About FURUICHI TETSUYA
About 東京都 下水道局
About Tokyo Metropolis
About sewage treatment plant
About combined sewerage
About improvement
About palace
About pond
About rain water
About liberation(aquatic)
About sewage
About separate sewerage
About environmental assimilating capacity
About pollution loading amount
About 下水放流
About imperial palace
About improvement of combined sewer
About 水質悪化
About improving water quality
About 内濠
About Sewerage engineering and wastewater treatment in general
About 視点
About 合流改善
About 皇居
About 濠
About 水質改善
About 将来