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E-M:/ manure contributing to Lake Erie dead zone



Evidently this didn’t post to E-M yesterday – second try:

 

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Anne Woiwode, Director

Sierra Club Mackinac Chapter

109 East Grand River Avenue,  Lansing, MI  48906

ph: 517-484-2372 fx: 517-484-3108 e: anne.woiwode@sierraclub.org

website:  http://michigan.sierraclub.org

 

-----Original Message-----
From: Anne M. Woiwode [mailto:anne.woiwode@sierraclub.org]
Sent: Monday, August 09, 2004 6:18 PM
To: 'Dolan, David'; 'Janet Kauffman'
Cc: 'enviro-mich@great-lakes.net'; 'Pete Richards'
Subject: RE: E-M:/ manure contributing to Lake Erie dead zone

 

I appreciate the discussion here and agree that the phosphorous problems in the Great Lakes, and the “dead zone” in Lake Erie need to be accurately understood, with a full look at all the factors involved.  Recognizing I don’t have all those facts, I nonetheless wanted to add a couple of observations:

 

1) the CAFO boom in Michigan started after 1999, after the agriculture industry stripped out most or all of the regulations at the state and local level constraining the growth of this industry, so ten year old numbers could well fail to represent the situation;

 

2) While the Agricultural Year book for Michigan for 2001/2002 showed a decline in the number of dairies in the state from 3500 to 3300, it showed an increase in the amount of milk produced from 5.70 million gallons to 5.85 million gallons – the waste is likewise also increasing. 

 

3) even a declining number of animals producing concentrated liquefied wastes that are spread year round could be causing a significant increase in the pollution load simply because the technology is so dramatically different from older systems that provide the normal model for comparison;

 

3) the estimates of the sources of phosphorous are likely based on modeling, not observation. As has been shown by the extraordinary documentation done by Janet Kauffman and others with Environmentally Concerned Citizens of South Central Michigan, field application of liquefied CAFO wastes OFTEN causes almost immediate discharges of CAFO wastes through field  tiles into surface waters in the Lenawee and Hillsdale County areas of Michigan.  Observations are really needed to document the effects of CAFO wastes contribution through soils (including through injection into the soils) and into field tiles to surface water pollution, but so far only volunteers have been willing to conduct systematic observations of the sorts needed, and they have an uphill battle getting agency attention.

 

I very much appreciate Dr. Dolan’s comments about the need to properly handle CAFO wastes, and the need to address all the sources.  I think the greatest challenge in Michigan has been the fight against any regulation of any agricultural pollution sources, even those like CAFOs that are clearly major sources of at least localized pollution problems as well as potential contributors to the declining health of our Great Lakes. 

 

Anne Woiwode

 

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Anne Woiwode, Director

Sierra Club Mackinac Chapter

109 East Grand River Avenue,  Lansing, MI  48906

ph: 517-484-2372 fx: 517-484-3108 e: anne.woiwode@sierraclub.org

website:  http://michigan.sierraclub.org

 

-----Original Message-----
From: owner-enviro-mich@great-lakes.net [mailto:owner-enviro-mich@great-lakes.net] On Behalf Of Dolan, David
Sent: Monday, August 09, 2004 5:36 PM
To: Janet Kauffman
Cc: enviro-mich@great-lakes.net; Pete Richards
Subject: RE: E-M:/ RE: / manure contributing to Lake Erie dead zone

 

A Reply to Janet Kauffman:

 

You are certainly right that there are CAFOs elsewhere than in northwest Ohio; we addressed our comments to the situation in northwest Ohio because that was the focus of the Plain Dealer article.  Certainly all of the animals in CAFOs contribute to Lake Erie’s phosphorus loadings.  So do all the other land uses in the basin.  The total animal population has been contributing to the phosphorus loads entering Lake Erie for many years, however, so it is increases in the population that are of greatest concern.  Trend studies for northwest Ohio (Maumee and Sandusky basins) done by the Water Quality Lab showed that the farm animal population declined in this region between 1975 and 1995, as did the amount of manure applied.  The WQL also detected a decrease in total phosphorus concentrations in the Maumee and Sandusky Rivers of more than 40% during this time.  Another part of the study showed that phosphorus being applied to the land was 75% from fertilizer, 20% from manure, and 5% from other sources, on average, during this time period.  These studies were published in the January 2002 issue of the Journal of Environmental Quality; Pete Richards will gladly email a pdf version of the relevant papers to anyone who wants one.  Obviously, there is now nearly a ten-year gap between the end of the study period and the present, and updated studies are warranted (but not funded).  Still, these figures may be useful in putting the current issue into perspective. Similar analyses could be conducted for the River Raisin because it is also in the Water Quality Lab’s monitoring network and has been sampled frequently enough to detect changes. The sampling of Ontario tributaries is not so good, especially in recent years. Undersampling usually leads to underestimation of impacts and this is a concern that we continue to raise.

 

The figure of 10% phosphorus delivery to Lake Erie is not based on any specific studies, but is based on judgement informed by many discussions with individuals who are actively involved in studying problems of preferential flow.  In addition, a number of studies of the transport of nonpoint pollution through tributary networks have arrived at figures in this ballpark.  Earthworm and other burrows can indeed allow liquid manure to reach tiles and hence streams, as can soil cracks under some circumstances.  Ironically, these problems are worse with no-till farming than with conventional tillage.  Preferential flow also facilitates the movement of any other form of phosphorus through the soil to tiles; its impact is not confined to liquid manure.  It is also certainly true that most of the manure applied in liquid form does not drain to tiles in this manner.  Techniques such as incorporation of manure into the soil, and soil disruption to minimize preferential flow, can and should be utilized to minimize migration of manure-based and other nutrients from the field.

 

Our water quality data do not show an upturn in phosphorus loading to Lake Erie.  There have been years of high loading and years of lower loading, a consequence of varying weather patterns from year to year.  In addition, we believe there is a consensus among those who work on the reappearance of Lake Erie’s “dead zone” that it is due largely to changes in nutrient cycling within the lake (primarily a result of the zebra mussel invasion), not to increased external loadings.

 

In any case, we do not wish to see external phosphorus loads to Lake Erie increase, and we support measures that will help to prevent such increases.  We support field application of nutrients (from any source) in amounts that do not exceed plant uptake requirements for phosphorus.  We support the informed use of soil fertility tests to limit nutrient buildup (see, for example, http://ohioline.osu.edu/b604/b604_15.html). We support application of manure by injection, and avoiding application of manure or other fertilizer in the fall and winter, particularly onto bare or frozen ground.  We believe that all sources of phosphorus need to be better managed, including agricultural sources, urban runoff (which often contains higher concentrations of phosphorus than rural runoff), septic systems, and municipal and industrial effluents.  We do not think that singling out CAFOs as the problem is helpful in this regard.

 

 

R. Peter Richards, Ph.D.                                 David M. Dolan, Ph.D.

Water Quality Laboratory                               Dept. Natural and Applied Sciences

Heidelberg College                                         University of Wisconsin-Green Bay

Tiffin, Ohio                                                     Green Bay, Wisconsin

prichard@heidelberg.edu        doland@uwgb.edu