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　Countermeasures for tsunami in islands　We are promoting comprehensive countermeasures from both the hardware and software sides, such as creating TMG's own damage assessments due to a massive Nankai Trough earthquake and a tsunami flooding hazard map for a tsunami that could cause enormous damage like that from the Great East Japan Earthquake.Sesmc renforcement of ■oodgates andother measures iiinon-utilitygeneratorsubstationImai Floodgate in normal open positionImai Floodgate closed in preparationfor high tidesEarthquake resistance countermeasures for leveesTatekawa FloodgateShin-onagigawa FloodgateNihonbashi FloodgateKamejimagawa FloodgateOshimagawa FloodgateSumiyoshi FloodgateTsukishimagawa FloodgateSurveillance and control from the Floodgate Control CenterSurveillance from the Floodgate Control CenterCorrespond only to the IP telephoneReinforcement of concrete leveeAdditional reinforcing bars地盤改良地盤改良Ground improvementGenmorigawa FloodgateKitajikkengawa Sluice GateKiyosumi Drainage Pump Station(backup)Kinoshita Drainage Pump StationOgibashi Lock GateUchikawa FloodgateUchikawa Drainage Pump StationSelf-supporting line for surveillance and control (optical ■ber cable)Dedicated line for commercial useControlling of gravity descending by the radioIllustration of earthquake and ■ood resistance countermeasuresFloodgate Control CenterKinoshitagawa Center Set up the facilities at ahigher positionConcrete thickeningSeismic strengthening of the administration buildingFlood gatesReinforce ■xing of theopening/closing facilitiesHanabatake FloodgateKamihirai FloodgateOnagigawa Drainage Pump StatinonImai FloodgateArakawahigashi FloodgateArakawahigashi Sluice GateArakawa Drainage Pump StationSeismic strengthening of the pillarsWatertight openingsPump installationSeismic strengthening of the lower beamsDrainage pump stationsA conceptual diagram of the floodgate management system　In addition, in light of the Great East Japan Earthquake, earthquake-resistance and flood-resistance measures are being taken for rivers in the eastern low-lying areas to ensure that seawalls and floodgates will continue to function and prevent flooding causes by tsunamis, etc. in the event of an earthquake with the maximum strength considered possible in the future.　River Facilities　Floodgates have been installed at the mouths of rivers in the eastern low-lying areas. These floodgates can be closed when high tides or tsunami occur, joining the gates to the surrounding seawalls to protect the area. Drainage pumps have been installed in preparation for rising water levels on the inside of the floodgates due to rainfall or other factors, and these pumps operate automatically to discharge the water to the outside of the floodgates when the water level rises.　In order to improve the efficiency in operating each facility of floodgates, a floodgate control system was built utilizing various ICT, such as optical communications, wireless telecommunications, and remote surveillance and control are being conducted in the Floodgate Control Center for 24 hours a day and 365 days a year. The system's reliability is enhanced by the backup in Kinoshitagawa Center that has functions that are equivalent to the Control Center's functions and double looping of the communication cables. Closing the floodgates by the wireless telecommunications is also possible.39