A close look at the economic benefits of water research
Widespread droughts and other environmental concerns in the 1970s drove the decision to invigorate United States Golf Association (USGA) turfgrass research in 1982 (6). Since then, the USGA has invested more than $45 million in turfgrass and environmental research, which, among other things, has improved irrigation efficiency on U.S. golf courses.
The effort to estimate rates of evapotranspiration (ET) for the turfgrasses used on golf courses was an essential first step in water conservation (5). Fixed and mobile soil moisture sensors are another important innovation in irrigation management, which now are commonly used by golf course superintendents to estimate irrigation thresholds as soils dry. Scientists used nascent versions of these devices in early turfgrass water-use research supported by the USGA, and Green Section staff have helped normalize commercial TDRs in irrigation scheduling (1,7).
However, the economic benefits of these water conservation strategies are unknown. Therefore, our objective was to estimate the golf industry’s resource use and financial benefits from the USGA’s investment in ET-based irrigation (ET) and soil moisture sensing (moisture meter, MM) strategies.
Survey
We partnered with Fleishman-Hillard’s TRUE Global Intelligence research division to survey superintendents with an online instrument focused on the benefits associated with golf-facility adoption of research-based management practices in six primary areas of interest. These include 1) ET-based irrigation scheduling (i.e., ET or water budgeting), 2) soil moisture sensing (i.e., MM), 3) BMPs that reduce nonpoint source pollution of fertilizers and pesticides, 4) putting green construction techniques, 5) naturalized rough and 6) improved turfgrass cultivars. For this article, we will focus on ET and MM.
We sampled the Golf Course Superintendents Association of America’s (GCSAA) superintendent research panel and supplemented outreach with the GCSAA’s superintendent database. We closed the survey in August 2020 with 610 complete responses from the U.S. and Canada (2 percent of responses).
The survey had sections to profile facilities and collect relevant adoption and economic benefits data for ET and MM. We asked about familiarity with ET and MM, if the course adopted either ET or MM, the extent of perceived benefit(s) associated with adoption and the timing of adoption. We asked respondents that had not adopted a strategy whether and when they plan to adopt one.
Modeling
We developed three econometric models for ET and MM from survey data:
(1) a logit (i.e., yes/no) model to predict the probability of familiarity,
(2) a logit (i.e., yes/no) model to predict the probability of previous adoption, and
(3) a multiple regression model to estimate the average annual monetary cost-savings for an adopting facility.
We only asked facilities that were highly familiar (i.e., at least a score of 3 on a 1-4 scale) with a management practice about their experience with adoption. We used each to score the entire sample of 610 respondents. The base prediction — labeled model (mean) in Figures 1 and 2 — was the average prediction across all scored respondents.
In addition, we provided alternative predictions with the upper and lower quartiles to estimate statistical uncertainty. We projected aggregate savings estimates from these predictions and industry-population data for each management practice. We provide a model projection for each strategy for annual savings (in percent and USD) per facility basis and projections for the total number of adopting facilities and total (industry-wide) savings (million [M] USD).
Participant profile and awareness
Golf course superintendents comprised 95 percent of the respondents. Member-owned facilities were most prominent among survey respondents (slightly more than one-third). Approximately 70 percent of respondents had maintenance budgets less than $1 million annually, and 22 percent had budgets between $1 million and $2 million.
There was a good geographic spread across the U.S. Nearly 75 percent of the facilities had 18 holes, and 20 percent were larger. Approximately 40 percent of the facilities ranged between 99 and 150 acres, and the remaining 60 percent were split nearly equally between smaller and larger facilities. Approximately 55 percent of the facilities used less than an acre-foot of water per acre (325,851 gallons per acre) annually; only 10 percent used four acre-feet per acre (1.3 million gallons per acre) or more annually. In addition, approximately one-third of all facilities irrigated less area in 2019 than in the previous year.
Approximately 90 percent of respondents were familiar with ET and MM, but the rate of adoption was more variable — 0 percent for ET and 50 percent for MM (Table 1).
