We have been ordered by Dam Integrated Control Office to stop using dams 
for 3 pumped storage power stations under the regulation of dam operation, 
as the water surface of the dams had elevated by heavy rain caused by the 
Typhoon No. 12. Therefore, during the period of usage restrictions, 7 GW 
of supply capacity of pumped storage power stations will reduce to 5.3 GW 
tentatively.

In particular, 2,325 MW of power by Tanbara Power Station of TEPCO 
(Location: Tone-gun, Gumma Pref., Plant Capacity: 1,200 MW), Shin-Toyone 
Power Station of J-Power (Location: Kitashitara-gun, Aichi Pref., Plant 
capacity: 1,125 MW, Capacity received by TEPCO: 450 MW) and Numahara Power 
Station of J-Power (Location: Nasushiobara City, Tochigi Pref., Plant 
capacity: 675 MW, Capacity received by TEPCO: 675 MW), will be stopped 
tentatively. We estimated supply capacity of pumped storage power stations 
again, and reduced the supply capacity to 5.3 GW. 

Although we have the conditions above, we assume we can maintain enough 
reserve capacity and there will be no difficulty in securing stable 
electric power supply in our service area.

In addition, as our power stations and dam facilities have no damages such 
as destructions at present, the power stations will be ready for restart, 
when conditions of weather and rivers get improved after the Typhoon passed. 

<Reference> 
  Supply and demand outlook within TEPCO's service area (as of 11:00 am)