Summary Paper


The Great Lakes Geologic Mapping Coalition was established in 1997 by the Illinois, Indiana, Ohio, and Michigan State Geological Surveys, in partnership with the U.S. Geological Survey. In January 2008 the Coalition expanded to include State Geological Surveys of Minnesota, Wisconsin, Pennsylvania, and New York. The Coalition's mission is making three-dimensional (3D) geologic maps of near-surface deposits to depths of several hundred feet at a scale usable for decision-makers to provide scientific facts required by developers and planners. Maps support: (1) cost-effective economic development decisions, (2) enhanced groundwater availability for residential, municipal, industrial, and energy consumption, (3) avoidance of areas where groundwater is susceptible to contamination, (4) identification of terrain where natural hazards may occur (such as loose soils that enhance earthquake shaking), (5) areas subject to erosion, flooding, or subsidence, (6) accurate inventories of sand and gravel for infrastructure development, (7) preservation and restoration of wetlands, (8) safe redevelopment of abandoned industrial lands, (9) siting of manufacturing enterprises, and (10) new or expanded waste disposal facilities. Mapping is conducted where it is most needed in urban/suburban areas, transportation corridors, regions with known environmental and homeland security risks, and areas of high water demand.


Public forums hosted by the Coalition in Indianapolis, Columbus, Chicago, and Peoria solicited input from constituent groups and demonstrated unanimous support for the program. Each was attended by more than hundred non-geologists who use geologic maps to make land management, public health, and economic development decisions. In addition, hundreds of support letters have been submitted to Congressional offices over the past few years from municipal, county, state, and federal offices and agencies, economic development groups, educational institutions, environmental groups, geotechnical consulting firms, industry, private consulting geologists, professional associations, soil and water conservation districts, and state and local political office holders.


A rigorous economic assessment of the only completed statewide mapping of this type was conducted for Kentucky. Using very conservative assumptions, two professional economists published a critically reviewed report concluding a return of $25 to $39 for each federal and state dollar invested in geological mapping. Furthermore, the Kentucky maps, completed originally to boost the mineral and energy industries, at a cost of more than $116M (year 2011 dollars), have been used primarily to address water supply and protection issues, growth, development, environmental problems, and mitigation of a variety of natural hazards.

Millions of tax dollars are spent every year to correct mistakes that could have been avoided had geologic maps been available. A spectacular example of the penalty the public pays for the lack of 3D geological maps is the failed attempt to site a low-level radioactive waste repository in Illinois. Unforeseen buried aquifers at a chosen site resulted in more than $85M being spent for site characterization before the site was recognized as unsuitable for disposal. Availability of 3D geologic maps would have eliminated the site earlier in the process.

Finally, recent efforts in Coalition states to locate CO2 sequestration sites, ethanol production plants, peaker power plants, and other high water-use industries are dependent upon knowledge of the 3D geology and the availability of large amounts of water, contained within the geology, needed to sustain them. Since about 80% of consumed water in the region is for energy production, there is an immediate need for this information, and it places an even greater responsibility on Coalition members to identify the resources and determine their long-term sustainability.


Beginning in FY2000, the program (in the USGS' National Cooperative Geologic Mapping Program) was a $500,000 line item in the Federal Budget, and from 2004–08, it was in the President's Budget. In the FY2009 President's Budget request, the $500,000 was removed, then restored by Congress and increased to $750,000.

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