation system
Inspect for interference with water distribution due to sprinklers below grade, or blockage by tree limbs and/or shrubs
Inspect for broken and misaligned heads
Check that the rain sensor is present and functioning
Inspect the backflow device to determine that it is in place and in good repair
Examine turf quality and plant health for indications of irrigation malfunction or needs for scheduling adjustments
Be aware that early symptoms of root feeding insects may initially be misdiagnosed as droughty areas
Schedule documentation: make adjustments and repairs on items diagnosed during the visual inspection before conducting pressure and flow procedures
PREVENTATIVE MAINTENANCE
In older systems, inspect irrigation pipe and look for fitting breaks caused by surges in the system. For diagnosis of PVC fitting and pipe failure visit: https://edis.ifas.ufl.edu/ch171
Install thrust blocks to support conveyances
The system should be inspected daily for proper operation by checking computer logs and visually inspecting the pump station, remote controllers, and irrigation heads; visually inspect for leaks, misaligned or inoperable heads, and chronic wet or dry spots so adjustments can be made
Maintain air-relief and vacuum-breaker valves
Annually service pressure regulation, pressure relief and/or pressure sustaining valves to assure proper operation
Check filter operations frequently; keeping filters operating properly prolongs the life of an existing system and reduces pumping costs
Application/distribution efficiencies should be checked annually
Conduct a periodic professional irrigation audit at least once every five years
Document equipment run-time hours: ensure that all lubrication, overhauls, and other preventive maintenance are completed according to the manufacturer’s schedule
Monitor power consumption of pump stations for problems with the pump motors, control valves, or distribution system
Qualified pump personnel should perform quarterly checks of amperage to accurately identify increased power usage that indicates potential problems
Increase frequency of routine inspection/calibration of soil moisture sensors that may be operating in high-salinity soils
Winterize irrigation system to prevent damage
CORRECTIVE MAINTENANCE
Replace or repair all broken or worn components before the next scheduled irrigation
Replacement parts should have the same characteristics as the original components
Record keeping is an essential practice; document all corrective actions
SYSTEM RENOVATION
Appropriate golf course renovations can improve system efficiencies, conserve water, improve playability, and lower operating costs
Correctly identify problems and their cost to determine which renovations are appropriate
Determine the age of the system to establish a starting point for renovation
Identify ways to improve system performance by maximizing efficient use of the current system
Routinely document system performance to maximize the effectiveness of the renovation
Evaluate cost of renovation and its return on investment and other benefits including financial, course playability, and turf management (fewer weeds, disease, wet and/or dry spots, etc.)
Irrigation Leak Detection
Irrigation systems are complex systems that should be closely monitored to ensure leaks are quickly detected and corrected. Golf courses without hydraulic pressure-sustaining valves are much more prone to irrigation pipe and fitting breaks because of surges in the system, creating downtime for older systems. If part of the course is moist during dry periods and/or lush vegetation, this could be an indication of a leaking system.
Best Management Practices
Monitor water meters or other measuring devices for unusually high or low readings to detect leaks or other problems in the system; make needed repairs
An irrigation system should have high- and low-pressure sensors that shut down the system in case of breaks and malfunctions
The system should be monitored daily for breaks; log amount of water pumped each day
Document and periodically review the condition of infrastructure (such as pipes, wires, and fittings) - if the system requires frequent repairs, determine why these failures are occurring; pipe failures may be caused not only by material failure, but also by problems with the pump station
Ensure that pump control systems provide for emergency shutdowns caused by line breaks and allow maximum system scheduling flexibility
Programming of central controllers with flow management software must be performed by qualified individuals who understand the relation between pipe size, flow rates, flow velocities and friction loss (of dynamic pressure) so as not to create water hammer or pressure losses by allowing zones to exceed maximum allowable values
Turf Drought Response
Use a soil moisture meter to determine moisture needs of greens and tees. Managers of golf greens cannot afford to wait until symptoms occur. Be prepared for extended drought or restrictions by developing a written drought management plan in consultation with public water suppliers, and applicable local and state agencies.
Best Management Practices
Use soil moisture meters to determine moisture thresholds and plant needs
Irrigating too shallowly encourages shallow rooting, increases soil compaction, and favors pest outbreaks
For golf greens and tees, most roots are in the top several inches of soil, use a soil sampling tube or soil profiler to regularly monitor and determine rooting depths
For fairways and roughs, use infrequent, deep irrigation to supply enough water for plants and to encourage deep rooting
Proper cultural practices such as aeration, mowing height, irrigation frequency and amounts should be employed to promote healthy, deep root development
Create a drought management plan for the facility that identifies steps to be taken to reduce irrigation/water use and protects critical areas, etc.
