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Section 404 of the Clean Water Act

Advance Identification (ADID) of Disposal Areas under CWA Section 404

This fact sheet describes the advance identification of disposal areas (ADID), a planning process  used to identify wetlands and other waters that are generally suitable or unsuitable for the discharge of dredged and fill material. It highlights how the ADID process works and the status of ongoing projects.

How the ADID Process Works

The ADID process involves collecting and distributing information on the values and functions of wetland areas. EPA conducts the process in cooperation with the U.S. Army Corps of Engineers and in consultation with States or Tribes. Local communities can use this information to help them better under stand the values and functions of wetlands in their areas. It also serves as a preliminary indication of factors likely to be considered during review of a Section 404 permit application.

The ADID process is intended to add predictability to the wetlands permitting process as well as better account for the impacts of losses from multiple projects within a geographic area.

Although an ADID study generally classifies wetland areas as suitable or unsuit able for the discharge of dredged or fill material, the classification does not constitute either a permit approval or denial and should be used only as a guide by community planners, landowners, and project proponents in planning future activities. The classification is strictly advisory.

Status of ADID Projects

As of February 1993, 38 ADID projects had been completed and 33 were ongoing. The projects ranged in size from less than 100 acres to more than 4,000 square miles and are located from Alaska to Florida.  ADID projects can be resource-intensive activities, although some have been completed in as little as six months.

Regional EPA experience indicates that the smaller or more local the ADID project boundaries, the more complete and effective the analysis and results. For example, ADID projects have been initiated by local entities to facilitate planning efforts such as the one described in the Case Study for West Eugene, Oregon (see sidebar). These local efforts have proven to be one of the more successful ways of generating support for wetlands protection. Local cooperation and support are vital to the success of ADID projects.

Case Study - West Eugene, Oregon

In the West Eugene, Oregon, Wetlands Special Area Study, local ADID efforts led to a Section 404 general permit. Because the ADID was incorporated into the City of Eugene's general comprehensive plan, and because Oregon land-use policies have the effect of local land-use law, the ADID effort streamlined the regulatory process.

The number of ADID projects has increased over time, and EPA expects more States, Tribes, localities, and private organizations to become involved in providing funds and otherwise supporting ADID or other comprehensive planning efforts.  Because ADID efforts are usually based on watershed planning, they are extremely compatible with geographic and ecosystem initiatives such as EPA's Watershed Protection Approach.