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3. Effect of Pollution on Recreational Use
5. Conservative Worst Case Pollution Impact
Does the increase in pollution in the Buffalo River watershed reduce recreational activities? If it does, we could estimate the amount of economic damage that the increases in pollution levels cause. We could then compare that amount to the economic benefit that the agribusinesses who do the polluting gain, and see if the net effect on the economy is positive or negative. Unfortunately, we cannot confidently state that pollution levels are directly reducing recreational use of the BNR. But we can look at the trends, and look at the probable effects of pollution, and roughly estimate the economic costs of pollution.
First, we present the trends in recreational use of the BNR, to get an overview of changes in various recreational activities over the years. Second, we present the trends in pollution levels over the years. Third, we correlate changes in pollution levels with changes in recreational use, to see how much recreation decreases as a result of pollution increasing. In all cases, we account for monthly patterns of use (per Figure 4.1) by subtracting out the monthly differences in usage. (In our regressions, we use "dummy variables" to "hold constant" monthly differences).
See Figure 4-1
Monthly Pattern of Recreational Visits to the BNR
(Average by Month from 1989 to 1993)
Trends in Recreational Use
We collated data for a five-year period on various forms of recreational
use of the BNR watershed. Figure 4.2 shows the annual visitation
over the years 1989 through 1993. Table
C-1 through C-6 show graphically and numerically the trend in
each form of recreation.
See Figure 4-2
Annual Visitation to the BNR from 1989 to 1993
We interpreted the number of recreational visits as a general measurement of recreational use of the BNR. It is not a summation of our later list of recreational uses, but a count of the total visitation, as measured by the NPS in their Monthly Public Use reports.
Finding 4.1.1: Total visitation is increasing by 46,000 per year.
BNR recreational use is growing by 45,500 recreational visits per year from the current level of 1,030,000 recreational visits per year, or an annual growth rate of 4.4%.
We calculated the growth in visitation via a standard regression analysis, holding months constant and ignoring all the pollution effects. The growth in visitation is statistically significant at the 93% confidence level, and is robust through all pollution regressions. This is counter to the oft-repeated anecdotal belief that BNR visitation is just holding steady.
We separated the recreational use into water-based recreation (boating and fishing), and land-based recreation (hiking and overnight stays). The trend over the study period for each recreational use is shown in Figure 4.3, which indicates each type of usage as a percent of the total visitation (to make the trends more apparent and to hold constant the annual fluctuations). Recreational usages are measured in "days per year," which means the combined total of the number of days of canoe rentals, for example, or the number of person-days spent hiking.
Finding 4.1.2: Water-based recreational usage is decreasing.
Boating is falling by about 5,400 days per year from an average
92,000 days/year,
and fishing is falling by about 1,200 days per year from an average
19,000 days/year.
We calculated the decrease in water-based recreational usage by standard regression analysis. The reduction in water-based recreation, however, is only statistically significant at the 69% confidence level for boating and the 75% confidence level for fishing. More confident estimates could be made if we collect more data in the future. The new Tyler Bend NPS facility (a visitor center and a boat launch) will probably add a lot of visitation as well as a significant amount of water-based recreational usage. Doing this same analysis in a few years would probably show an increase due to the new Tyler Bend facility, in absolute terms, but the data suggests a continuing shift in relative terms from water-based to land-based recreation. Anecdotally, concessionaires are aware of the shift away from water-based recreation and towards land-based recreation (discussed next).
Finding 4.1.3: Land-based recreation is increasing.
Overnight stays are increasing by 18,900 stays per year from an
average of 123,000,
and hiking days are increasing by 4,400 days per year from an
average of 31,000.
We base this finding on graphical evidence in Figure 4.3 (our regression trend is shown in Table C-2 and C-6, and numerically in Table E-4). We heard anecdotal support for this finding as well: "Hiking is growing, and growth continues in lodging," says Mike Mills, owner of the Buffalo Outdoor Center, which rents rustic cabins and hiking equipment, as well as canoes. In addition, land-based tourism in the BNR watershed has become a source of commercial income: "Farms are photo sites for tour buses," says Sid Lorentz of the Searcy/Baxter SCS, and Acting Chairman of Searcy Co. Cattlemen's Association. "Ecotourism" is reportedly enough of a buzzword that the Newton County Resources Council is planning "non-impact" eco-tours of the BNR and nearby forests.
The policy prescription from the shift from water-based recreation is to focus on land-based resources. Pristine forests will become as important as a pristine river, which implies that efforts should be directed towards protecting existing forested acreage, avoiding clear-cutting, and keeping larger continuous tracts of forested land. Ranches and farms can be part of the "recreational experience," as far as tourists are concerned, which increases their economic value.
Finding 4.1.4: Hunting and fishing are decreasing.
Hunting days are decreasing by 1,300 days from an average of 9,700
days per year,
& fishing days are decreasing by 1,200 days from an average
of 19,000 days per year.