Use appropriate turfgrass species adapted to the location of the golf course being managed
Collaboration between golf courses, public water suppliers, municipalities, and the DNR is important for drought management and response.
Winterization and Spring Startup
Winterization of the irrigation system is important to protect the system and reduce equipment failures resulting from freezing. Winterizing an irrigation system should occur before temperatures drop below 32° F. It is important to remove as much water from the lines as possible. Many irrigation systems have valves on the low ends that can be opened to drain the lines. This should be completed two to three days prior to connecting an air compressor. The compressed air blow out method is the most common method of draining systems. It clears water out of the pipes, sprinkler control valves, and sprinkler heads. Consult with the manufacturer of the irrigation system components for additional steps regarding winterization.
Best Management Practices
Conduct a visual inspection of the irrigation system: inspect for mainline breaks, low pressure at the pump, and head-to-head spacing
Flush and drain above-ground irrigation system components that could hold water
Remove water from all conveyances and supply and distribution devices that may freeze with compressed air or open drain plugs at the lowest point on the system
Clean filters, screens, and housing; remove drain plug and empty water out of the system
Secure systems and close and lock covers/compartment doors to protect the system from potential acts of vandalism and from animals seeking refuge
Remove drain plug and drain above-ground pump casings
Record metering data before closing the system
Secure or lock irrigation components and electrical boxes
Perform pump and engine servicing/repair before winterizing
Power up the pump station and pump motors at least a couple of weeks before starting to use the system
Recharge the irrigation system in the spring and avoid recharging an empty system with high pressure, keep at a lower pressure (60 PSI or lower) when priming the lines
Each sprinkler should be operated until excess air is flushed from the system; inspect for corrective maintenance issues during spring start up
Ensure proper irrigation system drainage design
Additional information and winterization recommendations may be found at: https://www.usga.org/course-care/regional-updates/central-region/preparing-your-irrigation-system-for-winter.html
Wellhead Protection
Wellhead protection is the establishment of protection zones and safe land-use practices around water supply wells in order to protect aquifers from accidental contamination. It also includes protecting wellheads from physical impacts, keeping them secure, and sampling wells according to the monitoring schedule required by the regulating authority, which may be a local health department and/or the Wisconsin DNR, Bureau of Drinking Water and Groundwater. Licensed water-well contractors may be needed to drill new wells to meet state or local well-construction permit requirements.
When installing new wells, contact the local city regulating authority to determine permitting and construction requirements and the required isolation distances from potential sources of contamination. Locate new wells up-gradient as far as possible from likely pollutant sources, such as petroleum storage tanks, septic tanks, chemical mixing areas, or fertilizer storage facilities.
Best Management Practices
Use backflow-prevention devices at the wellhead, on hoses, and back flow and air gaps to be used at pesticide mix/load station to prevent contamination of the water source
Properly close/plug abandoned or flowing wells
For wellheads located where runoff may contact and/or collect around any part of the wellhead, the area should be graded to include berms to divert surface flow away from the wellhead
Site new wells so that surface water runoff does not contact or collect around any part of the wellhead, including the concrete pad or foundation; or construct a berm near the wellhead that is sufficient to prevent surface water runoff from contacting or collecting around the wellhead
Surround new wells with bollards or a physical barrier to prevent impacts to the wellhead
Inspect wellheads and well casing at least annually for leaks or cracks; make repairs as needed
Conduct a well pump efficiency test every 1 to 5 years to monitor pump and electric motor wear; the frequency of testing should depend on the water quality with 1 or 3-year intervals for water contaminated with sand, silt, clay etc., and every 3 to 5 years for clean water
Maintain records of new well construction and modifications to existing wells
Obtain a copy of the well log for each well to determine local geology and depth; these factors have a bearing on vulnerability to contamination
Sample wells for contaminants according to schedule and protocol required by the DNR
Never apply a fertilizer or pesticide next to a wellhead
Never mix and load pesticides next to a wellhead if not on a pesticide mix/load pad
A good source of tips to protect groundwater is the Groundwater Foundation: www.groundwater.org and https://www.cdpr.ca.gov/docs/emon/grndwtr/wellhead_protection.pdf
Additional information on wellhead protection in Wisconsin:
https://dnr.wisconsin.gov/topic/DrinkingWater/SourceWaterProtection.html
https://dnr.wisconsin.gov/topic/DrinkingWater/wellheadProtection/faq.html
References for licensed well contractors in Wisconsin:
https://dnr.wisconsin.gov/topic/Wells/contacts.html
References for DNR private water supply specialists: https://dnr.wisconsin.gov/topic/Wells/PrivateWaterSupply.html