Savings reported
Adopters of MM reported higher annual cost savings per facility than adopters of ET (Table 2). ET-based irrigation had the highest proportion of the earliest adopters, with approximately 30 percent reporting adoption more than 10 years ago (Table 3). Conversely, only 8 percent of MM adopters did so more than 10 years ago. Planned adoption timing was very similar among the two strategies, likely reflecting the uncertainty of future behavior (Table 4). For brevity, we did not include coefficients from logit and regression models in this summary. These are available in the original paper.
Factors driving familiarity and adoption
To summarize, the models reflect the size of the maintenance budget was an important driver of familiarity, especially for MM. Social media users also were more likely to be familiar with ET and MM. The maintenance budget and (to a lesser extent) the size of the facility affected the adoption decision for ET and MM. Unsurprisingly, facilities in the West were much more likely to have adopted ET than those in the Northeast.
Projected average facility cost savings
For each adopting facility, we calculated annual monetary cost-savings generated for each intervention from responses to seven cost-savings questions from the survey — one each for water use, potable water use, labor, fuel, fertilizer, pesticide and general cost savings related to more efficient turf management. Total cost-savings (e.g., the sum over these seven individual categories) was the dependent variable explained in the cost-savings regressions.
Modeling indicated that U.S. golf courses save between 4 and 6.7 percent in annual maintenance expenditures for ET and MM,respectively (Figure 1A). Using self-reported maintenance budgets from the survey and national maintenance budget estimates, we can easily map the percent savings from percentages to USD (3). With this detail, we estimated that the average adopter of ET saves approximately $37,000 annually, whereas MM saves adopting facilities $62,800 annually (Figure 1B). It is important to note that adopters attributed roughly 57.5 and 71 percent of the savings from ET and MM, respectively, to labor efficiency. Water use attributed to the second-largest portion of savings for these strategies (25.7 percent for ET and 18.1 percent for MM).
These savings are relatable and have contributed to water conservation on golf courses reported by others (2). Surveyed superintendents showed a 21.8 percent decrease in annual water use from 2005 to 2013. A small part of this reduction was from golf course closures but conservation practices (e.g., keeping turf drier and using irrigation management techniques, etc.) and voluntary removal of acreage accounted for most of the reduction.
Projected industry-wide adoption and savings
We estimate approximately 7,683 facilities to adopt MM, whereas only 4,522 facilities adopted ET (Figure 2A). We estimated industry-wide savings for the U.S. golf industry with adoption and annual USD savings projections from the per-facility models. Soil moisture meters represent the greatest industry-wide savings ($529.5 million annually), driven by higher annual savings per facility and more adopting facilities (Figure 2B).
Conclusion
Widely-adopted ET scheduling and MM save the U.S. golf industry an estimated $730 million yearly. This compares to an estimated yearly Green Section budget of roughly $10 million, which invests about $2 million in turfgrass and environmental research.
Research investments are critical to the sustainability of the golf industry. Government and industry leaders should note the return on investment and other metrics documenting these benefits and increase turfgrass and environmental research investment.
Cole S. Thompson, Ph.D., research director, USGA Green Sectionl; Donald J. Kridel, Ph.D., department of economics, University of Missouri-St. Louis; and Michael P. Kenna, Ph.D., retired, USGA Green Section. For more information, contact Thompson at cthompson@usga.org.
The article summarizes a portion of Thompson CS, Kridel DJ, Kenna MP. Economic and sustainability benefits of the United States Golf Association’s investment in water, fertilizer, and pesticide management research. Int Turfgrass Soc Res J, 2022;1–11. https://doi.org/10.1002/its2.91
Acknowledgments
The United States Golf Association funded this research. The Turfgrass and Environmental Research Committee, the countless scientists that have measured the intersection of turfgrasses and the environment, the USGA Executive Committee and senior leaders and myriad staff of the Green Section, made the extolled benefits of the research herein possible. We appreciate the significant contributions of Kim Funcik and Eric Rydell with FleishmanHillard TRUE Global Intelligence for their excellent work with survey implementation. Thanks to the Golf Course Superintendents Association of America for assistance with survey distribution.
References
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