We base this finding on graphical evidence in Figure 4.3, and on a regression analysis shown in Appendix C and Appendix E. This is bad news from a political perspective, because hunting and fishing organizations are strong players in Arkansas politics. Ducks Unlimited, a hunter's organization, has widespread membership, for example. Many members of the Ozark Society, ostensibly an environmental protection group, likely joined to protect their hunting and fishing in the BNR. While hunting and fishing are not directly in line with the Stewardship Foundation's environmental goals, we should remember the maxim that "the hunter is the environmentalist's best ally." We did not investigate the reasons that hunting has been decreasing, but the loss of hunting opportunities in the BNR might be an important tool for lobbying for conservation.
See Figure 4-3 "Trends in recreational uses for the period 1988 to 1993"
Trends in Pollution
This section will examine trends in pollution, based on data provided by the NPS, covering the years from 1988 to 1992. We investigated four different forms of pollution briefly described below:
Finding 4.2.1: Fecal coliform pollution is increasing,
while other forms of pollutants do not show any significant trend.
Fecal coliform has an upward trend for the period 1988 to 1992.
We quantify these trends in Tables D-1 through D-4, but the results all have only limited confidence. The National Park Service and the Soil Conservation Service are currently producing reports on this subject, and their data will be considerably more accurate than ours. We base our finding only on the graphical trends apparent in Figure 4-4 on the following page and on the regression data in Table E-4. We interpret the fecal coliform increase as a sign that cattle manure runoff is a growing problem.
Figure 4-4 compares each pollutant to its average over the five-year period of study. We scale the average so that each one equals 100, to make the trend more apparent, and because the numerical values of the pollutants are not directly comparable. The "FC > 500" category cuts off the extreme cases of fecal contamination. This data is discussed in greater detail in Appendix D. A tabular version of the numerical data for Figure 4-4 is included in Appendix D-2. Insert Table 4-4 here, "Trend in pollution measures for the period 1988 to 1992", document "BNR4.4- Pollution Chart".
Effect of Pollution on Recreational Use
We looked for correlations between each of the pollutants above with both of the water-based recreational activities and with overall recreational visitation. We found a statistically significant effect of pollution on fishing, and a less significant, but still fairly confident effect of pollution on both boating and total recreational visitation. In all cases, increasing pollution levels reduces the amount of recreational activity, but these are all just correlations, and do not necessarily imply a causative relationship.
We measure the effect of pollution on recreational use by calculating how much recreational activity would decrease if the average pollution level for the year were increased to the average pollution level in the worst month of the year. We call that the "plausible worst case" of pollution levels, because it represents a level of pollution which has already been measured, albeit under the worst conditions of the year. A complete discussion of our methodology, of the meaning of confidence levels, and a summary of the regression results, appears in Appendix E. The raw data and details of our regression analysis is available upon request but is not presented here.
Finding 4.3.1: Pollution could reduce visitation by 55,000 days/year.
Reducing dissolved oxygen content to its "plausible worst case" level would reduce overall visitation by 5%, with perhaps some effect from turbidity and fecal coliform.
Finding 4.3.2: Pollution could reduce boating by 11,000 days/year.
Reducing dissolved oxygen content to its "plausible worst case" level would reduce overall boating days by 12%, with perhaps some effect from turbidity .
We expected that turbidity and fecal coliform would have had a significant effect, because they are both readily-seen pollutants. Dissolved oxygen is seen only as increased algae content of the river. Nevertheless, D.O. has the most significant effect on both overall visitation and on boating. We interpret D.O. as corresponding to fertilizer runoff; F.C. as corresponding to cattle ranch runoff; and turbidity as corresponding to soil runoff from deforestation. To the extent that those correspondences are true, fertilizer runoff is the most significant in terms of pollutants' effects on boating and total recreational use of the BNR.
Finding 4.3.3: Pollution could reduce fishing by 11,000 days/year.
Changing turbidity & acidity to their "plausible worst case" would reduce fishing by 59%. Increasing turbidity would reduce fishing days by 7,300 days annually (a 39% loss). Decreasing pH would reduce fishing days by 3,900 days annually (a 21% loss).
The effect of turbidity on fishing is our only "statistically significant" correlation (that is, the only regression that has above a 95% confidence level). We can state with certainty that an increase in turbidity does have an effect on the amount of fishing on the BNR. To the extent that turbidity corresponds with deforestation, deforestation in the watershed reduces recreational fishing use of the BNR. Acidity increases (which are pH decreases) also reduce fishing, although this result is a little less confident than "statistically significant."
Economic Impact
The average recreational user of the BNR spends $162.24 per trip on travel, lodging, sustenance, and direct recreational expenses (from Appendix B.2.2, Three-county area Per-trip expenditures) . If all of the pollutants discussed in this section's Findings were to increase to their plausible worst-case levels, the annual loss to the economy would be $12.6 million.
