As lack of rainfall contributes to shallow lake levels, transport on the world's second largest lake is growing trickier
NANSIO, Tanzania (AlertNet) – The sound of the MV Nyehunge’s horn signals the ferry’s arrival at the port of Nansio on Lake Victoria. Veronica Mayola disembarks and tries to get out of the pouring rain.
But Mayola, who is returning to her home town here on the island of Ukerewe, cannot take shelter in the passenger lounge built by the Tanzania Ports Authority. It was constructed to serve the original Nansio pier – but the water is now too shallow for the Nyehunge to berth there. Instead, the ferry must dock at a new landing site, far from the lounge.
The water level at the original Nansio pier has gradually been dropping since seasonal rainfalls began to lessen in the early 1990s, and it is now below the required minimum anchorage depth, explains Port officer Bulenga Ndaro.
“To date the quays have conceded two metres of waters,” Ndaro says in frustration.
Climate experts believe that changing rain patterns at the world’s second largest lake, consistent with expected climate impacts, are contributing to the problem, and that further changes are possible.
“The timing of rains will become less predictable and their intensity is likely to become more volatile,” noted a recent paper by the United Nations Environmental Programme (UNEP).
Johnston Mutalemwa, an engineer and the port master at Mwanza, 29 nautical miles from Nansio on the south side of the lake, says that problems with the draft of vessels (the depth at which they sit in the water) when at port have become commonplace on Lake Victoria.
Mwanza serves as a hub port but faces the same predicament as Nansio. Port Officer Abdulrahman Kaponta says that the port has lost about five metres of its anchorage depth at the quays.
To cope with the change, one ship which berths at Mwanza on a regular basis, the MV Victoria, has had its passenger doors repositioned because the old ones had become inaccessible.
The Nyehunge plies the Mwanza-Nansio route daily with passengers and cargo. Adam Alex, one of its skippers, points to an islet of earth and rock which has emerged from below the lake’s surface in recent years and is now used by fishermen as a transit point.
The islet now even has its own name, Makobe.
“We used to manoeuvre the ferry through the (islet) but now we are forced to manoeuvre on starboard to avoid running aground,” Alex said.
The low water levels have forced one of the lake’s principal transport businesses, Marine Services Company (MSC), to replace one of its ferries plying the Nansio route, the MV Serengeti, with a smaller one, the MV Clarias. The Clarias can carry 250 passengers and 10 tons of cargo, compared to the almost 600 passengers and 350 tons of cargo that the larger vessel was able to carry.
Since reducing the service in 2003, MSC estimates that it has been losing 226 million Tanzanian shillings ($143,000) annually on the route.
Nansio is gradually becoming a satellite settlement for the rapidly growing city of Mwanza. The island of Ukerewe, with a population in excess of 260,000, supplies fish to Mwanza’s markets.
But the port authority, which owns and operates Nansio port, has halved its staff there to just two now because of the drop in business. MSC has also stopped serving small ports such as Kome, Mwanoni, and Nyamurenge.
Alex Mchauru, MSC’s general manager, acknowledged that these ports are important to the rural economy, but he said they lack sufficient water for ships to berth with ease.
Mchauru said that the company is looking at ways to retrofit its fleet to tackle the draft decrease at the lake’s ports.
The Nyehunge, whose installed draft is 1.6 metres, has become the main means of transport for residents of Ukerewe since MSC withdrew the Serengeti from the route.
The islanders use the ferry to bring home foodstuffs, electronics, motor vehicles, spare parts and timber.
Because the vessel cannot berth in shallow waters for fear of running aground, MSC has been allocated a previously unused area of Nansio to build its own landing site. But the Nyehunge’s skipper, Adam Alex, says that it is still a challenge to dock because of the changing depth of the water.
“It’s a cat and mouse chase… When the water’s depth decreases we have to move the landing site towards the lake to regain the allowable anchorage depth,” Alex said. The company uses earth and stones to extend the landing site further into the lake.
Mwanza’s port officer Kaponta agrees with the skipper and predicts that in the future the lake’s ports will have to chase the receding water farther to find acceptable anchorages.
Mohamed Issa is a freelance writer based in Dar es Salaam. This story is part of a series supported by the Climate and Development Knowledge Network.
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