What right does Egypt have to demand that Ethiopia not build a dam on its own land

What right does Egypt have to demand that Ethiopia not build a dam on its own land
Since the first foundation stone was laid on the Grand Renaissance Dam (GRD) Egypt has shown its eternal belligerence towards Ethiopia, demanding Ethiopia honor the 1929 and 1959 Colonial treaties. At times Egypt walks out from the negotiations; at times it pretends to go along with the agreements but refuses to sign the Nile Basin Treaty; at times Egypt demands more studies to be done, refusing to accept various studies done so far; at times it threatens it would wage war. And it continues to harp on its “Historic Right” over the waters of the River Nile.

Abdelatty, spokesman of Egypt’s Foreign Ministry, said: “Ethiopia should also respect colonial-era agreements and the 1959 accord between Sudan and Egypt that allocates all of the river’s flow excluding evaporation to those two nations… By 2020, Egypt will require all of its assigned 55 billion cubic meters a year for vital use such as drinking, washing and sanitation”



The Grand Ethiopian Renaissance Dam construction progress.