INVESTIGATING THE FEASIBILITY OF RIVER RESTORATION AT ARGO POND ON THE HURON RIVER, ANN ARBOR, MICHIGAN By: Wendy M. Adams Meghan Cauzillo Kathleen Chiang Sara L. Deuling Attila Tislerics A project submitted in partial fulfillment of the requirements for the degree of Master of Science (Natural Resources and Environment) at the University of Michigan August 2004 Faculty Advisor: Associate Professor Gloria Helfand ABSTRACT People have long used dams and reservoirs to produce energy, store water, control floods, provide recreation, and spur economic development. Dams also have negative impacts on rivers, such as habitat damage and water shortages downstream. Across the country, state and federal agencies are examining dam removal as a means to restore the ecological integrity of rivers. Argo Dam on the Huron River in Ann Arbor, Michigan, has been identified by the state Department of Natural Resources as a candidate for removal and ecological restoration. For an informed decision to be made on removal, much research is necessary, including studies on hydrologic, ecologic, economic, and social impacts. Our project focused on the human aspects of this issue, with the goal of evaluating the political and economic feasibility of restoring the Argo area. This included identifying stakeholders and determining the value of the dam and pond for users and local residents. Our research methods included a mail survey, interviews, and literature review. We found that the Argo area, and the dam in particular, is not well known among Ann Arbor residents. Nonetheless, after a description of the tradeoffs involved, dam removal was generally supported by residents and the net willingness to pay for removal was approximately $20 per adult per year. Differences in perceptions about the Argo area varied by proximity to the dam with residents living no farther than one mile from the dam having more familiarity and experience with the site than the average Ann Arbor resident. Removal of Argo Dam is strongly opposed by the rowing community, Argo Pond’s most important recreational user group. Due in part to lack of funds, the Ann Arbor City government does not consider removal of Argo Dam to be a priority, but sedimentation and growth of aquatic plants in the pond will require modification of present usage and management practices in the relatively near future. Our client, the Huron River Watershed Council, plans to use our findings to augment ecological and other data that they are gathering to develop proposals for the future of Argo Pond and Dam. i Executive Summary INVESTIGATING THE FEASIBILITY OF RIVER RESTORATION AT ARGO POND ON THE HURON RIVER, ANN ARBOR, MICHIGAN INTRODUCTION In 1995, the Michigan Department of Natural Resources conducted an assessment of the Huron River and identified Argo Dam, along with other dams on the river, as a candidate for removal, as it no longer serves its original purpose of producing hydropower, and its removal could benefit the aquatic environment for this urban stretch of the Huron River (Hay- Chmielewski et al. 1995). In this study, we have examined the social, political, and economic feasibility of removing Argo Dam using stakeholder interviews, an economic analysis, and a mail-based survey. We sought to answer questions about the community’s knowledge and perceptions about the dam, the ways in which the community and various stakeholders use the site in its current configuration, the economic values of Argo Dam and Argo Pond as they currently exist, the public’s willingness to pay for dam removal or dam maintenance, and the process and players involved in decisions about the future of Argo Dam. BACKGROUND Argo Dam in Ann Arbor, Michigan, is one of nineteen dams that impound the main stem of the Huron River. Argo Dam is eighteen feet high and 1940 feet long; 190 feet are composed of the spillway gates and sluice gates, while 1750 feet are earthen embankment (City of Ann Arbor 1971). Argo Dam creates a 92-acre impoundment called Argo Pond, which extends approximately one mile upstream from the dam. The average depth of Argo Pond is ten feet (Barr Engineering Co. 2002). It was originally built to provide power to small mills and was converted hydropower in the early 20th century, but it has been deactivated since 1959. It is now owned by the City of Ann Arbor, and provides mainly recreational benefits associated with the pond and surrounding parkland. In recent decades, it has become apparent that Argo Dam and Pond produce ecological costs, which were not understood or considered at the time of construction. It presents a physical iii barrier to the movement of fish, mussels and other aquatic organisms, many species of which require migration as part of their life cycles. Eutrophication is accelerated in the pond; it offers very different habitat conditions from those that would otherwise be present. The water is warmer