Recycling Water for Irrigation
|By ROBIN WESTMILLER|
Say the word `recycling` and what usually comes to mind is taking aluminum cans. Glass bottle and newspapers to a recycling center and turning them in for cach. But did you ever consider that there might also be money to be found in recycled water? Recycled or reclaimed water refers to wastemater that has gone through a sewage treatment plant or reclamation facility, where it`s treated to remove bacteria and pollutants, recycled or reclaimed water is odorless, colorless and pure enough to use in a number of applications, including industrial processing, cooling towers, and dust control at construction sites. In fact, recycled water can be used for just about every need, except human consumption.
But the single largest use of recycled water is in landscape irrigation.
“Using reclaimed water to irrigate landscapes isn’t a new idea,” says Doug Venable, environmental compliance technician with the El Dorado Irrigation District, El Dorado Hills, California.” Recycled water has been used successfully in California, Florida, Arizona, North Carolina and Texas for many years. In fact, the first regulations regarding the use of recycled water in California were adopted in 1918. But it really wasn’t until the beginning of the 21st century, with water conservation and increased drought concerns, that using recycled water for landscape irrigation really started taking off.”
In 1999, the El Dorado Irrigation District (EID) obtained state approval for the installation of recycled water irrigation in the front and backyards of about 3,500 homes in the city of Serrano. Since then, hundreds of residential lots have been receiving recycled water, and in 2003, the EID mandated that any home built within the district’s service area is required to use recycled water.
“When new homeowners move into town, they receive an information packet describing the recycled water system, and a list of the authorized contractors they can contact to hook them to the system,” said Venable.
Shortly after the ordinance went effect, Michael Ulrich, president of Big Green Landscaping in El Dorado Hills, California, became one of the first landscape contractors in his area to become authorized by the EID to design and work on recycled water lots.
“We’ve seen a huge increase in business once the EID mandated that houses had to be hooked up to their recycled water system, but we didn’t stop with just offering that service,” says Ulrich. Our company focuses on ‘green’ awareness, including providing our clients services related to water conservation—creating sustainable, low maintenance landscapes and using recycled water is a great way of getting our foot in the door.”
Because homeowners in the EID service area don’t have the choice of using recycled water or not, developers have previously installed the infrastructure for recycled water in every home built within their service area.
“When new residents move in, their front yard is already completed for them, but it’s up to them to install the recycled irrigation system in the backyard; for that, they need to call one of the EID authorized landscape contractors,” says Venable. “The companies listed have attended one of our recycled water workshops; they know the rules, and the homeowner can be confident that the contractors are qualified to install recycled systems on their landscape.”
Taking the workshop and becoming an authorized contractor also gives you other opportunities to increase your business by getting to know new residents and offering other services to a new client.
“When new homeowners move into the city, they receive the information package on the recycling program, which includes our company information, including the services we provide and our contractor’s license number,” says Ulrich. “Some people will put in a lot of turf, or use the backyard to install a pond or a decorative fountain or other water feature, and we can hook everything up to the recycled water system for them, because we know the proper procedure the EID wants.”
California is far from the only state that is seeing a huge increase in the demand for recycled water use for irrigation. Across the country, developers and municipalities are becoming more invested in installing sustainable landscapes to meet eco-friendly standards, and the incentives to join this trend have never been greater.
“In 2001, Cary became the first city in North Carolina to pump treated wastewater to homes and businesses for irrigation,” says Rick Jordan, reclaimed water coordinator, town of Cary, North Carolina. “We began with one treatment plant that recycled a total of about five million gallons a day. Today, we have two operational reclamation facilities that together have a capacity of more than 24 million gallons a day, and a third reclaimed water distribution system is being built that will s e r v i c e t h e western part of the city and two neighboring counties.
T h e a r e a where the new r e c l a m a t i o n plant is being b u i l t h a s already been identified for recycled water. So the irrigation systems for all new homes and businesses in that area will be installed to reclaimed water standards,” Jordon said.
Reclaimed water standards simply means that all pipes and equipment conveying recycled water must be purple or have purple markings, as a universal sign of reclaimed water, to prevent cross connection with potable water supplies. This includes flow control knobs, valve boxes, sprinkler heads and, of course, all piping—whether or not there is recycled water available at the time.
