Citrus Research and Education Center
Lake Alfred, FL33850
Before
1985, many communities in Florida considered sewage wastewater to be a
disposal problem.When it was proposed
to convert wastewater to reclaimed water for crop irrigation, citrus growers
were reluctant to accept the water because of fears of heavy metals, flooding,
or disease problems.For various
reasons, several reclaimed water projects were started, and Water Conserv
II has become one of the largest agricultural irrigation projects of its
type designed for the use of reclaimed water. The project distribution
center is located west of Orlando, FL, and provides irrigation for over
4300 acres of citrus and other crops.Water
is primarily applied to citrus by microsprinkler irrigation.Reclaimed
water is also provided for irrigation of the Orange County National Golf
Center and West Orange Country Club.The
water is chlorinated, is odorless and colorless, and has been used successfully
for crop irrigation for 15 years.Excess
reclaimed water is discharged to areas of rapid percolation called rapid
infiltration basins (RIBs).Water
quality standards were established, and continued intensive sampling insures
water of excellent quality for irrigation.The
reclaimed water meets drinking water standards for a number of compounds
including nitrate, sulfate, Na, Cl, Cu, Zn, Se, and Ag.Initial
fears that reclaimed water would cause flooding, disease, or heavy metal
problems proved to be unfounded.
Tests
were set up to examine effects of different irrigation rates on growth
and production of Hamlin orange and Orlando tangelo on four different rootstocks.Treatments
included annual applications of 16 inches of well water and 16, 50, and
100 inches of reclaimed water.In
the sandy well?drained soil, higher irrigation rates with reclaimed water
promoted better tree growth and fruit yield and caused no major problems.Concentration
of soluble solids in the juice was usually lowered by the highest irrigation
rate, but total soluble solids per acre were 15.5% higher compared to the
16-inch rate, due to the greater fruit production.This
reclaimed water cannot provide complete nutrition, but does supply all
the calcium, phosphorous, and boron required by trees under Florida conditions.Because
of a severe drought in Florida in 2000-2001, attitudes toward reclaimed
water have changed.Once believed
to be a disposal problem, reclaimed water is now considered to be a viable
resource that can meet irrigation demands.From
1992 to 2000, crop acreage irrigated with reclaimed water and average statewide
reuse flow rates increased by 61 and 98%, respectively.