and less oxygenated than a free-flowing river. The impoundment reduces the velocity of the river, trapping nutrients which encourage plant growth and releasing sediment which, together with additional sediment from decaying plant material, buries the original bottom substrate habitat needed by many aquatic species. The operation of the dam’s gates alters the hydrology of the Huron River: the gates open and close rather abruptly, frequently sending large rushes of water downstream. This has a scouring effect along the banks and bottom of the river, increasing erosion and destroying fish nests. Steve Blumer, with the US Geological Survey (USGS), claims Argo Dam is one of the most extreme examples of dams negatively affecting a river’s natural hydrology (Blumer 2003). Removal of Argo Dam would transform a mile-long section of the river from a lake to a free- flowing, high-gradient river. Currently, every high gradient portion of the Huron River’s main stem is dammed from Commerce Township to Lake Erie (Hay-Chmielewski et al. 1995). This is not atypical; in the state of Michigan, dams impound ninety percent of high gradient rivers and one hundred percent of those flowing into the Great Lakes (Blumer 2003). If river restoration were pursued, Argo Pond would be drained, narrowing the river and likely returning its flow to the channel it occupied over a century ago (Riggs 2003). Much of the land that is currently submerged beneath Argo Pond would become available to the City of Ann Arbor for additional riparian parkland and natural areas (Miller 2003; Naud 2003). METHODS We used interviews, review of relevant documents and academic literature, and a mail-based survey to gather data for this project. Interviews took place in two phases: an initial series was used to gather background information and plan the survey, and a second series of interviews focused on the interests and perspectives of the various stakeholders. The survey gathered data on usage of and attitudes toward the Argo site. We also used the contingent valuation method to estimate the survey respondents’ willingness to pay either to keep or to remove Argo Dam. The survey sample was divided into two strata; 1000 recipients were selected from iv within one mile of the Argo site, and another 1000 were selected from the rest of the city of Ann Arbor. SURVEY RESULTS Our survey response rate was 49%. Demographically, our survey achieved a broad but not wholly representative sample of the Ann Arbor population. The most notable pattern was underrepresentation of younger, less educated, and lower-income individuals, particularly in the stratum drawn from within one mile of the Argo site. This area is heavily populated by students; due to their transience, relatively few students were included in the source lists from which our samples were drawn. Attitudes and Usage We estimated that 43% of the adult residents of the study area (approximately the city of Ann Arbor) visited the Argo area in the 12 months prior to the survey; almost 22% have never been to the Argo area and are not familiar with it. Residents throughout our study area use Argo Pond or the parks around it; we estimate that people who live more than one mile from the pond account for nearly half of the recreational activity occurrences at the site. The most popular activities at Argo were walking, running, and bicycling, with 53% of the surveyed residents participating; 5% or fewer of the study area residents fished, kayaked, rowed, or skied there. However, over 64% of the kayaking and over 95% of the rowing done by adults in our study area was done at Argo, suggesting that Argo is an important site for these activities. Respondents generally were supportive of parkland and open space. They felt more familiar with and favorable toward the parks around the pond than toward the pond and the dam itself. About 60% of respondents expressed opinions about the parks around Argo Pond; the remainder indicated they were neutral, didn’t know, or didn’t answer the question. In contrast, only about 44% and 35% of respondents expressed opinions about Argo Pond and Argo Dam, respectively. Of those who expressed opinions about the parks, 95% had favorable opinions. Seventy-three percent (73%) of respondents with opinions were favorable toward Argo Pond and were least favorable toward the pond’s water quality. Just 49% of those with opinions about the dam expressed favorable opinions. v In response to two questions asking whether Argo Dam should be removed or remain in place, about 60% of respondents indicated no preference; of those expressing a preference, small majorities favored keeping the dam. However, when later asked in a referendum format whether they supported dam removal at no cost to them, given only “Yes” or “No” alternatives, fewer than 7% gave no response, and 62% of those who responded indicated they would vote to remove the dam.