Yes but lake Nassar is clearly not enough. Egypt has legitimate concerns, but I do not think these 3 can take the ego and emotion out of it. They really need external facilitators. The new dam can benefit all 3 I don't see why they cannot base it on maintaining lake Nassar at a certin range of levels based on certain annual outflows. if there is a drought the filling slows, heavy rains, it speeds up
Because Ethiopians don't need anyone to tell them how or when to fill the lake behind the dam .
There is no such thing as an earthquake proof structure, but you can put structures down river to divert and break up the water front to minimise the damage if it should fail.
The technical studies should be done by a common engineering committee between the three countries to evaluate the geologic, hydraulic, and seismic design criteria and design criteria . Sudanese life also matters .
Perhaps as a richer more powerful country you could invest and help your neighbour instead of threatening them and taking them to "court"... I would think better relations would be good for both countries...
Egypt didn't threat them by a military action ,actually the negotiations is going on sine 9 years !
Actually Egypt has helped Ethiopia alot before , by building hospitals and sending doctors , building power plants ,cultivation and construction projects .
But Ethiopia always find a reason to withdraw ,they think the water is theirs and they are giving it as a gift to Sudan and Egypt .
But 150 million people are depending on this water and the Egypt-Sudan requests are simple , we don't want a decrease in the flowing water .Sudan also complained them in the security council .