adjustment
and it
arakawa
arakawa first control in drainage gate
blue sky
building
buildings
buoy
concrete
control area
control pond
creature
drainage
drinking water
flood
gate
heavy rain
heavy rains
lake
living organism
management
microorganisms
plankton
pond
rain
rain water
rainfall
rainy season
regulation
reservoir
revetment
rising
river
sai lake
saitama
saitama prefecture
shore
surveillance
the rainy season
toda
typhoon
volume of water
wager
water
water bearers
water gate
water level
weather