This is part three of a six-part series on golf course water use. Read Part 2.
When it comes to irrigation, the term “management” refers to the gathering and assessing of information to make an informed decision. A good starting point for developing your water management plan is by describing how water management decisions are made at your golf course. Is it a best guess based on how the golf course looks on any given day, or a reaction to comments from golfers? What specific factors go into when, where and how much water is applied to the golf course?
Water requirements vary throughout a golf course based on sun and shade patterns, slope, soil differences and other such factors, and the irrigation management plan must take those factors into account. A good source of baseline information that superintendents use to estimate turfgrass water requirements is reference evapotranspiration (ETo). Superintendents know by experience that some areas of the course tend to dry out faster and some remain wet longer even though the same amount of water was applied to both areas. These areas require constant monitoring and adjustment to supply just the right amount of water.
A recommended part of the written water management plan is developing a water budget for your golf course. This is an exercise that compares estimated water use based on historical ET to actual water use. Although annual water use varies based on weather conditions in any given year, historical water use does not vary as much as one might think. A water budget is a useful tool to measure and manage how much water has been applied to the golf course while providing a benchmark for future improvements. The article How to Develop a Water Budget for Your Golf Course (USGA) provides step by step instructions on developing a water budget.
Another essential aspect of the irrigation management plan is having the plan in writing so that it becomes a vital part of your overall golf course maintenance plan. A written plan can be shared and discussed with others and adjusted if necessary. If it is not written down, it doesn’t exist.