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failure. Thus, while major landslides may rupture such cables, minor settlements or small slides are not nearly as likely to affect such cables as they are to break buried gas or water pipes. Above ground communications and cable television cables are subject to wind- induced failures from tree falls and pole failures. However, such failures are about ten times less common than failures of electric power lines. The better performance of communications cables arises in part because the electrical cables are always highest on the poles, thus a falling branch is usually first resisted by the power cables. Also, because the voltage levels in communications cables are much lower than those in power cables, the communication cables are not subject to "burn down" or shorting if wind-swayed cables touch each other or get too close. Some telecommunications facilities are subject to failure as a result of loss of electric power. However, key facilities almost always have backup battery power and/or generators. Therefore, telecommunications facilities are generally much less vulnerable to outages from loss of electric power than are water or wastewater systems. Possible mitigation projects for telecommunications systems include flood proofing of important nodes, adding back-up power, relocating facilities out of active slide areas and seismic retrofits. 13.7 Electric Power Systems The electric power system is central to the functioning of a modern society. The consequences of loss of electric power are very large: residential, commercial and public customers are all heavily dependent on electric power for normal functioning. Furthermore, as discussed above, other utility systems, especially water systems, are heavily dependent on electric power for normal operations. Loss of electric power, therefore, may have large impacts on affected communities, especially if outages are prolonged. The Regional All Hazard Mitigation Plan for Benton, Lane, Lincoln and Linn Counties included reviews of the operating characteristics of electric power systems and the major failure modes (Phase One, Technical Appendix). We briefly summarize this information here. Electric systems have three main parts: generation, transmission, and distribution. Generation is the production of electric power. Generating plans can be hydroelectric, fossil fuel (oil, gas, or coal), nuclear, or various renewable fuels (wind, solar, biomass, etc.). Most of the electric power consumed within Lane County is thus produced elsewhere and transmitted via high-voltage transmission lines. The Bonneville Power Administration (BPA) is the primary source of power for Lane County. BPA's power comes from hydroelectric facilities (57%) operated by the Corps of Engineers or the Bureau of Reclamation, from a nuclear plant (3%), from interchanges and wheeling (37%) of power transmitted by BPA but not owned by BPA and from other sources (3%). Through the Pacific Interties (high voltage AC or DC transmission lines) power Public Review Draft: August 6, 2004 13-7