Recreational Loss due to Pollution -- Table 4.5 Plausible Worst Case Recreational Avg. activity Decrease due to Percent loss Gross cost Pollution Activity 1989-1993 to plausible due to of recreation measure worst-case pollution loss Total 1,030,939 -55,155 -5.3% -$8,948,347 D.O. visitation Boating days 91,971 -11,012 -12.0% -$1,786,587 D.O. Fishing days 19,085 -7,354 -38.5% -$1,193,113 Turbidity Fishing days 19,085 -3,946 -20.7% -$640,199 pH Total -77,467 -$12,568,246
There are many caveats in this analysis. 1) We did not analyze if recreational users would switch from one form of recreation to another. If that were the case, then the loss in gross revenue would not be a loss, but only a transfer, say from canoe concessionaires to hiking concessionaires. 2) We did not analyze if the loss in recreational uses would all occur simultaneously. The total visitation loss would probably reflect, in part, the loss in boating days and fishing days. 3) These losses would only occur if the pollution levels were all to increase from their current averages to the level of the worst month (our "plausible worst case").
With those caveats in mind, we extend the economic impact to the other aspects of travel-based losses described in Appendix B-2. Specifically, we will extend the loss in recreational activity to apply to the average per-trip three-county travel-generated economic benefits, as described in Appendix B.2.2. As described in Appendix B.1, the per-trip averages are derived from the three-county area, to be consistent with our definition of the BNR, although much of the actual travel expenses are spent elsewhere in the Ozark region. For this analysis, however, the distinction is irrelevant, since the average per-trip values for the whole Ozark region are nearly identical to those for the three-county region. The total losses described here would be spread over the whole Ozark region, however, not just the three-county region.
Economic Loss due to Pollution -- Table 4.6 Plausible Worst Case Recreational Payroll Travel job State Tax Local Tax Pollution loss losses losses losses losses Per-trip $27.44 2.6 per 1000 $7.25 $1.43 average Visitation - DO -$1,513,477 -143 -$399,888 -$78,710 Boating - DO -$302,174 -29 -$79,840 -$15,715 Fishing -Turb. -$201,797 -19 -$53,318 -$10,495 Fishing - pH -$108,280 -10 -$28,610 -$5,631 Total -$2,125,728 -201 -$561,656 -$110,551
All of the losses described in Table 4.6 would be annual losses due to the increase in pollution levels from the current average to the plausible worst-case pollution levels. These losses represent all of the losses that we can state with reasonable statistical confidence would occur, if pollution levels were to increase. In summary, we present our findings on the overall economic impact of the potential increase in pollution levels.
Finding 4.4.1: Economic impact from a reduction of 77,000 recreational trips, as a result of BNR pollution increases from their current levels to their plausible worst-case levels:
1. A loss of $12.5 million in gross tourism revenues.
2. A loss of $2.1 million in gross tourism-based payroll.
3. A loss of 200 travel-related jobs in the Ozark region.
4. A loss of $560,000 in annual state tax revenue.
5. A loss of $110,000 in annual local tax revenue.
Conservative Possible Worst-Case Pollution Impact
We constructed a more conservative estimate of the economic impact of pollution increases, which we call the "possible worst case" (more likely than the "plausible worst case"). We looked at the worst January of the four-year period of study, then the worst February, and so on. Those twelve "worst months" were put into one "possible worst case" year, which was compared to the base case. The following findings indicate the expected economic impact which would occur if the pollution levels rose from their current levels to the "possible worst case." Note, once again, that these pollution levels are all actually recorded already -- we are observing what would occur if the worst recorded months all occurred in one year.
Finding 4.5.1: Pollution could reduce visitation by 33,000 days/year.
Reducing dissolved oxygen content to its "possible worst case" level would reduce overall visitation by 3%, with perhaps some effect from turbidity and fecal coliform.
Finding 4.5.2: Pollution could reduce boating by 6,500 days/year.
Reducing dissolved oxygen content to its "possible worst case" level would reduce overall boating days by 7%, with perhaps some effect from turbidity .
Finding 4.5.3: Pollution could reduce fishing by 4,500 days/year.
Changing turbidity & acidity to their "plausible worst case" would reduce fishing by 24%. Increasing turbidity would reduce fishing days by 3,000 days annually (a 16% loss). Decreasing pH would reduce fishing days by 1,500 days annually (an 8% loss).
Finding 4.5.4: Economic impact from a reduction of 44,000 recreational trips, as a result of BNR pollution increases from their current levels to their possible worst-case levels:
1. A loss of $7.1 million in gross tourism revenues.
2. A loss of $1.2 million in gross tourism-based payroll.
3. A loss of 110 travel-related jobs in the Ozark region.
4. A loss of $320,000 in annual state tax revenue.
5. A loss of $63,000 in annual local tax revenue.