BBC-Senegalese MPs have voted to abolish the senate as part of moves to help the victims of recent deadly floods.
President Macky Sall has said the money reserved for the upper house – about $15m (£9.5m) – will also go towards preventing further flooding.
But critics say the aim is to weaken the opposition as most of the senators were supporters of the ex-president.
The 100 senators had fought to be retained, but lost the vote in the joint session of parliament.
The Congress also abolished the post of vice-president – although no-one has held the position since it was created in 2009 by then-President Abdoulaye Wade.
Low-lying suburbs of Senegal’s capital, Dakar, flood during most rainy seasons, but this year has seen exceptionally high rainfall across West Africa.
Thirteen people died in Senegal and it is estimated that thousands of people have been left homeless.
Before President Sall announced his intention last month to abolish the Senate, residents took to the streets of the capital to denounce the government for failing to act faster and were dispersed with tear gas.