Irrigation System Evaluation

An irrigation system is the most important tool a golf course superintendent has during peak season. If an irrigation system is inefficient and the coverage is poor, it's time to develop a plan to improve its performance. One way of doing that is to create a detailed, logical document that evaluates the entire system.
Pictures, tables, and graphs should be included as evidence along with the good and bad components of the system. For the decision makers who may not know much about irrigation, this sort of information is crucial.
In addition, each section should provide detailed conclusions, recommendations and cost for improvements.
To begin, the evaluator should provide a detailed background of the system.
• When was the irrigation system installed?
• Have there been any improvements?
• What is the equipment currently installed?
• Are there areas that are difficult to operate to specification due to elevation?
A detailed description of the irrigation system background needs to be followed by evaluating the water supply:
• Is there a permit to take water, when does it expire and does it provide enough water?
• Is the water quality: excellent, poor or mediocre?
• Is there an injection system to better manage poor water quality?
• What is the process to find more water and how much is it going to cost?

From the water supply, the heart of an irrigation system, to the pump station needs to be addressed:
• Where is the pump station located and what is the capacity in terms of pressure and flow?
• Is there a pressure maintenance pump?
• Do the pumps loose prime?
• Are there any transfer pumps, where are they located, what is there capacity and how are they controlled?
• How does the pump regulate pressure?
• What type of pump system is used: centrifugal or turbine?
• Does the irrigation system water in an acceptable period or in the water window too long?
• What is the speed of the various pumps?
• Are the pumps serviced annually and are they dependable?

Pump System Controls
• How is the pump system controlled and what is the logic?
• Is it technically up-to-date, is there a flow meter and does anything need to be serviced?
The arteries and veins of the irrigation system (mainlines and laterals) distribute water to each area of the golf course and can severely impact irrigation efficiency and capacity if the pipe was incorrectly sized:
• Are the pipe sizes too small?
• How often do pipes get repaired and are they pipe or fitting repairs?
• Are the fittings thrust blocked?
• What are the types of fittings installed in mainlines and laterals?
• What type predominant type of pipe installed on mainlines and laterals?
• Is there an accurate as-built irrigation diagram?
In combination with pipe size, it's best to also look at the isolation capacity of the irrigation system:
• Are greens and tees isolated on their own?
• Are the fairways looped and can you isolate each fairway or must you isolate large sections of the irrigation system to repair a break?
• What type of isolation valves are throughout the course and are they leaking?
• Are isolation valves accurately mapped on as-built diagrams to quickly locate and isolate a leak?
• Are the valve boxes accessible and do the isolation valves work properly?

After analyzing the isolation valves, the sprinklers need to be assessed on greens, tees, fairways and rough:
• Are the sprinklers correctly spaced?
• Have the sprinklers been strategically placed while considering: soil structure, plant type, micro-climates?
• Are the rotation speeds, pressure and nozzles consistent?
• Are the sprinklers, level, broken or installed on slopes?
• How much labour is spent on hand watering?

Wiring
• What are the various types of wiring installed and have the splices been done properly?
• Is there record of splices and have they been covered by valve boxes and recorded on as-built drawings?
• Are the current power wires and communication wires correctly sized for expansion?

Control Systems
• Is there a central control or is the irrigation scheduled manually?
• What is the condition of the field controllers and are there repairs that need to be made to electrical components or grounding?
• Are the sprinklers operated individually or grouped and is there room to add additional stations?

Management
• What is the level of management required for the irrigation system?
• Is the management intense, fair or adequate?
• Have the schedules been updated on a regular basis?
• Do repairs get done quickly?

In conclusion, an effective evaluation of the irrigation system is a synopsis of it overall condition. It is important that the document is factual and not exaggerated and that each component is in a logical order and easy to follow.

If done properly, the document may serve as a master plan for upgrading an existing irrigation system, or the primary evidence needed to re-design and install a new irrigation system.

Remember, it is not always necessary to conduct a complete evaluation in one season. If money is tight, it might be a better idea to pick away at a few areas each season, proactively improving inefficiencies, and when the time comes to sell major improvements, everything will already be in place!