Water Recycling, Reclaiming and Reuse
With a growing population, running out of water is a big concern. Wells are constantly being placed for new homes which are causing springs, aquifers, streams and lakes to go dry. How can we help to conserve water? Water reclaiming is a great way to preserve all of these things. Reclaimed water is water from municipal wastewater treatment plants that has been treated to levels that allow safe use for designated purposes. “Water reuse” is the term used to describe the application of reclaimed water for beneficial purposes.
Approximately 727 million gallons of reclaimed water is used every day in Florida, which makes it the leader in the use of reclaimed water use. Encouraging and promoting reuse in Florida is a state objective for conserving freshwater supplies.
Why Reuse Water?
Reusing water has several environmental benefits. Currently a large percentage (40-60%) of potable water (drinking quality water) is used for non-potable needs such as landscape irrigation. Conservation measures such as irrigating with reclaimed water is one way to reduce the use of existing potable water supplies.
- Reduces groundwater withdrawals
- Reduces the need for new drinking water supplies such as new surface water withdrawals or desalination plants
- Reduces the need for new drinking water infrastructure such as storage reservoirs, pipelines and water treatment plants
- Improves water quality of the natural environment by reducing the amount of nutrients that are discharged directly to surface and groundwaters
Reusing water helps conserve drinking water supplies by replacing the use of drinking quality water supplies by replacing the use of drinking quality water for non-drinking water purposes. The idea behind water reuse is simple: use the right water for the right use. Reusing water helps reduce environmental degradation of lakes rivers, streams, and coastal waters. Thus, reducing the amount of nutrients that are directly discharged to natural systems, which has been the traditional wastewater disposal method.
Landscape irrigation with reclaimed water must be managed carefully to reduce the potential for eutrophication of water bodies. Traditionally viewed as a waste to be disposed of, reclaimed water is now viewed as a valuable resource by conserving water as well as for the supply of nutrients it contains.
Reclaimed Water Use in Florida
In Florida, reclaimed water is used in a variety of ways with the largest amount used for irrigating public access areas such as golf courses, athletic fields, parks, etc. The next largest uses are groundwater recharge and industrial uses such as cooling water in power plants. Most of the reclaimed water used for agricultural irrigation is used to grow feed, fiber, or other crops that are not for direct human consumption. However, reclaimed water can be used to grow crops for human consumption in Florida if stringent treatment and disinfection requirements for public access area use are met. Also, reclaimed water is not allowed to come in direct contact with crops that will not be peeled, skinned, cooked, or thermally processed.
How Reclaimed Water is Produced
Reclaimed water is wastewater that has received, at a minimum, secondary-level treatment and basic disinfection at a wastewater treatment facility. There are three stages of wastewater treatment. Primary, secondary, and advanced.
- Primary treatment – Suspended solids are removed by screening and settling
- Secondary treatment – Biological decomposition reduces complex organic material into simpler forms. Water is then separated from any remaining organic material and then either disinfected and directly discharged, reused, or subjected to the next step.
- Advanced treatment – Facilities that further remove solids, organic material, nutrients, or other chemical using physical, chemical, or biological processes.
- After advanced treatment water is then disinfected before being discharged in rivers, lakes, or coastal waters, or reused.
- Tertiary treated water typically has 25% of the nitrogen and phosphorus contained in secondary treated reclaimed water.
There are no federal regulations governing the use of reclaimed water, but the U.S. E.P.A has established guidelines to encourage states to develop reuse programs. Depending on how reclaimed water is to be used in Florida, there are specific treatment requirements. More information on Florida’s reuse program can be found on the website of the Florida Department of Environmental Protection at http://www.dep.state.fl.us/legal/rules/wastewater/62-610.pdf.
Small steps for water conservation can make big differences for the future. Being aware of the problem is just as important as making every effort to fix it, or at lease slow down the process. For more water conservation publications visit edis.ifas.ufl.edu or contact your local Extension Office.
Chris Vann- Extension Agent- Agriculture/4-H