Water quality: Not quite, but almost, rocket science


Remember learning about “if-then” statements in algebra class? The statements proved that if something happens, then something else will happen, or is true.

If x + 2 = 4, then x = 2.

The logic holds true outside of mathematics, too. For example, if I live in Nebraska, then I live west of Ohio.

(Of course, there are “if-then” statements that defy logic, but are gospel truth, nonetheless: If you get a Red Ryder Carbine-Action Two-Hundred-Shot Range Model Air Rifle, then you’ll shoot your eye out, kid.)

But sometimes life is more complicated than if-then logic statements. You never figured on factors like X, Y or Z when you were charting your best-laid plans. Soon, the if-then contingencies start branching off like multiflora rose.

I thought about all this as I listened to Kevin Elder, Ohio’s manure guru, at last weekend’s Power Show Ohio.

Elder, executive director of the Livestock Environmental Permitting Program within the Ohio Department of Agriculture, was explaining the toxic blue-green algae and water quality problems that closed Grand Lake St. Marys in western Ohio and hit 25 other lakes last summer.

Agriculture is the primary land use in the Grand Lake St. Marys watershed, and farmers there will be a major part of the restoration efforts. But don’t think just because you don’t farm in that watershed, you’re off the hook. We’ll be hearing lots more about watershed protection and regulation across the country, as states are mandated by the Environmental Protection Agency to establish nutrient standards for water bodies.

However, every watershed — and every farm, even every field, and every farm manager — is different and there’s the rub. There’s no easy, “if we do this, then everything will be honky-dory” solution.

Farm discharges or runoff vary with land use, cropping history, production practices, fertilizer use, livestock production, drainage, compaction, soil types and management practices, even earthworm activity, just to get started. Weather, temperatures, amount and intensity of precipitation — which we can’t control — also play a major role.

As I listened, I learned “dissolved reactive phosphorus,” or DRP, is a new yardstick to measure water quality. Problem is, Ohio EPA measures total phosphorus, and Ohio farm manure management plans use total phosphorus as a basis, not dissolved phosphorus. Dissolved phosphorus, Elder says, flows with water and is more difficult to dilute.

There are no real Best Management Practices for reducing dissolved reactive phosphorus, Elder added, but there are practices we know will lower the risk of discharge and increasing concentrations in runoff.

Nothing novel here, folks, just good ol’ agronomic practices: Soil test (and then heed what the test tells you); know the agronomic standards and recommendations for your soil type; calibrate your equipment; and, use some common sense (you don’t need to keep applying manure or fertilize if your field if it doesn’t need it).

No, cleaning up Grand Lake St. Marys, or any water body, won’t be that easy, and it may be akin to rocket science, but it does command our attention.

If we don’t listen, then we might be in big trouble.


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  1. I’m not sure what Kevin Elder may have done to help GLSM and the other Ohio lakes – but I am sure of what he’s done that may have harmed these lakes.

    His office has approved every concentrated animal feeding operation (a.k.a. factory farm) permit submitted in the past ten years, except one which is currently in dispute.

    His office has systematically reduced or rescinded environmentally-protective LEPP regulations in order to approve some permits which did not comply with their original Program. These rules were originally developed by a diverse group of scientific professionals and representatives from the ODNR, USGS, NRCS, and Ohio EPA.

    His office has approved additional manure applications on fields with phosphorus levels already TEN times higher than the agronomic needs of the crops, as well as on frozen and snow-covered fields.

    The ODA has become a textbook example of “agency capture” wherein it has become so identified with large animal producers that it has become an extension of these developers. Elder knows the practices to lower the risks of discharge – but in the words of Upton Sinclair -“It’s difficult to get a man to understand something when his salary depends upon his not understanding it.”

  2. I agree that agroecosystem management is complex, but we can choose to the extent that we make is complicated. Saying that managing land for water quality is more complicated than rocket science is akin to say that managing land for corn production is more complicated than rocket science. All the same variables exist for both. The only difference, and it is a major one, is that we get to directly measure how many bushels of corn at the end of the management cycle. But we also ‘measure’ corn production throughout the growing season using data and indices – and the ‘measurements’ are provided down to the tenth of a bushel and the usually end up within a few percentages of actual production. This measurement strategy is good enough for ecoservices. More info and reviews of this EcoCommerce model is a http://www.ecocommerce101.com and this book will be released February 10th.


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