As said, why not open floodgates, also why do it in a way that may have caused Russian casualties and as pointed out before the tactical advantage was much greater for Ukraine than for Russia.
And let’s not forget Ukraine is invading nothing, forget about the famed “Spring Offensive” that never sprung?
Occam’s razor clearly points to Ukraine.
Complete nonsense, flooding causes more problems for the attacker. That's why Soviets blew dams in WW2.
Second world war: Dnieper dam blown up by Russians – archive, 1941
Stalin’s secret police blew up the dam in an attempt to slow the advance of Nazi German troops as they swept through Soviet-era Ukraine
Blown up dam at Zaporizhzhia, 1941