Overcoming Drought Part III: Saving Waste to Water
Glancing down at the toilet, you probably don’t givemuch thought to the fate of the swirling water as it flushes out of sight. Didyou know, for example, that an estimated 1.7 billion gallons of wastewater arereused every day, just a fraction of all discharged wastewater,with a potential growth rate of 10-15 percent per year? If you live in an areaprone to drought, where your water supply could be restricted, if you’relooking for possible long-term cost savings on water, or if you just happen tobe concerned about the future of our fresh water supply, you may want to startthinking about wastewater as an alternative irrigation source–the treatedkind, that is.
Save water, save money
Whiting Preston, president of Manatee Fruit Co./ManateeFloral, Palmetto, Fla., started working with reclaimed water approximately 25years ago. Because Manatee is conveniently located right next to the treatmentplant, the city asked Preston to take the plant’s reused water because itneeded to dispose of it. Manatee originally used the reclaimed water toirrigate its gladiolus. “What it did for us is that we didn’t haveto pump our well, we were able to use the water, and there was definitely a[cost] savings,” Preston said. Since there was never a guarantee that thecounty would be able to consistently follow through with the water delivery,however, Manatee kept its water-use permits for the use of groundwater fromwells, which it uses intermittently to balance out its water distribution.
Transportation of the reclaimed water from the treatmentfacility to the growing operation was easy because of Manatee’s closeproximity to the plant. The county installed a water recovery system so Manateecould retain all the water that was pumped out to them within a pond. “Inan effort to conserve water and decrease runoff,” Preston explained,”the county installed a pump-back system on the tail of the farm.” Manateeused the water in the greenhouse for some of the cut flowers and has notnoticed any adverse effects on the plants grown in the ground beds or sandysoils due to water quality issues. Preston has, however, noted difficultieswith soilless medias, which has made further internal filtration necessary,though not to the point where it’s potable.
“There is an obligation on the part of the user ofthis water not to have people drink it, and that’s certainly a concern ofours. We post signs to keep people from drinking the water, and they’rewilling to cooperate. Reused water has to meet certain standards, and since thecounty has to be within those standards, they give us a report to let us knowwhat kinds of elements are in it,” Preston said.
Manatee has not had to pay for its reclaimed water since thebeginning of the agreement many years ago, but Preston doesn’t know thatthat’s going to continue. “I think that over time, treatedwastewater is going to become a marketable commodity as it becomes more and moredifficult to receive water rights for your farm and land. It’s anexpensive process, but I think it’s also going to become more valuableand more expensive to pump groundwater.”
Manatee’s case may be an anomaly; for most businessesinterested in reclaiming water, their counties may be unable to foot the billto dispose of their water and assist in retrofitting costs. Such was thesituation with Color Spot Nurseries, headquartered in Pleasant Hill,Calif., which has been using tertiary-treated water since 1999. Growers in Californiawho have access to tertiary-treated water are required by law to use it ontheir nursery crops. Color Spot had to set up the necessary specifications forthe water from the plant, involving soil laboratories to determine the maximumsalt levels the nursery could tolerate through their primary source of water.The water treatment plant then guaranteed them that they would produce waterwithin a certain salt range and plumbed it in through an 18-inch line.
Though Color Spot did not receive any governmentalassistance with retrofitting, it has still benefited tremendously from the costsavings of using treated wastewater. “The water was approximately 30-40percent cheaper, so there was a cost benefit for us,” said Jim Crockett,environmental and regulatory affairs manager for Color Spot. “We couldlive with the salt levels fairly well, but we decided that we also had to putin a blending station. We had to re-learn how to grow certain sensitive crops alittle bit differently, so it was probably about a 3-year learning curve afterthe installation.”
The West and Central Basin Municipal Water District inCarson, Calif., treats industrial and domestic wastewater to secondary levelsand regularly pumps it out to the ocean 4-5 miles off the coast. A portion ofthat water is sent to its treatment plant where it is treated to tertiarylevels, and then can be sold to individual recycled water purveyors. Theseretailers sell it to qualified end-users. “On a wholesale basis, therecycled water is available for approximately 50 percent less relative toimported water. As a general rule, the discount to the end-user is somethingalong the order of 20-30 percent less than they’d pay for imported water.That tends to be the largest incentive for people–the reduction in costfor water,” said Mark Tettemer, recycled water project manager for Westand Central. The other important benefit nearly goes without saying–constant access to a drought-proof supply of water.
