Big Ten Academic Alliance Geospatial Discovery Portal

Big Ten Academic Alliance Geoportal

Agricultural Drainage Wells: Iowa

Description:
This geospatial shapefile depicts the locations, functionality, owners and other observered characteristics of Agricultural Drainage Wells in the State of Iowa.<br /> Agricultural drainage wells are required to be registered both with the Iowa Department of Natural Resources as a part of the 1987 Groundwater Protection Act, and with the U.S. Environmental Protection Agency as a part of the Underground Injection Control Program. Subsequent to this amendment to Iowa Code, Senate File 473 was passed in 1997. The bill required "owners or agricultural drainage wells to prevent surface water intake into the wells, provided for the closure of certain wells and the construction of alternative drainage systems, provided state assistance for closing agricultural drainage well, prohibited the construction and use of certain structures located in agricultural drainage well areas, provided for the assessment and collection of certain drainage district expenses, provided penalties, and provided an effective date" for closures. This date was originally set as December 31, 1999 but was later amended to December 31, 2001. In 1998, following this legislation, ADW locations were computed from legal descriptions available and by hand drawn locations on section maps. The Iowa Department of Agriculture and Land Stewardship performed field checking of the location and function of each ADW registered and developed a database from this information. This information was used to create the original version of the shapefile "ag_drain_well". During the regulatory processes that led up to December 31, 2001, it was determined by EPA, IDALS, and IDNR that certain ADWs would be temporarily allowed to remain "unclosed" if it could be proven by landowners that no surface water could enter and drain through their ADWs. Landowners were required to apply for a temporary (valid for 10 years) "Continued Water Use Permit" in which they described the physical characteristics and condition of the ADW and their drainage areas (<a href="http://extension.agron.iastate.edu/Waterquality/adwfiles/adwform2.pdf">http://extension.agron.iastate.edu/Waterquality/adwfiles/adwform2.pdf</a> ). The information recorded in these individual Continued Water Use Permits were then distilled into a master ADW EXCEL spreadsheet and updated as needed. In 2008, as many of the continued water use permits approached expiration the IDNR and IDALS desired an updated version of the original ADW shapefile. The resulting updated ADW shapefile would be utilized to field check ADWs by IDNR Field Office Personnel in the winter of 2008 through the spring of 2009 to verify that active (i.e. not closed) ADWs were in compliance with State and Federal rules. An updated ADW shapefile was therefore created utilizing information from the abovementioned master ADW EXCEL file, Continued Water Use Permit Applications, and 1998 ADW shapefile. These data sources were aggregated to produce most of the attribute information. At the same time, locational information in this revised ADW shapefile was improved with the aid of sketches on aerial photo photocopies. These rough approximations of ADW locations were not available during the development of the 1998 ADW shapefile; they were created a year later by landowners while applying for Continued Water Use Permits. Utilizing these landowner sketches, the positions of active ADWs were compared to late 1930s, early 1990s, 2002, and 2006 orthophotography and repositioned (closed and reclassified ADWs were largely excluded from this revision). Additionally, some sites were further refined utilizing LiDAR elevational datasets. This second-generation GIS file was stored as an ESRI point shapefile called "ag_drainage_wells.shp", Edition 20080908. Using the 20080908 Edition of the ADW shapefile, Field Office Personnel carried out their field checks of active ADWs in the winter of 2008 through the spring of 2009. Compliance issues, the condition as well as the status of the wells (closed, fully functioning, etc.) were noted by Field Office Staff and entered into the master ADW EXCEL spreadsheet. This edition of "ag_drainage_wells.shp" (Edition 20091104) incorporates the Field Office staffs' observations pertaining to active ADWs that were recorded over the course of 2008-09.
Collection:
Iowa GeoData
Place:
Iowa, United States
Subject:
Utilities and Communication
Contributed by:
Iowa
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