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Grass may solve sewage dilemma Rich Roseburg By MELISSA MARTIN Mail Tribune WHITE CITY - Miscanthus and a poplar plantation may help solve a regional wastewater disposal problem. A city of Medford experiment using treated sewer water to irrigate ornamental grass and a tree plantation has been so successful that plant managers hope to expand the program to 4,500 acres of fiber crops over the next 20 years. The city faces a federal deadline to find an alternative way to dispose of the 14 million gallons of treated waste water discharged into the Rogue River daily from the regional treatment plant on Kirtland Road. The Environmental Protection Agency will soon limit or prohibit inflows that raise the river temperature more than quarter-degree Fahrenheit because high water temperatures aren't good for salmon. Miscanthus doubles as fuel Miscanthus grass produces an annual cutting, much like hay, that can be sold as a "hog" fuel to a co-generation plant such as Biomass One. An acre of miscanthus offers about 10 dry tons of fuel annually, which could yield a farmer $300 an acre, about the same as wheat, barley or alfalfa, said Rich Roseburg, Oregon State University soil scientist. A 10-year-old poplar plantation can yield $1,000 an acre annually if the trees are thinned and grown big enough for dimensional lumber, according to a study done in Malheur County. One of the drawbacks of using poplar as dimensional lumber is the lack of quantity, Roseburg said. A 3,000-acre poplar plantation would only run a typical sawmill for 9 or 10 days, he said. Large paper companies in Washington are growing thousands of acres of poplars for pulp mills, he said. If the trees grow to eight inches or larger, they can be peeled and sold to a veneer plant to reap a higher value. At the regional wastewater treatment plant, the discharge is nearly 75 degrees Fahrenheit in the summer, plant managers said. But in the winter, even though effluent temperatures are lower, the river runs in the low 40s, making it impossible to avoid violations. The city considered two options: $31 million for a cooling system to refrigerate the water before it returns to the river; and $21.3 million to reuse the effluent by piping and pumping it to regional farms for crop irrigation. Both options include a secondary treatment process to further filter the water and expand plant capacity. But the cooling option would add $1.6 million more in annual operation and maintenance costs while the re-use option would add $817,000 in expenses each year. "The reasons we favor the reuse alternative is partly because of economics," said Jim Hill, wastewater reclamation administrator. "It's outrageously expensive and a true waste of energy to cool the effluent. "This option has environmental benefits of supporting agriculture, improving flows in Bear Creek and Little Butte and improving water quality in the Rogue River." He's been meeting with watershed council members and the Bureau of Reclamation to talk about pumping the treated sewer water to the dry Sams Valley or through the Rogue River Valley Irrigation District system. Farmers concerned about using treated wastewater for food or forage crops could be reassured that the effluent would have no bacteria or pollutants, Hill said. The city of Medford has used advanced treatment methods to satisfy the Clean Water Act since 1971. "We would ensure the level of treatment provided would be adequate to grow any crops," Hill said. Nutrient-rich water could be a bonus for crops, said Rich Roseburg, an Oregon State University soil scientist. "(The effluent) has 40 pounds of phosphorous per acre and 90 pounds of nitrogen per acre and the heavy metals are low," said Roseburg, who's working with the city on the crop experiment. In 1996, he planted experimental poplar plots at the regional wastewater treatment plant in White City. Roseburg has been monitoring two ground water wells and 30 devices that measure the impact of irrigation water on the soil. "We've never detected an increased level of nutrients or heavy metals in the soil," he said. The poplars and miscanthus may be the answer to new discharge restrictions expected in the city's draft permit from the state Department of Environmental Quality, said Harley James, wastewater reclamation facility superintendent. The new permit, which is supposed to arrive next month, may prohibit river discharges. New regulations will likely mean rate increases for the 108,000 customers served by the Regional Water Reclamation Facility, which treats sewage for the cities of Medford, Central Point, Jacksonville, Talent, Phoenix, Eagle Point and Bear Creek Valley Sanitary Authority. Medford customers pay the lowest sewer rate in the state at $4.66 per month. If the city went with the effluent cooling option, rates could increase by an estimated $4.50 per month and sewer system development charges would jump by $400 per home, Hill said. With the re-use project, rates could increase by about $2.50 per month and no increases are predicted in sewer system development charges. All projects and increases would occur over the next 20 years. Reach reporter Melissa Martin at 776-4497, or e-mail [email protected] Mail Tribune Home | Ottaway Newspapers, Inc. | Dow Jones & Co., Inc. | Privacy | Contact Us Copyright � 2001 Mail Tribune, Inc.