West and Central pays for the water distribution system upto the meter, which is the responsibility of the individual purveyor.Downstream of the meter there are further modifications, called on-siteretrofits, which are the responsibility of the end-user. “To try toeliminate [the retrofits] as an obstacle from a capital funding perspective,we’ll help finance those on-site improvements. We’d like to see ourexpense for the retrofit repaid in 10 years. To make it sort of an invisible capitalcost, we’ll continue to charge them their potable water rate, andwe’ll use the difference between the potable and recycle rate forrepayment. So they’ll continue to pay their existing water bill rate overthat period until it’s repaid, and in essence it’s not really costingthem anything,” Tettemer said.
And what’s involved with retrofitting? The objectiveis to separate the domestic water from reclaimed water supplies. Mostfacilities receive a single supply of domestic water that they split off forirrigation needs, but to receive reclaimed water, there must be a separatedistribution system built in. The signature color used for reclaimed water pipeis purple; this pipe would be connected where a normal, single-distributionwater system has a backflow device for irrigation.
If any of this has peaked your interest so far, you probablywant to know where you can sign up to get started. Unless you live inCalifornia, Florida, Texas or one of the other states that regularly struggleswith water restrictions, you may have to be willing to do some footwork.”Usually what ends up happening is if you’ve got a water districtthat’s looking to start recycling water, they’ll go out and lookfor customers,” said Rick Martin of the U.S. Bureau of Reclamation.”In California, many of the water districts that are doing recycling willsell the water for about 80 percent of what potable water would cost.You’ll have to do some retrofitting of pipes, and then there’salways the issue of whether or not, depending on the types of plants you’regoing to water, the total dissolved solids (TDS) level in the reclaimed waterwill be too high.” In general, if you’re interested in usingreclaimed water, you should contact your local water purveyor to see if thereis a pipeline running within the vicinity of your operation.
There are also certain qualifications that must be met,according to Tettemer. In the case of the West and Central Basin MunicipalWater District, there are two steps involved in the approval process.”First, does the collective of potential customers economically supportthe project?” he said. If the project can be supported, thesecond step is to work with individual customers to assess whether or not theycan persuade enough of them to subscribe to take the water. With enoughsubscribers, West and Central can then move forward with the design andconstruction of the pipes to resolve the on-site retrofit issues, Tettemersaid.
Additionally, there are individual state regulations.”Most states now have regulations on recycled water for variousapplications and whether or not it’s suitable for human contact ornot,” explained G. Wade Miller, executive director of the WateReuseAssociation. “The water, depending on the application, would have to betreated to whatever standard is specified for the application in the stateregulations.” California, for example, has a written code that identifieswater quality standards that must be met to qualify for certain applications.But if you can’t meet these qualifications, if you aren’ t withinclose proximity of a wastewater treatment plant, if there aren’t enoughpotential customers in your area to use the water, there?s stillsomething you can do: get political.
Educating the masses
“It takes a lot of political will to take a program likethis to fruition because it’s tens of millions of dollars to constructfacilities if [a municipality] doesn’t have the capacity to do that. Ithink it’s appropriate that everyone consider it and then move on to whatthey can do to make it work,” offered Tettemer.
A municipality can qualify for 25-50 percent of projectdevelopment costs through a U.S. Department of Reclamation program, but thusfar, only 22 projects have been authorized in the past 10 years, according toMiller. Some states have created grant and loan programs, as in California,where Proposition 13, passed in 1999, created a $100 million grant/loan fundfor large projects. “For a small user, it would really come down to theeconomics and availability of water and if this is the best alternative,”Miller added.
So does it make sense to use reclaimed water in areas wheredrought is an infrequent issue or where the water transportation infrastructureis not there? Since there are different variables involved in many cases,including varying water rates and other economic issues, it depends. What ismost needed right now is education. “It’s going to take awhile toeducate the planners and municipalities and politicians that this is a greatway to augment existing sources of supply,” said Miller. And even at justthe general public level there’s a lack of awareness: “People thinktertiary-treated water is not even treated,” Crockett said.
The WateReuse Association is trying to make headway on theeducation front by organizing a government-wide, multi-agency task force thatwould execute an inventory of various water reuse programs and practices andthen look for potential opportunities. “If we can get this piece oflegislation enacted,” Miller continued, “it requires a report tothe president and congress within the next 18 months. That would put waterreuse on the radar screen. We?ve made tremendous progress in the last fewmonths, and hopefully by the end of the session, we’ll have gotten somegood results.”
The key here, however, is to be proactive about your watersource before you have to react to the government regulations that may comewith increased federal awareness of the issue. Crockett, who is planning tostart lecturing on water reuse next year at the Southeast Greenhouse Conference,believes it’s critical that growers begin to consider water recycling andreclamation now, while there’s still time. “You need to startplanning now, before you’re forced to do it and you won’t have theflexibility. And if you set up right to begin with, you’ll be ahead ofthe curve. You’ll become the model, instead of you trying to conform to amodel that some engineer in the Department of Public Works developed because hedoesn’t know our industry.”