5.5 Energy Production and Mining
Waldner and Clark 2009) . Further research is needed to investigate the efects chemicals used in fracking will have on wildlife.
5.5.4 Hydropower—Anticipated Impacts
Hydropower is created by harnessing the energy of falling water. In North Carolina, large rivers and high gradient streams have been dammed in the past to create impoundments for hydroelectric power production. Some reservoirs in our state were created solely for the purpose of creating hydropower. For other reservoirs, hydropower is one of several purposes of the impoundment, along with food control or water supply creation. More recently, existing dams have been retroftted to allow operators to generate hydropower. In recent years, some inoperable hydroelectric plants have been removed to restore streams and rivers to a free-fowing state. Hydroelectric plants have similar impacts as other impoundments: streams and rivers impounded by dams are changed from lotic systems to lentic systems. Downstream water quality can also sufer from low dissolved oxygen (DO) levels and altered temperatures (lower water temperatures if water is released from near the bottom of the reservoir). In addition, hydropower generation can signifcantly change fow regimes downstream of hydropower dams. Large hydropower facilities are typically peaking operations: they generate electricity during peak demand periods. As a result, large volumes of water are released to generate electricity during peak energy demand periods and water releases diminish during low energy demand periods so that the available water supply can be replenished for future use. Tis results in a fow regime that can be vastly diferent from the natural fow regime in terms of magnitude, frequency, duration, timing, and rate of change (Pof et al. 1997) . Tese fow regime alterations can cause changes to the aquatic community, including local extir- pation of species. Dams also fragment habitats and disrupt the movements and migrations of fsh and other aquatic organisms. Diadromous fsh are those that spend part of their life in the ocean and part of their life in freshwater. Tey include Striped Bass, American Shad, American Eel, and Shortnose Sturgeon. Tese species are particularly vulnerable to blockages imposed by dams. Upstream and downstream passage facilities and strategies are often required to reconnect populations of these species to their necessary habitats. Te combined efects of barriers and altered fows can afect other important riverine processes, such as bedload and sediment transport, nutrient cycling, and woody debris transport.
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2015 NC Wildlife Action Plan
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