Friday, July 29, 2016

The $294 Billion Dollar Question: Does Federal Farm Conservation Spending Work?

Farmers and other resource managers have long understood the negative consequences of soil erosion. Our government has also recognized that it is in the common good to reduce erosion to prevent and mitigate its consequences on water quality. Adjusted to 2009 dollars, the U.S. government spent $294 billion dollars between 1937 and 2009 with the goal of reducing soil erosion and sediment leaving the land and fouling our lakes and rivers (1). More than $500 per every U.S. citizen that has lived since 1937 has been spent trying arrest this problem. Did it work? (Spoiler alert: yes, but read on for details if you have time).

No-till farming. Lars Ploughmann photo
No-till farming. Lars Ploughmann photo

Farm revenue losses linked to reduced land value, lost nutrients and soil organic matter and reduced productive capacity can exceed $3000 per acre (2). Soil erosion also has societal costs linked to reduced reservoir storage capacity, diminished value of commercial fisheries, increased costs for navigation and degraded aesthetic and recreational value of lakes and streams.

In 1936 the U.S. Government began providing resources to farmers to correct the problem. These funds were first distributed through the old Soil Conservation Service headed by the legendary Hugh Hammond Bennett. Bennett’s vision helped focus American farmers on soil conservation. Through him they learned new cultivation strategies that conserved soil and its productive capacity. Bennett educated the public and elected leaders on this problem, which had national consequences in the 1930s. Later on, Congress appropriated money through the Natural Resources Conservation Service (NRCS) and Farm Service Agency (FSA) to address soil erosion. This money can be categorized in two basic ways: Technical Assistance (TA) which includes expert advice and administrative support needed to assist farmers with the planning and design work needed for implementation; and Financial Assistance (FA) that provides monetary incentives for adoption or land retirement. Over the course of the last 80 years, approximately 26% of these funds were allotted for TA and 74% for FA.

Time series plot graph of sediment in the Raccoon River
Time series plots of total suspended sediment (Panel A) and sediment load (Panel B) in the Raccoon River at Van Meter.

By the 1960s, many thought that conditions had improved, and research from Iowa and other places seemed to show that upland erosion had indeed declined (3). A recent Iowa study has shown that sediment loss has been significantly reduced since the 1970s (4). But definitively linking water quality improvements such as these to policy decisions is extremely difficult. A recent statistical analysis (5) by my colleague Gabriele Villarini, however, comparing sediment data from the most recent Iowa study with precipitation and TA and FA dollars since 1937 provides us with some good news.

It turns out trends in annual sediment loads (total amount transported by river) correlate as expected with all three variables: precipitation, TA and FA. More rain and more river flow produced more sediment loading; more TA and FA produced less sediment loading. But suspended solids concentrations (amount of sediment per unit volume of river water) depended not at all on rainfall, but only on TA and FA. One way to think about it is this: lots of rain produces a lot of muddy water and a little rain produces a little muddy water. But TA and FA both reduce the amount of mud in the water, no matter how much it rains. They both work as intended.

Which one works better? Remember that historically, only about $1 of TA is spent for every $3 of FA. It turns out the statistical models show that TA correlates far better with suspended solids concentrations than does FA. If we could turn back the clock, focus our conservation dollars on TA, and invest those funds at 2009 levels throughout the period of record (1937-present), suspended solids concentrations and loads would have been far lower than what they were, particularly in the 1940s and 1970s. Thus it seems it’s not all science and engineering. The human component of conservation delivery and implementation matters. If we wish to improve water quality and the resilience of our conservation systems, we must be willing to make investments not only in infrastructure, but also relationships.


(1) Pavelis, G.A., D. Helms, and S. Stalcup, Soil and Water Conservation Expenditures by USDA Agencies, 1935–2010 Historical Insights Number 10 (Washington, D. C.: Ecological Sciences Division, Natural Resources Conservation Service 2011).

(2) Duffy, M. Value of soil erosion to the landowner. Iowa State University Extension Publication A1-75. Iowa State University, Ames, IA.

(3) Piest, R.F. and R.G. Spomer. 1968. Sheet and gully erosion in the Missouri Valley loessal region. American Society of Agricultural Engineers Transactions. 11:850-853.

(4) Jones, C.S., and K.E. Schilling. 2011. From agricultural intensification to conservation: Sediment transport in the Raccoon River, Iowa, 1916–2009, Journal of Environmental Quality, 40: 1911-1923.

(5) Villarini, G.V., K.E. Schilling and C.S. Jones. 2016. Assessing the relation of USDA conservation expenditures to suspended sediment reductions in an Iowa watershed. Journal of Environmental Management, 180: 375-383.