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252 J. R. SHUMAN sediment wave has elongated and diminished in amplitude, and will ultimately flush through the system in 50 to 80 years (Simons and Simons, 1991). The Woolen Mills Dam on the Milwaukee River in West Bend, Wisconsin was removed in 1988. This dam was 4.3 in high and impounded 27 ha. In 1979, the Wisconsin Department of Natural Resources (WDNR) ordered the City of West Bend to either repair or remove the dam to resolve issues of public safety (Nelson and Pajak, 1990). In 1986, the City asked the WDNR to develop a feasibility and implementation plan for dam removal and a 10-year plan for stream restoration in the impounded area following removal. After review of these plans, the City chose the dam removal alternative based on economic, social and environmen- tal considerations. Following dam removal, most of the sediment within the 2.4 km of formerly impounded river channel was scoured out within six months. The river bottom substrate now is composed of mostly gravel and rubble. Fish habitat restoration was an important component of the Woolen Mills dam removal feasibility and implementation plan. Following dam removal, the entire riparian zone was disced, dragged and planted with barnyard grass (Echinochloa spp.) and smartweed (Polygonum spp.) to protect exposed soils from erosion (Nelson and Pajak, 1990). Based on results from the smallmouth bass habitat suitability index models applied to the Milwaukee River, improvement of pool depth and cover were two targeted fish habitat improvements following dam removal. River channel reconstruction and excavation and river bank improvement were completed to increase pool depths. A floodplain analysis was completed to deter- mine the potential for flooding problems due to the reconstructed river channel. Silver maple and swamp white oak transplants were planted along the river banks to provide canopy cover. Other fish habitat improvements have been made since dam removal which have resulted in improvements in the smallmouth bass fishery. Anglers are catching adult smallmouth bass, and young of the year smallmouth bass have been observed in the restored river. Another dam removal which provides an insight into the consequences and environmental assessment needs for dam removal is the Sailing Dam removal on the AuSable River near Grayling, Michigan. This 5.2 in high dam impounded approximately 22 ha along 3.2 km of the AuSable River, and functioned for hydroelectric generation until 1952 (Pawloski and Cook, 1993). The Sailing Dam was inspected in 1980 and found to be structurally unsafe. In 1988, the private owners of the dam were ordered to repair or remove the dam. As the owners could not afford to repair the dam, they entered into a consent agreement with the Michigan Department of Natural Resources which allowed the Department to remove the dam and restore the river to its free flowing state. Before removing the Sailing Dam, written procedures were developed to accomplish the drawdown of the impoundment in a safe manner while minimizing impacts. The nature and extent of accumulated sediments was investigated. No contaminated sediments were found, and the accumulated sediments in the impound- ment were generally less than 1 in thick and consisted of flocculent organics in the downstream two-thirds of the impoundment and sand in the upper third (Pawloski and Cook, 1993). The exact quantity and probable movement of the sediments were not determined. Drawdown procedures also required periodic monitoring of water quality, with stipulations that the drawdown should cease whenever water quality was unacceptably deteriorated. A 61 in long, 4.6 in wide and 1.8 in deep sediment trap was constructed on the upstream side of the temporary drawdown sheet pile structure to trap sand sediments during the drawdown. Exposed floodplain soils were stabilized by reseeding with annual rye grass to minimize erosion. All disturbed areas were covered with topsoil, seeded and mulched. The Sailing Dam removal, completed in 1992, caused significant local controversy. The controversy centred on the possible reduction in property values, whether property ownership would extend down to the river's edge after the drawdown, altered or reduced recreational opportunities, sediment transport to downstream areas and flooding potential without the dam. Most complaints after the drawdown related to the flocculent organic sediments transported downstream during the drawdown. The removal of the Columbia Falls Dam on the Pleasant River in Maine was unique in its ultimate purpose. The Columbia Falls Dam was part of the Pleasant River Hydro Project, which was fraught with problems, including cost overruns, equipment failure and dry years (Ayer and Lagassa, 1989). The dam was removed in 1989 by Bangor Pacific Hydro Associates as mitigation for improvements to their West