By Mike Bryson
This Monday, January 6th, the US Army Corps of Engineers released a major report about the Asian Carp threat to Lake Michigan as part of their long-running Great Lakes and Mississippi River Interbasin Study. Years in the making, and following on the previously released study on the Asian Carp controversy and the prospect of separating the Great Lakes and Mississippi watersheds by the Great Lakes Alliance nearly two years ago, the Corps study is now open for public comment online and at several scheduled meetings in the lower Lake Michigan region.
As noted here on the GLMRIS website:
The GLMRIS Report presents the results of a multi-year study regarding the range of options and technologies available to prevent aquatic nuisance species (ANS) movement between the Great Lakes and Mississippi River basins through aquatic connections. Through a structured study process, USACE identified thirteen ANS of Concern established in one basin that posed a high or medium risk of adverse impacts by transfer and establishment in the opposite basin. USACE analyzed and evaluated available controls to address these ANS, and formulated alternatives specifically for the Chicago Area Waterway System (CAWS) with the goal of preventing ANS transfer between the two basins.
The report contains eight alternatives, each with concept-level design and cost information, and evaluates the potential of these alternatives to control the transfer of a variety of ANS. The options concentrate on the Chicago Area Waterway System (CAWS) and include a wide spectrum of alternatives ranging from the continuation of current activities to the complete separation of the Great Lakes and Mississippi River basins. The GLMRIS Report also includes an analysis of potential impacts to uses and users of the CAWS, and corresponding mitigation requirements for adverse impacts to functions such as flood-risk management, natural resources, water quality, and navigation.
The alternatives presented in the report include:
- Continuing current efforts (i.e., the electric barriers) with “No New Federal Action — Sustained Activities.”
- Nonstructural control technologies (i.e., education, monitoring, herbicides, ballast water management).
- A technology concept involving a specialized lock, lock channel, electric barriers and ANS treatment plants at two mid-system locations in the CAWS.
- A technology concept (CAWS buffer zone) using the same technologies as number 3, preventing downstream passage from Lake Michigan at five points and preventing upstream passage at a single point at Brandon Road Lock and Dam.
- Lakefront hydrologic separation with physical barriers separating the basins at four locations along the lakefront of Lake Michigan.
- Mid-system hydrologic separation with physical barriers separating the basins at two mid-system locations.
- A hybrid of technology and physical barriers at four mid-system locations, leaving the Cal-Sag channel open.
- A hybrid of technology and physical barriers at four mid-system locations, leaving the Chicago Sanitary and Ship Canal open.
The GLMRIS Report presents evaluation criteria to help readers distinguish among the alternatives. Evaluation criteria include design elements unique to each alternative such as initial or long-term operational costs and duration for implementation, as well as related qualitative features for each alternative, such as the magnitude of impact for existing waterway uses or relative effectiveness of preventing interbasin transfer.
Notably, the Corps’ 232-page report avoids recommending a single strategy for protecting the Great Lakes and its $7 billion fishing/recreation industry, and instead describes and assesses a range of alternatives, from relatively cheap and low-impact measures that basically maintain the hydrological status quo in the Chicago Region, to far-reaching changes that would ecologically separate the Chicago River from the Mississippi Basin and potentially cost up to $18 billion over 25 years.
Despite the engineering challenges in reworking the flow of waterways and the design of wastewater systems across the broad Chicago Region, which ecological re-separation of the watersheds would necessitate, the city is no stranger to such ambitious and large-scale endeavors. Such an effort was responsible for the reversal of the Chicago River back in 1900 with the opening of the Sanitary and Ship Canal, the main shipping route from the Mississippi to the Great Lakes which also is a superhighway for invasive species like Bighead and Silver Carp. Long touted as one of the world’s engineering marvels, the Canal aptly represents how the present biological threat posed by the voracious and prolific non-native carp species is actually a human-made problem rather than a “natural” crisis.
As confirmed by Richard Lanyon, former director of the Metropolitan Water Reclamation District of Greater Chicagoland, at an Oct. 2011 water symposium in Chicago, separating the Great Lakes and Mississippi River watershed is certainly feasible from a purely technical standpoint; the real challenge is finding the political will and financial means to implement such a project. The question, therefore, is not whether the Chicago Region can figure out a way to address the physical reality of an potential invasion by non-native Asian Carp. The questions are, rather, these:
- How much do citizens and government leaders value the ecological and economic sustainability of the Great Lakes, which comprise 18% of the world’s available surface fresh water?
- How can the various governments and agencies responsible for the health of Lake Michigan — the Army Corps, the MWRD, the city of Chicago, the state of Illinois, the many other Great Lakes states and provinces, and the federal governments of the US and Canada — work together to devise and fund a viable solution to this entirely human-made problem?
Time, and public input, will tell how the Asian Carp ecological controversy is addressed effectively with long-term sustainability in mind . . . or whether we keep treading water with band-aid measures while the carp continue to migrate toward the Great Lakes and throughout the Mississippi River basin.
Mike Bryson edits the SUST at RU Blog and is its primary contributor since June 2012. An Associate Professor of Humanities and Sustainability Studies at RU, Bryson’s courses include SUST 210 The Sustainable Future, 220 Water, 240 Waste, and 350 Service & Sustainability. He has presented talks on the Asian Carp controversy and water issues in Chicago at various professional conferences and public forums.