JOHANNESBURG (AP) — A conservation group says Tanzania's agreement with Egyptian companies to build a huge hydroelectric dam in the Selous Game Reserve risks damage to an important wetland and could hurt the livelihoods of over 200,000 people who live downstream.

The WWF group criticized the project after Tanzania on Wednesday signed a $3 billion deal to construct the Stiegler's Gorge dam in the Selous wildlife area, a UNESCO world heritage site.

WWF says a thorough environmental assessment was not done as required by Tanzanian law, and urges Tanzania to first explore other renewable power ideas.

Tanzanian President John Magufuli, however, says the dam will cover only a small part of the Selous. He also says a new electricity supply will help to reduce deforestation by people who cut down trees for charcoal.