Moreover, a feasibility study projecting the dam’s likely generation capacity was conducted quarter of a century ago, before upstream irrigation and climate change reduced water levels in the Rufiji.
“The river has lost 25 percent of its capacity in the past 25 years,” says Zitto Kabwe, an economist and leading opposition politician who has frequently been arrested for criticising the government.
“It is not possible to produce the electricity talked about.”
The funding, too, is murky. Mr Magufuli insists Tanzania can pay for the dam itself.
Yet the government’s claim that funds will not be sought from China — potentially saddling the state with crippling debt — by registration books at the entrance to the Selous. These show that large numbers of employees from two state-owned Chinese companies, SinoHydro and Power China, have been visiting the construction site every day.
In the meantime, the Selous is already being radically altered.
Loggers, most of them reportedly prisoners, have begun clearing an area of threatened Miombo woodland the size of Surrey to make way for what will be East Africa’s largest artificial reservoir.
Elsewhere, quarries are being gouged out and bridges laid to accommodate heavy-duty vehicles.
Yet that is only the start. If completed, the nature of the Rufiji would forever change as sandbanks where hippos and crocodiles bask are submerged and its stunning oxbow lakes disappear.
Further downstream there would be devastation, too, as the vast Rufiji Delta, one of the continent’s most important wetland sites, shrinks, threatening disaster for East Africa’s largest endangered mangrove forest.
Ionides’ vision of an untouched wilderness, and the miracle of regeneration he wrought, is rapidly unravelling.
“The Father of the Selous” did not create the reserve; a small protected area was carved out Tanganyika’s German governor in 1896. But, as game warden after Britain took over following the First World War, he increased its boundaries 20-fold. It now encompasses 22,000 square miles.