UM Researcher: Estimates of Recreational Use Values May Remain Stable Over Decades

November 27, 2017

MISSOULA – Recently published work by a cooperative team of researchers, including participants from the University of Montana and the USGS Grand Canyon Monitoring and Research Center, reports the economic value that private boaters of the Grand Canyon assigned to their recreational experience remained relatively stable between 1985 and 2015 when adjusted for inflation. But the larger finding of the study indicates that data from past high-quality user valuation studies can remain valid for as long as decades, reducing the need for resource managers to replicate studies when evaluating policy changes.

UM math Research Specialist Chris Neher was the lead author on the study, which replicated a 1985 survey of Grand Canyon boaters in 2015 to explore the stability of recreational value estimates over the past 30 years.

“Our study showed that when adjusted for changing price levels, whitewater boater recreational value per trip was remarkably stable across time for four separate hypothetical river flow levels,” Neher said. “This finding provides evidence to resource managers that high-quality nonmarket economic studies can in some cases be relied on for as long as decades, thus reducing the necessity of committing funding for study replication.”

Research to measure the value that recreationists place on their experiences in natural settings has developed rapidly over the past several decades. Resource managers in federal and state land management agencies rely on such research in order to fully and accurately evaluate the economic impacts of proposed policy changes on public lands, but high-quality original studies are expensive and time-consuming to conduct.

This research set out to answer a question resource managers often ask: Once a study of the recreational value of a specific use of a resource is conducted, how long can managers rely on that value estimate to be accurate and unchanged?

In the 1980s a suite of Colorado River user surveys was undertaken to estimate how different water levels in the Colorado River impacted the value that Grand Canyon whitewater boaters placed on their recreational river experience.

“While our study was intended to update the nearly 30-year-old Grand Canyon study boater valuation estimates, we also recognized the opportunity to test the temporal stability of recreational values from a high-profile, high-quality study over a period much longer than had been reported previously in the literature,” Neher said.

“In a time of scarce funding for original survey research associated with uses of federal and state natural resources, our findings, when properly applied, should provide an increased level of confidence to resource managers when relying on past valuation studies to evaluate current policy proposals,” Neher said.

The paper was published Nov. 7 in the journal Water Resources Research. It is online at


Contact: Chris Neher, research specialist, UM Department of Mathematics, 406-243-5569,