Beneath Iowa's land surface is a vast, natural storage and distribution system for
groundwater, a resource that supplies over 80% of Iowans with their drinking water
supplies. This resource is available through wells drilled into river valley sands and
gravels, into other sand and gravel bodies buried within glacial deposits, and into the
deeper limestone and sandstone strata beneath the state.
Over 35,000 sets of samples have been collected from the state's well drillers and
contractors. These samples form a valuable "library" and are the basis of much
of our understanding of Iowa's subsurface geologic and hydrologic setting. Thousands of
logs prepared from these samples are available in our office or via electronic databases.
The Iowa Geological & Water Survey provides information on the availability of groundwater
supplies statewide. Given a specific geographic location, a water-well forecast
can be prepared summarizing the available groundwater sources, the
anticipated yields from existing aquifers, the quality of the water supply, the sequence
of geologic materials to be encountered in drilling, and appropriate advisories on well
construction or potential contamination problems. This information can be obtained by
letter or office visit, over the phone, or by electronic pathways.
Link to more information on:
Private Well Construction
The Iowa Department of Natural Resources and the Well Contractors Council
consumer information booklet that contains information regarding well
construction, well maintenance, well plugging, pump services, and Iowa
groundwater laws. According to Iowa law, this booklet shall be supplied by
certified well contractors at no cost to potential customers prior to the
initiation of well services. The cost of this booklet is paid for by private
water well construction permit fees.
Most of the information available on the natural water quality of Iowa's groundwater
concerns major chemical constituents, such as dissolved solids, hardness, and major ions
such as sulfate, sodium, and iron. Over the past decade additional information has become
available on water quality related to agricultural contaminants such as nitrate and
pesticides. Less information is available on trace metals, radionuclides, and organic chemicals.
Information on the water quality of the major aquifers can be found in many of our
publications, and individual
analyses from municipal wells can also be obtained.
Link to more information on:
Iowa's Municipal Water-Supply Inventory (MWSI)
Regional and County Groundwater Resources
Water Quality and Agriculture
Water wells are a fact of life for rural dwellers, municipalities, and industrial users
in Iowa. With thousands of well records from across the state on file, the Geological
& Water Survey can forecast geologic and hydrologic conditions for people needing to drill a new
well or needing to solve problems such as loss of yield or changes in water quality in
existing wells. Problems in individual wells depend not only on the natural water quality
of the aquifer, but on well siting, construction, and well history. For further
information, contact the Iowa Geological & Water Survey at 319-335-1575.
Additional advice on water quality problems can be obtained from the University of Iowa
Hygienic Laboratory at 319-335-4500. They have a variety of publications on water quality
and treatment. Another source is the Iowa State University Cooperative Extension Service
Office (515-294-4576) which also has publications on water quality problems and their
Catalog of Water-Well Databases
The Iowa Geological & Water Survey (IGWS) maintains an extensive collection of data
Natural Resources Geographic Information Systems Library which can
be used to evaluate water resources and environmental impacts to water resources in Iowa.
As with most organizations that deal with large quantities of information, we are making
the transition to electronic data management. During this transition, databases that were
formerly managed as paper files are being converted to electronic files. Substantial
overlaps may occur between the contents of various databases. We are working
to resolve these overlaps and potential conflicts, but this is a very large,