More than 16,000 U.S. wastewater treatment facilities serving more than 220 million people produce sewage sludge, according to a survey cited by the U.S. Environmental Protection Agency (EPA).
A significant portion of that material is turned into biosolids available to farmers for fertilizing crops. And, as commercial fertilizer costs continue to soar, those biosolids are increasingly prized for their ability to reduce crop fertilizer bills by providing nitrogen (N), phosphorus (P) and some secondary and micronutrients for crops. They also provide organic matter.
If you haven't checked into a source of biosolids for your cropland, you may be missing out on a major savings. Among those to contact for availability are: your local wastewater or sewage treatment plant, local Extension educator, farm management consultant or land grant university.
Supply is far from open-ended. You might find yourself on a waiting list, with only limited amounts of biosolids available.
FARMERS BOB CLAUSEN and Ron Bopp in eastern Nebraska accepted biosolids on some of their fields from the municipal wastewater treatment plant at Fremont, NE, several years ago. They were among the first to try the material in their area.
Biosolids were applied at rates required to meet corn N needs, based on soil tests and these farmers' yield goals for their fields, says Ron Schultz of the Pathfinder Company in Fremont. He's the farm manager for their farms.
Commercial N needs on those fields have been met with commercial sources of N for corn in subsequent years. But, the only commercial P for corn and soybeans on those acres since 2002 has been a starter application of 10-34-0. No other P has been needed, say Clausen, Fremont, NE, and Bopp, Hooper, NE. And, that was on fields where soil tests showed low P levels before applying biosolids, says Schultz.
Clausen says corn and soybean yields on those acres — one 50-acre field and another of 40 acres — have equaled or beat corn and soybean yields from his other fields where he usually applies 100 lbs./acre of 11-52-0 annually.
Bopp has experienced similar results on 145 acres of irrigated land, where he had biosolids applied from the Fremont wastewater facility. “I haven't used any (commercial) P since,” he says.
Corn and beans have yielded as well or better than other fields fertilized regularly with commercial fertilizer applied according to soil tests, Bopp says. Biosolids not only cut his fertilizer bill, they improved soil tilth, he adds.
He calls it a “huge savings,” but adds, “The only problem is, there aren't going to be enough (biosolids) to go around.”
The material, Class B, from the Fremont plant is about like potting soil, according to Schultz. It spreads evenly. You don't get the clumps that can occur with livestock manure spread on fields, he says.
Bopp disked in the biosolids he received, which were applied in the fall, and then incorporated further with field cultivation in the spring. Clausen says he incorporated biosolids on some acres and not on other acres, with comparable yield results between the two.
“Environmentally, it's a grand way to get rid of a product from these (municipal wastewater treatment) plants,” Bopp says. And economically, the more fertilizer prices rise, the farther you can transport it for its fertilizer value, he adds.
Clausen and Bopp are among a group of Nebraska farmers who are comparing biosolids processed from municipal sewage sludge for crop production. They participate with the Nebraska Soybean and Feed Grains Profitability Project, an on-farm research program.
Biosolid substitution for commercial fertilizer is just one of many different practices farmers are researching for themselves on their farms. They receive guidance on setting up accurate comparisons from University of Nebraska Extension personnel. (You can review past results at http://farmresearch.unl.edu by searching biosolids.)
University of Nebraska Extension Educator Dave Varner in Dodge County, NE — where Clausen and Bopp farm — says farmers receiving biosolids from the Fremont plant have generally e