Economic Impacts of Zebra Mussels on Drinking Water Treatment and Electric Power Generation Facilities

Abstract

Invasions of nonnative species such as zebra mussels can have both ecological and economic consequences. The economic impacts of zebra mussels have not been examined in detail since the mid-1990s. The purpose of this study was to quantify the annual and cumulative economic impact of zebra mussels on surface water-dependent drinking water treatment and electric power generation facilities (where previous research indicated the greatest impacts). The study time frame was from the first full year after discovery in North America (Lake St. Clair, 1989) to the present (2004); the study area was throughout the mussels' North American range. A mail survey resulted in a response rate of 31% for electric power companies and 41% for drinking water treatment plants. Telephone interviews with a sample of nonrespondents assessed nonresponse bias; only one difference was found and adjusted for. Over one-third (37%) of surveyed facilities reported finding zebra mussels in the facility and almost half (45%) have initiated preventive measures to prevent zebra mussels from entering the facility operations. Almost all surveyed facilities (91%) with zebra mussels have used control or mitigation alternatives to remove or control zebra mussels. We estimated that 36% of surveyed facilities experienced an economic impact. Expanding the sample to the population of the study area, we estimated 267 million dollars (BCa 95% CI = 161 million dollars - 467 million dollars) in total economic costs for electric generation and water treatment facilities through late 2004, since 1989. Annual costs were greater (44,000 dollars/facility) during the early years of zebra mussel infestation than in recent years (30,000 dollars). As a result of this and other factors, early predictions of the ultimate costs of the zebra mussel invasion may have been excessive.

Sensitivity of native and non-native mollusc species to changing river water temperature and salinity

“…Rising water temperatures may lead to replacement of coldwater mollusc species by more thermophilic ones (Daufresne et al 2004), but the mechanisms that may explain this shift are not yet understood. As molluscs constitute a large share of the group of macroinvertebrate invaders (Karatayev et al 2009;Leuven et al 2009) and invasive, fouling molluscs have serious economic and ecological impacts (Connelly et al 2007;Pimentel et al 2005;Strayer 2010;Vanderploeg et al 2002), there is a particular need for knowledge on physiological tolerances of these species. Knowledge on facilitating or limiting factors for the establishment of non-native mollusc species could be helpful to predict future species replacements and to derive management options for invasive species.…”

What is Novel About Novel Ecosystems: Managing Change in an Ever-Changing World

“…Both of these mussel populations expand rapidly causing serious economic and ecological effects. Facilities that rely on water intake, such as dams, become clogged with these invasive mussel species, which leads to the need for removal strategies, with large economic cost (Connelly et al 2007). In addition to the monetary cost, they also cause major ecological effects by significantly reducing the biomass and production of edible primary producers.…”

Conservation Officers: A Force Multiplier for Homeland Security

“…Economic impacts of zebra mussels have not been examined in detail since the mid1990s, although predictions have ranged as high as $1 billion per year (Connelly et al, 2007;Pimentel, 2005). Moreover, the over-land transportation of boats, motors, and trailers poses one of the greatest risks for spreading zebra mussels as larger mussels can live out of water for up to three days.…”

“…Ecologists speculate the mussels will continue to spread into additional rivers and inland lakes that are currently uninfected but within range of the invasion based on environmental and geological variables. Connelly et al (2007) surveyed water treatment facilities within known zebra mussel range and reported that respondents thought zebra mussels had been in the facility for 6 months to 1 year before discovery; only 20% of responding facilities had preventative measures in place prior to the discovery of zebra mussels. Given the ecological and human dimensions of zebra mussel invasions and management, it is possible that zebra mussels appeared in the case study lake as part of the "natural" ecological invasion of mussels through the Midwest and that the officials were not aware of the mussel invasion because, like Connelly et al (2007) found, they were not actively looking for them.…”