COMMITTEE ON AGRICULTURE
U.S. HOUSE OF REPRESENTATIVES
June 28, 2000
Dr. Derek Winstanley
Chief, Illinois State Water Survey
I am pleased to have the opportunity to present to you, Mr. Chairman, and members of the Committee on Agriculture information on the status and trends of water quality in some of the nation's most important rivers.
My name is Derek Winstanley. I am Chief of the Illinois State Water Survey, which is a Division of the Office of Scientific Research and Analysis in the Illinois Department of Natural Resources. The Illinois State Water Survey is perhaps the largest and longest established scientific institution addressing water and atmospheric resources in any state in the nation. The Survey was founded in 1895 and has some unique and valuable data sets of direct relevance to the interests of the Committee.
A fundamental underpinning of my presentation is that sound policy, regulations, and resource management strategies should be based on the best available scientific information. As a scientist, I will focus my presentation on scientific data, analyses, and interpretations.
For the past three years, I have investigated historical trends in nitrogen concentrations in the Illinois River, the Mississippi River, and the Ohio River. I will present some of these data and explain their importance to the Committee.
Nitrogen is a nutrient whose richness in the landscape and loads in surface waters have changed over time as a result of natural and human influences. It is the loads of nitrogen and other chemical species that are the focus of this hearing. [Note: the load, or amount, of nitrogen carried by a river is determined by the concentration of nitrogen in the water times the amount of water discharged by the river. The amount of water discharged by a river is determined largely by the amount of rainfall.]
Nitrogen concentration and loads are of great concern and interest in Illinois for many reasons. In this presentation, I will focus on the issue of hypoxia in the northern Gulf of Mexico. Hypoxia, a depletion of dissolved oxygen in surface waters, affects coastal ecosystems.
The information I present is important not only in addressing the issue of hypoxia, but also in setting nutrient criteria and standards and in designating total maximum daily loads (TMDLs). In all these issues, accurate data are needed for nutrient concentrations and river flow. The United States Environmental Protection Agency plans to use reference/background conditions in establishing new nitrogen and phosphorous criteria and standards, and establishing historical water-quality conditions and understanding why conditions have changed over time will be of increasing importance.
But as the need for more data increases, the availability of data is decreasing. In Illinois, the number of flow gages in the Illinois Streamgaging Network has been reduced from 171 to 150 gages. On small agricultural watersheds best able to tell us the flow of nutrients from farms to rivers, the number of gages has declined from 45 in the 1960s to only 15 in FY2001.
Hypoxia in the Northern Gulf of Mexico and Nitrogen Sources in the Midwest
The federal Committee on Environment and Natural Resources (CENR) has recently conducted an assessment of the causes and consequences of hypoxia in the northern Gulf of Mexico. Earlier in June, the CENR released the final Integrated Assessment (CENR, 2000a) and a set of responses to public comments (CENR, 2000b). The stated purpose of the Integrated Assessment is to provide scientific information for an Action Plan later this year, as required in the Harmful Algal Bloom and Hypoxia Research and Control Act of 1998 (P.L. 105-383). The Integrated Assessment also addresses changes in nutrient concentrations and loads within the Mississippi River Basin (MRB) itself.
Below are some key findings of the Integrated Assessment that are of particular interest to me. I present these findings along a causal chain of reasoning, as depicted in Figure 1.
- Hypoxia has intensified only since the 1950s.
- Hypoxia is caused primarily by excess nitrogen delivered from the MRB, in combination with stratification of Gulf waters (Figure 1a).
- The concentration of nitrogen in the MRB prior to European settlement (pristine conditions) is estimated to have been 1.24 milligrams per liter (mg/l) and to have doubled in the last 100 years.
- The concentration and transport of nitrogen to the Gulf from the lower Mississippi River has almost tripled between the periods 1955-1970 and 1980-1996 (Figure 1b).
