When most Americans face an electrical power outage at our home or business, we're talking about minutes or, at most hours, without electricity.

But when the small villages and rural homes located on many of South Dakota's reservations lose power, they often are dealing in days - in some cases a week or more - without electricity. In those remote places, that can mean the difference between life and death for the elderly, the weak and the medically fragile.

The icy winter storms that crippled much of South Dakota in recent days took an especially big toll on the people of the north central part of the state. On the Cheyenne River Indian Reservation and other places, about 5,700 rural electric customers were still without electricity on Tuesday, five days after ice-covered power lines began snapping late last week. Yesterday, more than 6,000 power poles were on the ground across northern South Dakota as crews battled sub-zero wind chills and poor visibility to repair them.

Adding insult to injury, the rural water system that serves about 14,000 customers on and near the Cheyenne reservation was out of operation on Tuesday, forcing the state Office of Emergency Management to haul in potable water.

Those power outages and water shortages have hit hard in a place where people already struggle to provide the basic necessities of life, such as heat and electricity. A late 2008 blizzard on the Pine Ridge Reservation left some in the Wanblee area without electricity for more than a week. This storm promises a similar result on Cheyenne River. Many reservation homes rely on electric heat sources, especially once the propane tank runs dry, so electricity can mean life and death in severe cold.

Electrical outages hit even harder at one particularly vulnerable group of people: dialysis patients who need regular medical treatment that tethers them to a machine, powered by electricity, that remove toxins their kidneys are no longer able to eliminate. We applaud the tribe's emergency evacuation effort that got 35 patients the care they needed at other dialysis centers in Rapid City and Pine Ridge. Following a Christmas blizzard last year, the Oglala Sioux Tribe faced a similar challenge in getting dialysis patients on the Pine Ridge the medical care they require in the wake of blizzard-closed roads.

As the dialysis needs in Native American communities continue to grow, tribal officials must focus on preparing updated, well-coordinated evacuation plans to deal with the inevitable winter weather that we know will complicate the delivery of those lifesaving medical services.