Reclaimed Water Use for Irrigation of Texas Golf Courses

Reclaimed water is proving to be a beneficial source of irrigation water for golf courses around the world. To gain a better perspective of issues associated with reclaimed water use, 487 golf course superintendents in Texas were surveyed over the spring and summer of 2007. Of those, 150 surveys were returned (31% response rate); and 40 respondents (27%) indicated they were using reclaimed water at their facility. Costs and availability were the biggest impediments to reclaimed water use and the most commonly cited problems associated with reclaimed water use were salinity, algae growth, and clogged irrigation heads. Benefits of using reclaimed water included a reliable water source, conservation of fresh water, and costs. Eighty-three percent of superintendents that were using reclaimed water at their facility stated they would continue to use reclaimed water at their facility in the future. Introduction In Texas, rapidly increasing population, regulatory restrictions on ground and surface water usage, and periodic droughts combine to create an ever increasing demand for sources of potable water (12). Golf generates substantial economic activity as a source of outdoor recreation, while also generating a substantial demand on municipal water sources. However, golf courses can also be potential users of reclaimed wastewater thereby mitigating some demand on municipal water supplies. Irrigating with reclaimed water yields more benefits for golf course superintendents than just conservation of fresh water. However, transitioning from potable water use to irrigating with lower quality, recycled wastewater demands changes in both management and regulatory practices (6,7). The purpose of this research was to analyze the inherent benefits and potential problems associated with wastewater reused to irrigate golf courses in Texas. To examine the extent of wastewater reuse on Texas golf courses, a survey questionnaire was drafted and sent to 487 United States Golf Association (USGA) member courses in the state. The Survey Thirty-three questions were selected to be included on the survey (see Appendix 1). These questions were selected after reviewing relevant literature on the topic and also to provide some commonality to a previous survey conducted by Cisar et. al. in Florida (2). Surveys were mailed to course superintendents of 487 USGA member clubs in Texas. Included with the surveys were selfaddressed stamped envelopes to encourage and facilitate the response process. Of the 487 surveys sent, 150 were returned, providing a 31% response rate. Forty responses indicated reclaimed water use and another forty expressed interest in future use of reclaimed water. Descriptive statistics were used to determine commonality of benefits and issues. 19 May 2008 Applied Turfgrass Science Characteristics of Courses Using Reclaimed Water The majority of courses using reclaimed water are private facilities (53%), and the average number of acres being irrigated by those courses is 142 acres. Eleven superintendents reported treated effluent comprised 100% of their irrigation water while treated effluent makes up over 90% of the irrigation water used at eight additional courses. Many courses have been using recycled water for a number of years, with six courses indicating recycled water use for over 25 years, while another 12 have used recycled water for over 15 years. The highest monthly mean use of recycled water is 14,331,586 gal [43.9 acre ft (AF)] and the lowest monthly mean use is 1,148,669 gal (3.5 AF), providing a monthly mean of approximately 7,740,000 gal (23.7 AF) of recycled water per course. The areas most commonly irrigated with recycled water were the primary playing surfaces, including greens, fairways, primary roughs and tees, with each being irrigated by at least 95% of the respondents who used reclaimed water (Fig. 1). Similar use was found in Cisar’s survey (2). Only 37% of courses receive their reclaimed water under adequate pressure to apply to the course, which likely contributes to the fact that 83% of superintendents store the water in open ponds. Open pond storage of reclaimed water is susceptible to algae growth, and this was ranked as the second most important problem by the superintendents (Table 1). Only three courses receive their water under sufficient pressure to not require use of open ponds for storage. Fig. 1. Percentage of courses using recycled water to irrigate specific areas of their course. Table 1. Ranking of potential problems of using recycled water (1 = most important, 5 = least important). Problem / rank 1 2 3 4 5 Salinity 30 4 3 0 0 Algae growth 5 16 6 3 0 Clogged irrigation heads 7 8 10 3 4 Equipment rust 2 1 8 15 5 Complaints from golfers/neighbors 1 2 2 7 19 19 May 2008 Applied Turfgrass Science Costs and Availability Costs and availability are major considerations when deciding to use reclaimed water, and may be the determining factor on the feasibility