Installing a reclaimed waterready irrigation system can be a huge money-saver down the road, once recycled water becomes available. While reclaimed water, by law, can only flow through purple pipes, potable water can run through any pipes, so you can install purple pipe on a new construction site, with an eye towards the future. In the meantime, the reclaimed waterready system can use potable water until recycled water becomes available. Once the recycled water is available, you can switch over.
“When the main city recycled water line is extended into those areas, you won’t have to dig up the irrigation system, or tear up the yard, if you have this system installed ahead of time,” says Jordon. “Even if those customers are using potable water now, once the reclaimed lines become available and they want to switch, it’ll be very easy to hook them up, since the purple pipes will already be installed.”
You can see that having a good supply of purple irrigation components is a good idea if your business is in an area that has, or is planning to build, a water treatment center. By installing purple irrigation components during new construction, it could potentially save your clients thousands of dollars down the road, and they’ll be able to start using the recycled water immediately once the system comes online.
Another benefit to using recycled water for irrigation is that recycled water has a much higher nutrient content than potable water. In general, all recycled water contains some amounts of boron, calcium, chloride, sodium, sulfate and trace amounts of other elements which are very beneficial to plants and trees.
“By using recycled water, grass and plants will be able to obtain all the nutrients they need naturally,” says John Sullivan, CIC, CLIA,
CLWM, managing partner, Green- Wave Associates, Gastonia, North Carolina. “In fact, because the primary nutrients in most reusable waters are nitrogen, phosphorus, and potassium, using recycled water on turf will help reduce or even eliminate the need to fertilize, which also reduces the cost of material and labor.”
With all the great benefits to using recycled water for irrigation, it would seem that wherever there’s an opportunity to connect to a recycled water service, everyone would be doing it. But before you decide to jump into the recycled water pool, there are specific challenges that you’re going to need to address.
In addition to having to take the time to attend special workshops and training that many cities provide, special irrigation plans may need to be drawn in accordance with that district’s design and construction standards.
“As in just about everything else in construction, this type of irrigation installation varies by each district’s rules and regulations,” says Sullivan. “Some municipalities require two sets of plans plus two additional sets for the homeowner and the contractor. Another small headache is that plan approval can take up to two weeks or more before we can start the job. Then, of course, there’s the inspection process after the job is completed, but in all the years I’ve been working in the North Carolina area, we’ve never had a serious problem.”
David Morris, public affairs manager of the Albuquerque Bernalillo County Water Utility Authority in Albuquerque, New Mexico, says the procedure of contractors in their service area has been finetuned to make the process go smoothly.
“Our big recycled water project won’t be completed until this fall, so it’s a bit early to make any future predictions, but the process is already in place,” says Morris. “All a contractor would need to do is get in touch with us to determine whether or not they can be connected to the recycled system from an engineering perspective, and we have certain procedures that need to be followed.
We’ll proceed from there.”
Paperwork aside, the amount of nutrients contained in reclaimed water also varies from utility to utility and can vary at different times of year, so it is important to know the nutrient content of the water you receive so you can incorporate this source into a landscape fertility plan.
Of particular importance to landscape health are the salts and nutrients in reclaimed water. Special management practices may be required, depending on the quantity of salts supplied in reclaimed water and the salt-sensitivity of the plants irrigated.
Another area of concern with the salt content in recycled water is the negative, sealing effect that sodium and other elements have on soil permeability. A good practice is to take soil tests periodically to check the makeup of the soil.
If you’re installing a conventional recycled water irrigation system, another component you’re going to need is an effective filtration system. There are a lot of organics in recycled water and they make a good source of food for algae. A good filter will remove any residual suspended matter from the recycled water, as well as any algae build-up that enters the irrigation system.
“To avoid potential clogging of sprinkler nozzles when using reclaimed water, we usually recommend a filter that has a screen of 125-130 microns,” says Jim Lauria, vice president of marketing with Amiad, Oxnard, California. “In addition, for large commercial properties, I’d recommend having a self-flushing filter on the mainline to be on the safe side, just in case an occasional solid gets through.”
Most of your potential clients already have some knowledge of a recycled plant nearby, or if there is going to be recycled water available in their community, sooner or later. The key is to be able to answer their questions about how the system works, and to show your clients all of the ways that using recycled water for their irrigation is going to help save them money in the long run.
Water recycling has proven to be effective and successful in creating a new and reliable water supply without compromising the quality of the landscapes. Using recycled water for irrigation is becoming a widely accepted practice that will only continue to grow.
For contractors, when a municipality puts in a reclaiming and recycling facility, it’s the start of something green.