The purpose of this article is to discuss several aspects of reclaimed water that are of importance today. Emphasis is placed on water reuse in Florida and California because they are two of the largest producers of reclaimed water in the United
Lawrence R. Parsons, Bahman Sheikh, Robert Holden, and David W. York
Thomas H. Yeager, Joseph K. von Merveldt, and Claudia A. Larsen
The use of reclaimed water as an irrigation source for nursery crops is of increasing importance because many nurseries are located near urban areas that have experienced rapid population growth. Population growth results in increased demand for
Kelly T. Morgan, T. Adair Wheaton, Larry R. Parsons, and William S. Castle
degradation of surface waters by treated effluent water have caused many communities to consider advanced secondary-treated wastewater (reclaimed water) reuse. Currently, there are 440 reclaimed water reuse systems in Florida irrigating 92,345 ha with 2385
Jinghua Fan, George Hochmuth, Jason Kruse, and Jerry Sartain
wastewater is increasingly viewed as a resource for supplying irrigation water and nutrients for landscapes ( Harivandi, 2004 ). Reclaimed water contains nutrients, such as N and P, which are essential plant nutrients. Currently, Florida is a leading user of
Larry R. Parsons*
Florida is one of the larger producers of reclaimed water in the U.S., and use of this water has increased greatly in the past ten years. The objective of this study is to compare changes in reclaimed water use by different entities over the past several years. From 1986 to 2002, total reuse treatment capacity and flow in Florida increased by 221% and 183%, respectively. In the 1980s, reclaimed water was considered to be an urban disposal problem, and cities encouraged use of this water by giving it away for no charge. Because it was free, agricultural irrigation became the largest user of reclaimed water in the mid-1990s and is still one of the larger users. From 1992 to 2002, overall agricultural land area irrigated with reclaimed water increased by 77%. Land area of edible crops irrigated with reclaimed water increased during that period but remained relatively constant around 6070 ha after 1996. Irrigation of other crops increased to 9800 ha. Golf course irrigation increased by 212% to 20,476 ha while residential irrigation increased around 8147% to 33,373 ha during this period. Total flow to ground water recharge and industrial uses increased by 125% and 424%, respectively. While agricultural irrigation is still a large user of this water, other uses such as golf course, residential, groundwater recharge, and industrial are becoming more important. Some cities are no longer willing to provide this water to agriculture for no charge as competition from other entities increases. Agriculture may have to pay for the water, use less water, or develop other water sources.
Michael A. Maurer and Frederick S. Davies
Two field studies conducted from 1990 to 1991 evaluated the effects of reclaimed water on growth and development of 1- and 2-year-old `Redblush' grapefruit (Citrus paradisi Macf.) trees on Swingle citrumelo [Citrus paradisi (L.) Osb. ×Poncirus trifoliata (L.) Raf.] rootstock. Treatments were arranged as a3 (water sources) x 3 (irrigation levels) factorial at two locations on an Arredondo (well drained) and Kanapaha (poorly drained) fine sand near Gainesville, Fla. Irrigation treatments included 1) reclaimed water, 2) reclaimed water plus fertigation, and 3) well water plus fertigation. The reclaimed water was formulated to simulate that of a sewage treatment plant at Vero Beach, Fla. Irrigation was applied at 20% soil moisture depletion, or at 19 or 25 mm·week regardless of rainfall. In both experiments, visual ratings of tree vigor, and measured tree height and trunk diameter, were significantly lower for trees watered with reclaimed water without fertilizer than for the others in both years. Moreover, there was no fourth leaf flush in 1991 with reclaimed water. There was a significant increase in leaf Na, Cl, and B concentrations for the reclaimed water and reclaimed water plus fertigation treatments in 1990; however, in 1991 only leaf B concentrations showed a similar trend. In 1991, there were no significant differences in leaf Cl concentrations. Visual symptoms of N deficiency were observed by the end of the first season in trees grown with reclaimed water. Irrigation levels generallv did not affect tree growth.
Oral Session 2—Water Utilization/Nutrition & Water Management Moderator: Daniel I. Leskovar 18 July 2005, 2:00–3:45 p.m. Room 107
Larry R. Parsons and T. Adair Wheaton
132 ORAL SESSION 41 (Abstr. 306–313) Water Stress–Utilization/Cross-commodity
M.A. Maurer, F.S. Davies, and D.A. Graetz
A field study was conducted on mature `Redblush' grapefruit trees (Citrus paradisi Macf.) on sour orange (Citrus aurantium L.) rootstock from 1991 to 1993 near Vero Beach, Fla. on poorly drained (flatwoods) soil to determine the effects of reclaimed water on leaf, soil and shallow well-water nutrients. Treatments consisted of a canal water applied based on soil moisture depletion, and reclaimed water applied at 23.1, 30.7 and 36.6 mm/wk. Reclaimed water treatments received supplemental fertilization in addition to the N present in the water. All treatments received about 130 kg/ha/yr N. Leaf tissue N, P, K, Ca, Mg and Na concentrations were similar for all treatments, but B concentrations were significantly higher for the reclaimed water treatments in 1991 and 1993. Soil P and Na concentrations also increased in the reclaimed water treatments. Water samples taken from shallow depth wells showed that reclaimed water treatments had lower levels of NO, compared to the control possibly due to leaching. Reclaimed water contained only trace or undetectable levels of heavy metals.
M.A. Maurer and F.S. Davies
Field studies conducted over two growing seasons were designed to study the effects of reclaimed water on the development of 1-and 2-year old `Redblush' grapefruit trees (Citrus paradisi Macf.) on Swingle citrumelo rootstock. Experiments were conducted at two locations on Kanapaha and Arredondo fine sands and treatments were arranged in a 3×3 factorial experiment. Treatments included reclaimed water, well water plus fertigation and reclaimed water plus fertigation, which received <0.023, 0.23 and 0.23kg N/tree/yr in 1990, and <0.034, 0.34 and 0.34kg N/tree/yr in 1991, respectively. In addition irrigation was applied at 20% soil moisture depletion, 1.5 cm/wk and 2.5 cm/wk for 31 weeks in 1990 and 39 weeks in 1991. Tree growth and vigor were greatest for the reclaimed water plus fertigation based on visual ratings and trunk diameter measurements and lowest for reclaimed water alone, where leaves exhibited visual signs of N deficiency. No differences in tree growth or vigor were observed among irrigation rates. Similar results were observed at both experimental locations.