Pork industry's "one percent illusion" debunked

For months, a pseudoscientific, low-ball estimate by the Manitoba Pork Council of the amount of phosphorus its industry contributes to Lake Winnipeg has gone essentially uncontested in the media. The power of suggestion has even led credulous reporters to depict is as the result of published studies. Yesterday the big lie was duly debunked on the op-ed pages of the Winnipeg Free Press.

The one per cent illusion
Pork industry shirks its responsibility for water woes

Thu Jan 25 2007

By Alan Baron

LATE last year, the Manitoba Pork Council astounded many Manitobans with full-page newspaper ads proclaiming that hog manure contributes a mere one per cent of the total phosphorus load to Lake Winnipeg.

Shortly after, one of my colleagues obtained an unpublished document outlining the assumptions upon which the MPC estimate is based. Upon reading these Technical Notes by Don Flaten, a University of Manitoba soil scientist, it becomes immediately obvious that the Pork Council is seeking to perpetrate a one per cent illusion upon Manitobans.

As Flaten himself cautions in the document: "The one per cent estimate is not a precise figure; it's a rough estimate with some substantial assumptions."

Substantial assumptions indeed.

The most substantial of these assumptions is that all agricultural sources of phosphorus -- from synthetic fertilizer applied by grain farmers to liquid hog wastes disposed of by industrial hog barn owners -- move at an equal rate into Manitoba waters, especially Lake Winnipeg.

Applying this assumption to data from the Lake Winnipeg Stewardship Board's 2005 Interim Report and other sources, the MPC makes the following calculations.

Of the total phosphorous load to Lake Winnipeg from all sources, Manitoba agriculture contributes 14 per cent. Of the agricultural phosphorus applied in the province, 85 per cent comes from synthetic fertilizer. The remaining 15 per cent comes from manure, 55 per cent of this from hog manure. Therefore, the MPC calculates: 14% x 15% x 55% = approximately 1%.

Unfortunately for the Pork Council, the Lake Winnipeg Stewardship Board itself refutes the MPC's fundamental assumption. At page 25 of its interim report, the board makes a point of stating that, in Manitoba, phosphorus in the form of synthetic fertilizer has been applied to land generally in balance with what crops use. Indeed, the data in the report actually show an overall net negative balance of phosphorus on lands fertilized with synthetic phosphorus.

This is not surprising because the high cost of synthetic fertilizer limits the amount that individual grain farmers can economically apply. What it means is that, at least in theory, province-wide synthetic fertilizer use is, on balance, contributing zero per cent.

If this is so, what then happens to the Pork Council's one per cent?

Obviously, manure's importance would increase and could actually contribute up to 100 per cent of the agricultural phosphorus making its way into Lake Winnipeg. Using this, the appropriate calculation would then be 14% (from all agricultural sources) x 100% (manure's contribution) x 55% (hog portion of all manure) = 7.7%.

Let us put this figure into perspective. According to Manitoba Water Stewardship, the nutrient crisis currently threatening Lake Winnipeg has resulted from a rise in the lake's phosphorus of just 10 per cent over the past 30 years. As with climate change, there is a tipping-point where even small amounts of added nutrients may provoke a cascade of problems, such as those we are witnessing in Lake Winnipeg.

The Lake Winnipeg Stewardship Board reports that of all the phosphorus entering Lake Winnipeg, most comes from out of province (the lake's watershed is huge) and from natural processes beyond our control. When we remove the sources of phosphorus from outside Manitoba from the equation, the hog industry's impact becomes more striking and significant. By looking at what is happening only in Manitoba, agriculture as a whole contributes 33.3 per cent of the phosphorus to Lake Winnipeg and the hog industry's share is 18.3 per cent.

Keep in mind that the Pork Council's estimation methodology is simplistic at best. There are many other factors such as manure spills, topography, soil texture and productivity that must be taken into account in any objective estimate.

Moreover, the MPC relies largely on averaged data from 1994 through 2001, collected prior to the massive expansion in the hog industry in Manitoba. Manitoba Water Stewardship's latest (2006) phosphorus estimate assigns to all of Manitoba's towns, cities and industrial activities combined -- everything we do besides agriculture -- just nine per cent of the phosphorus entering Lake Winnipeg. Agriculture's contribution is now estimated to be 15 per cent.

When taken together, this all means that the Pork Council's one per cent claim simply has no credibility. Indeed, if the one per cent illusion was fact, then why is the intensive livestock industry the only food production system that the government has had to regulate? Why has the hog industry been "singled out" for a pause and a Clean Environment Commission review?

Clearly, the province recognizes that over-applying nutrients on land is the key factor in increasing the potential for nutrients to move into water. Indeed, the stated objective of its Water Quality Management Zones proposal is "to protect water from nutrients that may arise from the over-application of fertilizers, animal manure, and municipal wastewater sludge to adjacent lands beyond the amounts reasonably required for the benefit of crops and other plants within the immediate growing season."

The City of Winnipeg has committed to cutting its share of phosphorus loading to Lake Winnipeg from six per cent to four per cent. What is the hog industry proposing to do to reduce its contribution, apart from asking for and successfully negotiating regulations that allow massive amounts of surplus nutrients to be applied to the land?

Clearly, the Manitoba Pork Council is trying to avoid public scrutiny of the industry with full-page ads insisting that "water quality is everyone's responsibility." They have conjured up the one per cent illusion to try to convince Manitobans that the hog industry's contribution is not significant enough to warrant any change in the industry's production practices or rates of expansion.

However, public relations campaigns do nothing to save our most precious public resource -- water -- from further degradation. Nature is speaking to us now more loudly than ever, and Nature never lies. But is anyone actually listening?

Alan Baron is co-chair of Citizens for the Responsible Application of Phosphorus. CRAP is a grassroots organization of rural and urban individuals, community groups and scientists formed to research and provide public comment on issues specific to the relationship between phosphorus land application and water quality in Manitoba.