The article mention : "Egypt fears its supplies will be reduced during the time it takes to fill the 74-billion-cubic-metre capacity reservoir." From information that I can find, the filling can take up to 7 years !
Your own heat map shows that this isn’t the case - they also live on the coast.
Earlier it was ‘all’.
That's the delta.
More detailed excerpt for other HN readers stumbling on this comment:
> Ethiopia, one of Africa's fastest growing economies in recent years, insists the dam will not affect the onward flow of water.
> But Egypt fears its supplies will be reduced during the time it takes to fill the 74-billion-cubic-metre capacity reservoir.
> Egypt considers the dam as a threat to its existence and Sudan has warned millions of lives will be at "great risk" if Ethiopia unilaterally fills the dam.
> A decade of negotiations have failed to result in a deal.
Egypt has been taking advantage of this, allowing the "overflow" from their dam/lake nassar to be syphoned off into the desert, to the extent of trying to develop an entirely new drainage valley into farmland.
It is a mega project.
Any upriver country that is able to divert the "overflow" water before it gets too Egypt can keep it.
So it's basically an argument over who gets to keep the surplus in the water balance of the river.
>[1]Use of Nile resources is governed by the Nile Basin Initiative; but the Toshka project does not breach the agreement as water is diverted from Lake Nasser only after heavy water flows upstream have raised lake levels above 178 metres (584 ft) (see above).
[1]https://en.wikipedia.org/wiki/Nile_Basin_Initiative
From the article, the Nile river is estimated to carry 84 billion cubic meters per year, so the reservoir holds roughly one Nile-year of water. Filling over 7 years means that the downstream flow would be reduced by ~1/7 during that time period.