Wetland & Buffers Program
The primary mechanism to implement the wetland and buffers program is the
DuPage County Stormwater and Flood Plain Ordinance. Since many wetland functions are difficult and expensive to replace, the Ordinance requires that an applicant avoid or minimize impacts to wetland if possible. Wetland impacts are be replaced, or
mitigated, in the same watershed. Impacted buffer functions are replaced in kind. Wetland replacement ratios and buffer widths are based on the quality of a wetland which is determined by analyses of habitat and vegetation quality, and the presence of Endangered or Threatened Species.
DuPage County developed wetland maps in the late 1990s. Since that time, development in the County has significantly changed the landscape. In 2015, the County completed a modernization of these maps. This will allow the County to provide more accurate information to
residents, developers and businesses. In addition, these maps may be used as a planning tool. They can be viewed as a layer on the County's GIS maps.
The Wetland Banking Program was adopted by the Stormwater Management Planning Committee and County Board in 1993 to give the development community the option of offsite wetland replacement while keeping the significant benefits of wetlands in the same watershed as the impact. Wetland bank fees are
based on a detailed cost estimate unique to the project. When a wetland mitigation bank is not available, developers may choose to pay a fee of $175,000 per acre. The fee is used by the county to construct the replacement wetland in a future bank project when one becomes available.
The County has several wetland banks and wetland mitigation projects in various stages of development. The Cricket Creek and Downers Grove projects have both been completed. Springbrook Prairie is in its maintenance phase, and two other projects, located in West Branch and Danada Forest
Preserves, are currently in design.