Wetland Mitigation Restoring Montana's Wetlands

These maps demonstrate the use of GIS in determining potential sites for wetland mitigation in Montana. The benefits of wetlands have been misunderstood and/or underrated, and wetlands were not valued as natural water purifiers and flood control systems. These areas also play an important role in providing feeding and breeding grounds for wildlife species, especially migratory waterfowl. Thousands of acres have been lost to agricultural, industrial, and urban uses. To make up for the loss of this natural resource, Montana is interested in reclaiming these wetlands.

Wetland mitigation is a function of economic development and natural resource conservation. Recently, land developers have been required to compensate for the loss of wetlands in past and present land developments. Because of the high cost of restoration or creation of wetlands, the Montana Department of Natural Resources and Conservation (DNRC) explored the use of GIS technology as a tool to locate potential sites for mitigation on state-owned lands. DNRC solicited the assistance of the Montana Department of Administration's GIS Coordination staff to develop a GIS pilot application.

For a data source, the application used the Natural Resource and Conservation Service's Soil Survey Geographic (SSURGO) data. SSURGO data is used to determine the proximity of hydric soils (inferring wetlands), the potential for wetland plant growth, the height of the water table, and the existence of gravel deposits. By adding cadastral and transportation data, potential mitigation sites on state lands close to existing highways can be identified.

The cost–benefit of using GIS technology in the determination of suitable lands for wetlands mitigation is high. Field checks on pilot areas revealed a high restoration potential for many of the projected sites. Potential cost savings in man-hours is significant compared to the cost of field investigations. The use of GIS technology in these types of land use analyses is promising and will ultimately change the way Montana state government conducts business in the future.