of reclaimed water use (6). The main impediment to reclaimed water use appears to be irrigation system construction and retrofit costs, as well as availability (3,5). This concern was present in the survey responses as costs and availability were the most frequently cited reasons for not using reclaimed water. It has been shown to be more costly to retrofit a course after construction than to install a dual distribution system during course construction (6). In many locations, recycled wastewater has been priced to competitively compete with tertiary treated potable municipal water. Many places have adopted a philosophy that reclaimed water should be priced at 80% of potable water prices (4,9). Similar to the Cisar et al. survey (2), we found that 48% of the respondents do not pay for the recycled water they receive. Twenty-five percent reported a monthly fee, and another 18% pay a flat fee. Of those who do pay for their water, costs range from $1,000 to $200,000 annually, with a median price of approximately $50,000. Water Quality and Management Considerations The federal government does not identify specific parameters for wastewater reuse (although the EPA provides Guidelines for Reuse); therefore the regulatory power is extended to individual states. The Texas Commission on Environmental Quality (TCEQ) regulates water quality for reuse application in Texas. Water quality parameters regulated by the TCEQ are Biochemical Oxygen Demand (BOD5)or Carbonaceous Biochemical Oxygen Demand (CBOD5) turbidity, and fecal coliform levels (11). This means that individual courses should monitor and perform chemical analysis of the water they receive. Thirteen percent of the superintendents receive detailed chemical analysis from their reclaimed water provider, and another 23% noted that an analysis is available by request. Eighty percent of the superintendents obtain their own water quality analysis. Salinity, sodium/sodium absorption ratio (SAR) and pH are the most commonly monitored water quality parameters, but boron, chlorine, chloride, bicarbonates, carbonates, nitrogen, phosphorous, potassium, and suspended solids are all monitored by a significant proportion of the superintendents (Fig. 2). As expected from review of the relevant literature, salinity was identified as the most important problem associated with using recycled water, followed by algae growth, clogged irrigation heads and equipment rust (Table 1). Another important statistic, which was also found by Cisar et al. (2), is that complaints from golfers and neighbors were considered the least important problem associated with recycled water use. 19 May 2008 Applied Turfgrass Science Fig. 2. Number of respondents monitoring particular water quality parameters in their recycled water. Increased levels of some constituents in reclaimed water pose significant risks to soils and turfgrasses, creating "degradation of aggregate stability, a decrease in the soil hydraulic conductivity, surface sealing, runoff and soil erosion problems, soil compaction and a decrease in soil aeration" (8). While many constituents in reclaimed water can have a detrimental effect on turfgrass growth, some nutrients can have positive effects on soils and turfgrass (7). The increased nutrient load in reclaimed water can be used efficiently by the turfgrass, having a substantial economic value by reducing the amount of fertilizer needed to maintain the aesthetics and playability of the course (7). Water and fertilizer savings were cited as the second most common management issue when using recycled water. The need to periodically leach soils was at the top of the management issues most important to superintendents (53%); equipment deterioration was also considered significant by 23% of the superintendents. Several of the respondents (35%) acknowledged that they were limited in the time they could irrigate with reclaimed water, typically at night when there are no golfers present. The employment of low water use grasses and plants is another management practice adopted on thirtyone of the courses. The survey responses noted in this section are evidence of the increased management issues that accompany the use of reclaimed water for irrigation. Increased management issues also bring with it increased benefits. Superintendents were asked to rank the potential benefits of using recycled water based on their experience using a Likert scale (with one ranking most important and three least important). Guaranteed water supply received the best ranking, followed by conservation of fresh water and finally overall cost savings. Respondents displayed an overall satisfaction with using recycled water. Again employing a Likert scale rating system (one indicating high satisfaction and five indicating high dissatisfaction), 27 respondents were either satisfied or highly satisfied with their reclaimed water experience, while only two responses indicated dissatisfaction or high dissatisfaction and 83% of the golf course superinten