by Greg Brennan, IGS, Hydrogeologist

IGS Staff Group Photo 2021

What do you know about the Iowa Geological Survey? 

The Iowa Geological Survey (IGS) has a long and illustrious history in the state, beginning in 1855, when legislation proposed by Governor James W. Grimes provided for a geological survey of the state, which was led by State Geologist James Hall. It was the start of great things for the state of Iowa, with its many geological resources. Iowa established a permanent geological survey as a separate agency of state government in 1892 and appointed Professor Samuel Calvin, Chair of the Department of Geology at the University of Iowa, as the first State Geologist of the newly minted Iowa Geological Survey. For a full history read IGS History, Vol. I and IGS History, Vol. II.

In 2014, IGS merged into IIHR–Hydroscience & Engineering, within the College of Engineering at the University of Iowa. IIHR itself recently celebrated its 100th anniversary as a world-renowned center for education, research, and public service focusing on fluids. I encourage a visit to the Old Capitol Museum in Iowa City which is presently hosting the IIHR Centennial Exhibit – A River Flowed Through It: Iowa’s Legacy in Fluid Mechanics, or visit via the Virtual Tour at A River Flowed Through It.

IIHR and IGS together form an organization with expertise that now covers all aspects of Iowa’s hydrologic cycle — precipitation, evaporation and evapotranspiration, surface flow, infiltration, and groundwater flow within our state’s unique geologic framework. The IGS contributions of geology and groundwater are a valuable component, as Iowa’s groundwater network is a natural water storage and distribution system that provides drinking water for more than 80 percent of Iowa’s population and supports Iowa’s important agricultural economy. Over one hundred thousand wells across the state tap four major aquifers (Cambrian-Ordovician, Silurian-Devonian, Dakota, and Mississippian) and dozens of local aquifers to provide access to these groundwater resources. Quantifying and sustaining these aquifers is a crucial and continuing work of the IGS.

What can the Iowa Geological Survey tell you?

The IGS Mission is to collect, reposit, and interpret geologic and hydrogeologic data, to conduct foundational research, and to provide Iowans with the knowledge needed to effectively manage our natural resources for long-term sustainability and economic development. Toward this end, scores of geologists.  Toward that end, the following sources give access to a wealth of geoscience information and data:

Iowa Geospatial Data Geodata (

A repository for public geospatial data, tools, and resources from the State of Iowa. Data is organized into thematic categories, where IGS is primarily linked via the Geoscientific and Water collections.

Iowa Geological Survey IGS – Iowa Geological Survey

The IGS website offers access to a wide range of data and resources, research, services, and items of popular interest. We likely have what you are looking for. Whether you are interested in Geology Geology of Iowa, Landforms Landforms of Iowa, State Parks Parks of Iowa, Information Data and Publications, Current Research Research, or just the latest happenings available at What’s New at IGS and in our first class Annual Report Geode 2020.  Below are a few examples of available information from IGS and IIHR:

IGS Databases

  • IGS-Publications is the where IGS maintains a catalog providing information on the geological resources of Iowa, including groundwater, bedrock, glacial materials, and mineral resources.
  • IGS-GeoSam is Iowa’s geologic site and sample tracking program. GeoSam provides location, identification, and other key information about every available well, rock exposure, or site of geologic information in Iowa.
  • IGS-GeoCore tracks cores in the IGS’ Rock Library. GeoCore stores depth intervals, storage location, and high-resolution photographs for each core stored.
  • IGS-GeoLab showcases laboratory results from over 6,000 rock samples across Iowa. Results found in GeoLab include: grain size, radiocarbon dates, clay mineralogy, pXRF, soil carbon and nitrogen, matrix carbonate, bulk density, and clast lithology data.
  • IGS-Pump Test gives users electronic access to IGS’ collection of aquifer pumping test data and results. This information can be used to evaluate long term well yields, and to construct and calibrate groundwater flow models.

Tools of Interest

Samuel Calvin once remarked that “the Survey has earned its place as an important factor in contributing … to public education, helping the people to see and appreciate and correctly interpret the geological phenomena which lie all about them”.  Calvin’s well-articulated message, of responding to the state’s economic resource needs, with information based on scientific research and communicated effectively, is as valid today as it was more than 100 years ago

So, I invite you to follow us on Facebook Facebook – IGS, or Twitter Twitter – IGS, or give us a call (319-335-1575) to schedule a time to stop by and visit in person Visit Us – IGS, when a geologist would be happy to have a conversation on anything geology in keeping with the long and proud tradition of the Iowa Geological Survey.