Wetland Areas

Wetlands are areas that are inundated or saturated by surface water or ground water at a frequency and duration sufficient to support, under normal conditions, a prevalence of vegetation adapted for life in saturated soil conditions (hydrophytic vegetation). A wetland is identified under the current federal wetland determination methodology based upon three attributes: hydrology, soils, and vegetation.

Lake County inventory maps can be used as a preliminary guideline to determine possible wetlands in the area. If the maps indicate the potential presence of wetlands on a site or if site conditions warrant, a Jurisdictional Determination and or Wetland Delineation may be required.

Wetland Jurisdictional Determination (JD)

A jurisdiction determination (JD) is the first step in the site evaluation process to ascertain the presence of a wetland on a property. A wetland determination is a general evaluation and does not provide a demarcation of wetland boundaries. The JD also determines which wetlands are designated as Isolated Waters of Lake County (IWLC) and those that are under U.S Army Corps of Engineers (USACE) jurisdiction. The USACE has authorized Building and Engineering Division to perform wetland jurisdictional determinations for all of unincorporated Lake County. If there appears to be potential wetland impacts as a result of the proposed development, or if more precise information is required following a wetland determination, wetland delineation may be required.

Wetland Delineation

A wetland delineation is a comprehensive on-site investigation of hydrology, soils and vegetation of a specific area performed by a certified wetland specialist. The results of the study define the wetland boundaries and quality based upon the Corps of Engineers Wetlands Delineation Manual. All delineation studies for wetlands under USACE jurisdiction must be submitted to the USACE for review and approval. Isolated waters of Lake County (IWLC) wetlands must be reviewed by the Building and Engineering Division.

Wetland Concurrence

A wetland concurrence is a review and approval of the wetland delineation report and boundary verification.

Wetland Specialists

A list of certified wetland specialists (CWS) published by Stormwater Management Commission's (SMC) can be found online.

More Information

For those interested in developing in areas containing possible wetlands:

  • To apply for a Site Development Permit/Jurisdictional Determination and Wetland Delineation, visit the Lake County Planning, Building and Development Department at the:
    Lake County Central Permit Facility
    500 W Winchester Road
    Libertyville, IL
  • Additional permitting requirements may be necessary to assure compliance with federal, state and county regulations.

For detailed information on wetland regulations and requirements, please call 847-377-2600.