There's too much water so Israel opens the floodgates unto Gaza - just like that

Maybe I should have paid more attention to the news of the flooding of Gaza on the 18th of January, due to the fact that Israel opened the floodgates in a dam that has been closed for years. The dam stops the natural flow of a wadi that runs south from Hebron through Gaza into the sea. Under normal circumstances the dam depletes the Gaza aquifer from (part of) its natural inflow.
This is what the human rights organisation Al Mezan had to say about the Israeli actiion::

For the second time in the past ten years, at approximately 6pm on Monday 18 January 2010, Israel opened the floodgates of one of the dams in the Gaza Valley, which flows into Gaza from the east. As a result, dozens of Palestinian houses and properties were damaged. Israel built this floodgate to prevent the rainwater's natural flow into Gaza, depriving the Gaza aquifer from its main natural source of underground water.

According to Al Mezan Centre for Human Rights field workers, the water flooded both sides of the Gaza Valley, causing harm to the Palestinian houses; agricultural land and other properties.

 Dozens of Bedouin families live in that area. According to Al Mezan's field workers, about 50 families live in tents in that area. Water reached about two meters above the valley's level and flooded their houses. Other families who have been living in the watercourse in the valley, which has been dry for many years due to the Israeli dams, had left the area two days before the flood occurred due to the heavy rain.  The mayor of the Gaza Valley village (Juhr Ad-Dik) told Al Mezan that about seventy houses were flooded, dozens of poultry and sheep died, and several personal belongings were damaged as people were surprised by the sudden flow of water.

  A similar situation had occurred when the so-called Nahal Oz dam suddenly collapsed nine years ago, on 26 March 2001. Hundreds of donams of agricultural lands; chicken and cow farms; and rural houses were damaged. Then, the Israeli authorities took precautions on their side of the border before the collapse; however, they did not inform the Palestinian authorities with whom they had regular coordination at the time.

 In the light of the above, Al Mezan asserts that the Israeli authorities bear the responsibility for the moral and physical damages resulted from this sudden water flow into the Gaza Valley.