Drain Tile Rules and Regulations
Drain tiles are a common management tool used to improve crop yields and soil conditions and to improve timeliness and accessibility for field operations in areas that are otherwise too wet. Agencies and entities that oversee a variety of drain tile regulations and rules include county zoning and county conservation offices, local drainage districts, the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS), the Wisconsin Department of Natural Resources (DNR) and the U.S. Army Corps of Engineers. We recommend a landowner or a landowner’s contractor contact each of these agencies prior to starting a project to ensure they are following all applicable rules and regulations. More information about agency drain tile regulations can be found below.
- Drain Tile Regulation Guide – UW Extension
- Guide to Decide Which Agency to Contact for Tile Projects – DNR
When To Contact Wisconsin DNR
Landowners or their contractors are encouraged to contact the DNR prior to beginning a drain tile project if they will be working in or adjacent to wetlands. The general location of mapped wetlands and potential wetland areas can be identified using the DNR Surface Water Data Viewer. If drain tile work is proposed in either a mapped wetland or a potential wetland area, a landowner or their contractor will need to gain proper approvals from the DNR or complete their project in a manner that does not require DNR approval. Note there are some wetland areas that are not mapped on the two layers in the Surface Water Data Viewer. To complete a map screening for a property, a landowner or their contractor can complete the steps in the linked guide below.
Landowners or their contractors who wish to discuss proposed drain tile projects with a DNR water management specialist can find county contacts at Waterways Contacts. When discussing a proposed drain tile project with DNR field staff, landowners or their contractors should be prepared to provide the following information.
- Proposed drain tile locations
- Proposed connection, vent or lift locations
- Proposed outlet locations
- A description of the installation and construction techniques that will be used for the project
Drain Tile Projects That Do Not Require DNR Approval
Not all drain tile-related projects that occur in wetlands require DNR approvals, but it is best practice to check with DNR prior to completing a drain tile-related activity that is located in or adjacent to wetland areas. If a landowner or their contractor has a good understanding of where wetlands are located on their property, they can typically complete the following drain tile activities without DNR approval.
Projects in non-wetland areas: Tile installation or excavation outside of a wetland area that is associated with tile connections, lifts, pumps or similar devices does not require DNR approvals. Even though an area may be mapped as a wetland or potential wetland area, a more thorough wetland determination may indicate the Surface Water Data Viewer mapping is inaccurate. There are multiple methods that a landowner or their contractor can use to determine accurate wetland boundaries. Not all methods are appropriate for every site and DNR field staff can provide a recommendation for the wetland determination method most appropriate for the site. If the wetland determination indicates that wetlands are not present, DNR approvals are not required.
Some agencies, such as NRCS, complete wetland determinations for reasons unrelated to verifying whether state wetland regulations are applicable. For this reason, landowners and their contractors are strongly encouraged to contact the DNR to determine whether the wetland determination that was completed on their site is appropriate for DNR decision-making purposes.
Replacement and repair: Replacing or repairing existing drain tile and related appurtenances, such as existing connections, vents and pumps, does not require a DNR approval. Existing drain tiles or existing appurtenances must be currently used to drain agricultural lands and replaced or repaired in the same general footprint and to the same grade, size, and depth.
No discharge of fill activities: Installing new drain tile using techniques such as vibratory plowing and knifing does not result in a discharge of fill material when done correctly. DNR field staff can provide guidance to the landowner or contractor regarding whether a proposed installation technique will require DNR approvals.
Drain Tile Projects That Require DNR Approval
Installation of drain tile in a wetland area that has not been previously tiled requires DNR approval if the project will result in a discharge of fill. The following are examples of drain tile activities that require DNR approval.
Excavation for new tile: If a landowner or their contractor proposes to complete grading, excavating, or backfilling within wetland areas to place new tile or to install new connections, vents, lifts, or pumps where they did not previously exist, DNR approvals are required.
Mechanized land clearing: If a landowner or their contractor proposes to mechanically clear land or complete other mechanical vegetation grubbing activities in a wetland as part of their drain tile project, DNR approvals are required.