- The principal sources of nitrogen in the MRB are the river basins that drain the corn-soybean belt in southern Minnesota, Iowa, Illinois, Indiana, and Ohio. The Ohio and upper and middle Mississippi Rivers contribute about 90 percent of the nitrogen in the lower Mississippi River.
- The nitrate concentration trend in the Ohio River (Figure 1c) does not match the trend in the lower Mississippi River (Figure 1b). Therefore, the increasing trend of nitrate in the lower Mississippi River in the 1970s is assumed to be due to a large increase in nitrate concentration in the upper and middle Mississippi River.
- A 40 percent reduction in total nitrogen transport to the Gulf is necessary to return loads comparable to those during 1955-1970.
Before presenting additional data that paint a very different picture, I would like to point out some characteristics, strengths and limitations of the CENR reports, as I see them.
In all environmental issues, especially those where long-term trends are important, the issue of data quality is exceedingly important. The CENR addresses data quality briefly. It acknowledges changes in analytical methods since the 1950s, but concludes that these analyticalchanges have not contributed to trends in nitrogen concentrations. The data for the 1890s seem to have been accepted at face value.
The CENR also produced six peer-reviewed scientific reports in 1999 on various aspects of the hypoxia issue. In the Topic 3 report, "Fluxes and Sources of Nutrients in the Mississippi-Atchafalaya River Basin," the authors acknowledge that much more data exist, but have not been used: " A large body of additional data on nutrient concentrations is available from numerous State, local, and Federal agencies in the basin. However, these data were not used because of the short time frame for this analysis and the effort that would be required to obtain and quality assure the data to insure that sample collection and analytical methods were comparable with methods used by the USGS" (CENR, 2000a).
The only nitrogen concentration data presented by CENR for the lower Illinois River were for the periods 1897-1902 and 1980-1998. No data were presented for the almost 80 years between 1902 and 1980, although data do exist.
The CENR did not present any data on nitrogen concentration in the middle Mississippi River between St. Louis and the confluence with the Ohio River, although such data do exist.
Although CENR acknowledged "a direct relation between nitrate concentrations and streamflow," it also stated that "No attempt was made to determine streamflow conditions for the historical data" (Goolsby et al., 1999). Thus, CENR did not adjust historical nitrogen concentration trends for streamflow changes. This is a major shortcoming of the assessment. It leaves open the possibility that reported increases in nitrate concentrations and loads could be due significantly to natural increases in rainfall.
Scientists establish the credibility and reliability of their data through the peer-review process. The CENR reports were peer-reviewed and approved by the CENR, which has representatives from some 20 federal agencies.
During the public comment periods many comments on these reports were submitted. In its submission, Illinois included additional data on various forms of nitrogen concentrations in the Illinois and Mississippi Rivers, including nitrate. However, these data were not included in the Integrated Assessment and were not acknowledged in the CENR response to public comments.
Illinois State Water Survey water-quality data from the 1940s to the 1970s have been published and used extensively. For example, Barry Commoner, in his seminal 1970 presentation to the American Association for the Advancement of Science, reported that: "A particularly useful set of data is available on the nitrate content of the rivers of Illinois where for the last 25 years the Illinois State Water Survey has been making increasingly detailed studies of the quality of surface waters." And Professor M. Gordon Wolman published these same data in 1971 in an article on "The Nation's Rivers" in the nation's prestigious Science magazine.
I now would like to show the Committee my data for the Illinois River and explain the differences between my nitrogen concentration trends and those produced by CENR. I used the same data sources identified by CENR and additional data not used by CENR. I would also like to discuss some implications for Illinois of the these different trends.
Figure 1d shows a smoothed reconstruction of annual nitrogen concentrations in the lower Illinois River from 1894 to 1998. Total nitrogen concentration (top line) is the sum of four forms of nitrogen: ammonia-nitrogen, organic-nitrogen, nitrite-nitrogen, and nitrate-nitrogen. It can see from this figure that the concentration of total nitrogen in 1894-1899 was already 3.7 milligrams per liter (mg/l). The concentration increased to about 10.0 mg/l in the mid-20th Century and subsequently declined to 4.8 mg/l in 1993-1998. The concentration of nitrate reached 6.2 mg/l in 1967-1971 with a peak of 8.4 mg/l in 1971 (not evident in the smoothed data) - and declined to 3.8 mg/l in 1993-1998.
