Geothermal Heat Exchange Wells and Ground-source Heat Loop Boreholes
Iowa requires that a water well construction permit be issued for all ground-source heat exchange loop boreholes installations (also known as GHEX or geothermal loop systems) before any construction takes place. These systems are commonly used for comfort heating and cooling for homes, businesses, and governmental buildings. In addition, the law requires that at least one Iowa DNR certified well driller be on-site at all times well services are taking place. Additional general information can be found at: www.iowadnr.gov/geothermalwells.
Code Citation 455B.172, 455B.187, 455B.190A, 567 IAC Chapter 49
Who Applies The application can be completed and submitted by the property owner or an agent for the property owner.
When To Apply Apply at least 72 hours before any drilling activity is planned for residential/home ground heat exchangers – ie. less than 10 boreholes. For commercial heat exchangers, a longer notice is required to allow for adequate environmental review. Please note that commercial systems that contain many boreholes require a Phase 1 type pre-drilling site audit to determine that drilling area is subject to any environmental covenants or contaminated sites. In addition, some local county governments may have longer waiting periods before a permit can be issued.
Initial Requirements Completed well construction application form 542-0988 is required along with the correct application fees for both local and state construction permits. Submit application and fees to your local county environmental health office. A list of these offices can be found at the following link: https://docs.google.com/spreadsheets/d/e/2PACX-1vSN9_vM3stj69X3-4qojMfxrkIGuP4dkCfZYo1DI9g8FSyJrs4SbfRYuDRPulMxStPClHPxdB1io1GR/pubhtml. Inquire at your local county for the appropriate application form and the local county permit fees. A permit to construct a test borehole cannot be used to construct the production loop field. Additional permitting is required. Contractors must be certified by the Iowa DNR to legally perform all well and geothermal borehole drilling services. In addition, the certified driller must be on-site and in direct control of the drilling services during all construction. Separate construction permits are required for test boreholes and the production borehole/well field. Please note that not all sites will be able to support geothermal boreholes/wells due to potential issues with local site or groundwater contamination. Start the permitting process early to minimize permitting delays.
Duration A construction permit for heat exchange loops or pump and reinjection wells is valid for a period of one year from the date the permit is issued.
Processing Time 2-4 days for normal household heat exchanger installations. Larger commercial loop fields may take substantially longer because they require additional investigation to ensure that the multiple boreholes do not interfere with any local areas of contamination or drinking water aquifers.
Fee Structure Construction permitting fees include a local county permit fee set by the county the borehole construction will take place in, and a $25 state well tracking system permit fee that is paid to the Iowa DNR. Please contact your local county well permitting authority for additional information. County Sanitarian Contact List: https://docs.google.com/spreadsheets/d/e/2PACX-1vSN9_vM3stj69X3-4qojMfxrkIGuP4dkCfZYo1DI9g8FSyJrs4SbfRYuDRPulMxStPClHPxdB1io1GR/pubhtml
Renewal Requirements Does not pertain.
Exam Does not pertain.
Additional Information See general website at www.iowadnr.gov/geothermalwells.
- Service SubCategory