Inventories and Maps

Green wetland with trees and white flowers

Wetlands, rivers, lakes, streams, and other types of waters across Oregon are protected by state and federal law so these resources can continue to provide important environmental and societal benefits. Projects that add, remove, or move material in wetlands or waters (including those on private land) may require a delineation report to identify resource boundaries. If the project cannot avoid wetlands and waters then a removal-fill permit may be required to document and mitigate any potential resource impacts.

Viewing an inventory is the start of a process to determine whether wetlands or waters may be present on a planned project site.

Steps to View Inventories and Maps

For more detailed instructions, see the how to use the SWI and next steps guide.

Start by looking at the Statewide Wetlands Inventory (SWI) web map. Zoom in to the site location or enter the address in the search bar.
The map may show:

The site is within a Local Wetlands Inventory (LWI) study area. Find the map of your area in the LWI list below.
The site is outside an LWI and wetlands, waters, or soils are mapped. Waters may also be mapped as essential salmonid habitat or a State Scenic Waterway.

If the SWI or LWI maps indicate there may be wetlands or waters, or soils that suggest the presence of wetlands or waters, the Department of State Lands can make a free preliminary determination, as capacity allows, of whether these resources may be present on your site and if a removal-fill permit may be needed.
If DSL staff determine wetlands or waters may be present, you will need to work with a professional consultant to delineate the boundaries of these resources.

Statewide Wetlands Inventory Map

DSL maintains a Statewide Wetlands Inventory web map that displays the approximate locations of wetlands and waters throughout Oregon. The map also shows areas where soil is likely to be wetter longer, indicating there may be unmapped wetlands present. SWI web map data sources are described in detail in the SWI map limitations document. Site determinations and delineations are part of the SWI but are not available digitally.

Map Resources:
How to use the SWI and next steps
Using the SWI web map tools and dataset directions
SWI map limitations

Disclaimer: While the map helps provide guidance about where wetlands or waters may be located, it is for informational and planning purposes only and serves as neither the delineation that is required for state removal-fill permits, nor does it serve as a determination. The boundaries of the identified resource are only approximate. There may be unmapped wetlands and other waters present that are subject to regulation. The map represents conditions that existed at the map date and may be subject to change. Always work with DSL or a professional to identify if a resource is present. Learn more.

Local Wetlands Inventories

Professional consultants and local governments have created inventories of wetlands and waters in various areas throughout Oregon. These inventories identify approximate locations of wetlands and waters. There may be unmapped wetlands or waters in these areas that are still regulated. More information about LWIs is in the SWI map limitations document.

Disclaimer: Information shown on this map is for planning purposes, represents the conditions that exist at the map date, and is subject to change. The location and extent of wetlands and other waters is approximate. There may be unmapped wetlands and other waters present that are subject to regulation. A current Oregon Department of State Lands-approved wetland delineation is required for state removal-fill permits. You are advised to contact the Department of State Lands and the U.S. Army Corps of Engineers with any regulatory questions

Inventory Resources for consultants developing LWIs:
LWI GIS Data Description
LWI Template Data
Oregon Wetland Mapping Standard