But nitrogen chemistry is extremely complex, and taking these data at face value does not allow a meaningful comparison between the concentrations at the start and end of the record. The concentration of nitrogen in Midwest rivers is, as CENR acknowledged, strongly influenced by rainfall and river flow: the higher the rainfall and river flow, the higher the concentration of nitrogen. The 1890s was a period of severe drought in Illinois and the last decades of the 20th Century were wet. In order to meaningfully compare the 1890s total nitrogen concentration data with the 1980-1998 data, I have applied corrections for river flow and measurement methods. Applying a river flow correction and a correction for the organic nitrogen contained in the microscopic organisms that were noted but not measured in the 1890s (indicated by "biota" in Figure 1d), I estimate that total nitrogen concentration in the lower Illinois River in 1894-1899 was 5.5 mg/l, i.e., higher than the current concentration of 4.8 mg/l.
The implications for Illinois of differences between the CENR and the above data are enormous.
According to the CENR data, a 40 percent reduction in nitrogen transport to the Gulf is necessary to return to loads comparable to those during 1955-1970. (Please be reminded that CENR provided no data for the Illinois River for the 1955-1970 period.) Figure 1d shows that the concentration of nitrate in the Illinois River in the 1990s has already returned to levels measured in the 1955-1970 period, i.e., 3.8 mg/l. The concentration of organic nitrogen and ammonia is now much lower than in 1955-70. Overall, the concentration of total nitrogen has decreased by about 50 percent since the 1955-70 period.
Thanks to major reductions in point and nonpoint source pollution, Illinois has already made major strides in cleaning up the Illinois River. The Illinois River today is less eutrophic (nutrient rich with junglelike vegetation) than it was in the 1800s and mid-20th Century, but CENR did not recognize the cleanup.
As the concentration of nitrate in the Illinois River decreased during the 1970s, I conclude that the Illinois River cannot have contributed to the increase in the concentration of nitrate that CENR reported for the lower Mississippi River during this period (Figure 1b). The trends were the opposite: as the concentration of nitrate in the Illinois River increased to a peak about 1970, the concentration of nitrate in the lower Mississippi River decreased; and as the concentration of nitrate in the Illinois River decreased after 1970, concentration of nitrate in the lower Mississippi River increased.
So, neither the Ohio River (Figure 1c) nor the Illinois River (Figure 1d) can account for the increasing nitrate trend reported in the lower Mississippi River during the 1970s (Figure 1b). Other data not shown here demonstrate that the concentration of nitrate in the middle Mississippi River peaked around 1970 and also did not increase in the 1970s. Thus, we are left without any explanation for the increase in nitrate concentration in the lower Mississippi River in the 1970s (Figure 1b).
Another perspective on these data is that a return to 1890s conditions would necessitate a return to highly eutrophic conditions, i.e., nutrient overenrichment with tropical vegetation. The CENR acknowledged that the Illinois River in the 1890s had a nitrogen concentration above 1.5 mg/l and was, by the threshold identified in the Integrated Assessment, highly eutrophic (overenriched with organic material and nutrients) more than 100 years ago, long before the widespread use of chemical nitrogen fertilizer.
The fact is that early travelers and settlers described the Illinois and Mississippi Rivers as already being nutrient overenriched and putrid (Krug and Winstanley, 2000). For example, Schoolcraft reported in 1821 that the water in the Mississippi River was so loaded with natural decaying organic matter that water samples could not be kept because the intense fermentation kept blowing off the corks on the collection bottles. The population of Illinois at this time was about 40,000.
