China is investing $10 billion to build a new port at Bagamoyo (northwest of Dar es Salaam) and improve infrastructure related to the port improvement. This will make it possible to greatly increase trade. This mainly consists of shipping raw materials to China and bringing Chinese manufactured goods in. Among the imports will be most of the components for the ports and Chinese mines and other infrastructure projects in the region. The new port will be able to handle 20 million cargo containers a year. The current port facilities at Dar es Salaam can only handle 800,000 containers a year. New roads and railroads will connect to existing road and railroad networks, and these will also undergo upgrades. This will make Tanzania the main port for raw materials coming out of and goods going into Malawi, Zambia, Congo, Burundi, Rwanda, and Uganda. This makes Tanzania a major East African shipping destination because Bagamoyo will become the largest port in Africa and one of the biggest in the region (which includes the Persian Gulf).
Although China made it clear that these facilities will not be used by the Chinese Navy, Chinese firms will run (as well as build) the facilities, and getting an agreement from Tanzania to allow Chinese warships to come by for supplies and shore leave should not be a problem.
The Chinese government has refused several navy requests for overseas bases but as more Chinese warships operate in the Indian Ocean, and off East Africa, there will be a need for ports where these can reliably obtain fuel, supplies, and some repairs. What better port than one run by a Chinese company. China has a similar deal with Pakistan, where the port of Gwadar (located near the Iranian border) is being upgraded by China. The Chinese plan to also build a naval base that would be used by Pakistani and Chinese warships and aircraft. This would be a Pakistani naval base, which the Chinese Navy having access.