And Charles Dickens, traveling on the Mississippi River along Illinois in 1842, described the river as, "An enormous ditch, sometimes two to three miles wide, running liquid mud, six miles an hour: its strong and frothy current choked and obstructed everywhere by huge logs and whole forest trees: now twining themselves together in great rafts, from the interstices of which a sedgy lazy foam works up, to float upon the water's to float upon the water's top...." "We drank the muddy water of this river while we were upon it. It is considered wholesome by the natives, and it is something more opaque than gruel."
Before concluding, I would like to make one final point, Mr. Chairman. The CENR identified the use of nitrogen fertilizer in the Midwest as one of the key causes of high nitrate concentration in the Illinois and Mississippi Rivers and hypoxia in the Gulf of Mexico. However, the data do not show a consistent relationship between nitrogen fertilizer use in Illinois and nitrate concentration in the lower Illinois River. The concentration of nitrate in the lower Illinois River increased rapidly from about 1945 to1970 (Figure 1d). This increase in nitrate concentration occurred at the same time that the use of nitrogen fertilizer in Illinois was increasing. Some 30 years ago, Barry Commoner used these Illinois State Water Survey data to firmly establish a so-called causal relationship between increasing fertilizer use and increasing nitrate concentrations in Midwest waters. However, this statistical relationship breaks down after about 1970. From 1970 to the early 1980s the use of nitrogen fertilizer increased by more than 400,000 tons per year in Illinois, but the concentration of nitrate in the Illinois River decreased.
The cause of a lack of a consistent relationship between nitrogen fertilizer use and nitrate concentration in the Illinois River needs to researched. Clearly, factors more dominant that fertilizer use have controlled nitrate concentration in the river. These factors include reductions in point-source inputs, reduction in nitrate loss from fields, and increased supply of dissolved oxygen necessary to transform organic nitrogen and ammonia into nitrate.
The CENR found that "Scientific uncertainty is a fundamental condition for most environmental policy making" and that "the need for additional science is unequivocally recognized." The CENR also recognizes that "The question, which has been strongly raised by several reviewers, is whether there is adequate understanding to proceed and how far we should proceed."
The CENR response to these concerns was that "The rigorous technical peer-review process that the six Topic reports underwent assures that the information they contain is well founded and grounded in available research and monitoring data, and that they provide a suitable basis for development of an Action Plan" (CENR, 2000b)
I believe, Mr. Chairman, that the concerns that I have raised relating to the availability, use, credibility, and reliability of data are the same concerns that you are raising on the issue of TMDLs. In the case of the hypoxia Integrated Assessment, the best scientific information has not been used, despite peer-review and approval by some 20 federal agencies. Determining whether we have a sound scientific basis for decision making goes beyond science, and I respectfully defer this determination to risk managers and decision makers.
I am greatly disappointed and frustrated, Mr.Chairman, that the federal government has not found the time in a three year national science assessment to locate and use all relevant data. What is even more frustrating is that they have ignored data that have been provided to them. Why should we encourage our children to become scientists when scientists are ignored?
My data and analysis, Mr. Chairman, leads me to four major scientific conclusions:.
1. By not using all available data, CENR has mischaracterized water-quality conditions in the Illinois River in pre-European-settlement times and in the 20th Century. The Illinois River is today less nitrogen rich than in the 1800s.
2. The CENR presents no historical data to identify the source(s) of the increase in nitrate concentration reported for the lower Mississippi River during the 1970s, which is at the heart of the hypoxia assessment findings. According to the data I have presented, Illinois certainly did not contribute to this increase.
3. The data do not show a consistent relationship between fertilizer use in Illinois and nitrate concentration in the lower Illinois River.
4. The CENR causal chain of reasoning connecting corn-soybean agricultural practices in the Midwest to an increased concentration and flux of nitrogen from the lower Mississippi River to the Gulf of Mexico is broken.
Where should we go from here? In my view, we need to undertake a major effort to characterize the status and trends of the nation's rivers. This would entail five major components: i) search out all the available historical water-quality data, ii) assure the quality of the data, with confidence levels, iii) correct the data for variations in rainfall, river flow, plant-life, and other changes in the landscape and aquatic systems that affect nitrogen concentrations, iv) analyze the data for trends, and v) seek to explain these trends. We also need to design and put in place a suitable monitoring network to evaluate the status and trends of water quality and quantity in the nation's rivers and streams. The data and information that would be forthcoming from such efforts would provide an improved scientific basis for addressing related issues such as water-use impairments, nutrient criteria and standards, and TMDLs.
The need for better scientific data is not new. In his article on "The Nation's Rivers" published in Science magazine in 1971, Professor M. Gordon Wolman identified the same problems and solutions to appraising trends in water and river quality. In 1992, a report of the United States Environmental Protection Agency by Professor Stephen B. Lovejoy on "Sources and Quantities of Nutrients Entering the Gulf of Mexico from Surface Waters of the United States" concluded that "One major finding of this study is the poor quality of the data upon which to base decisions about protection of the water of the Gulf of Mexico."
While a sound scientific basis for environmental protection and restoration is being developed, it is important to acknowledge and fully fund existing programs that have proven to be successful in monitoring the quantity and quality of our nation's waters and in reducing nutrient loads, e.g., Environmental Quality Enhancement Program, Conservation Reserve Program, Wetland Reserve Program, Wildlife Habitat Incentives Program, and Conservation Practices Program. Landowners and farmers also have adopted best management practices and conservation programs and engage in partnerships with state and federal agencies.
Thank you Mr. Chairman and members of the Committee for providing the opportunity for me to present this information.
CENR. 2000a. "Integrated Assessment of Hypoxia in the Northern Gulf of Mexico." National Science and Technology Council Committee on Environment and Natural Resources, Washington, D.C., June 2000.
CENR. 2000b. "Hypoxia in the Northern Gulf of Mexico - Responses to Public Comments". National Science and Technology Council Committee on Environment and Natural Resources, Washington, D.C., June 2000.
Commoner, B. 1970. "Threats to the integrity of the nitrogen-cycle: Nitrogen compounds in soil, water, atmosphere and precipitation." Global Effects of Environmental Pollution, S.F. Singer (ed.). A Symposium Organized by the American Association for the Advancement of Science held in Dallas, Texas, December 1968. Springer-Verlag, New York, pp. 70-95.
Goolsby, D. et al. 1999. Topic Report 3, "Flux and Sources of Nutrients in the Mississippi-Atchafalaya River Basin." National Science and Technology Council Committee on Environment and Natural Resources, Washington, D.C., May 1999.
Krug, E.C. and Winstanley, D. 2000. "A Contribution to the Characterization of Illinois Reference/Background Conditions for Setting Nitrogen Criteria for Surface Waters in Illinois." Illinois State Water Survey Contract Report 2000-08, Champaign, IL, June 2000.
Lovejoy, S.B. 1992. "Sources and Quantities of Nutrients Entering the Gulf of Mexico from Surface Waters of the United States." USEPA, Office of Water, Gulf of Mexico Program, EPA 800-R-92-002, Stennis Space Center, MS, September 1992.
Wolman, M.G. 1971. "The Nation's Rivers." Science 174:905-918.
B.A., M.A. (Geography); Ph.D. (Climatology) Oxford University.
Chief, Illinois State Water Survey (Illinois Department of Natural Resources) and Adjunct Professor of Geography, University of Illinois.
Direct atmospheric, surface-water, and ground-water research and service activities, and administer the Water Survey.
Deputy Chief Scientist, National Oceanic and Atmospheric Administration.
Assist the Chief Scientist (a political appointee) in oversight of NOAA's scientific research, monitoring, and service activities in weather and climate forecasting, marine fisheries, satellite operations, coastal and ocean studies, and navigation.
Director, National Acid Precipitation Assessment Program.
Direct and coordinate from the Council on Environmental Quality in the White House a multi-agency research and assessment program on the cause and effects of acid rain and its control. Focus on nitrogen and sulfur emissions, effects, and control.
United Nations; Canadian International Development Agency, Environment Canada, British Trust for Ornithology.
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