UPPER RUVU TREATMENT PLANT
The intake of the UR plant is located 65 km west of DSM. Raw water is pumped to treatment works 6 km away at Mlandizi.The first development of this scheme of capacity 18,000 m3/d occurred in 1959 and has been expanded in stages to reach a capacity of 82,000 m3/d. The treatment plant comprises the following:
• Intake on the Ruvu River: First intake constructed in 1956, another in 1991. Minimum recorded flow in the Ruvu River at the intake site was 1.72 m3/s in January 1961, maximum flow 1180 m3/s in April 1983. Design and operating capacity of the intake is > 2.21m3/s.
• Raw water pumping station: Single compartment sump receiving raw water from the grit chamber overflow, 4 vertical pumps of discharge 0.37 m3/s
(3 duty + 1 standby), and head 66 m, total pumping capacity 1.1 m3/s.
• Raw water pumping mains: 3 welded steel mains of diameters ranging from DN 350 to DN 760 mm in a distance of 6 km.
• Chemical room: Chemicals dosed into a single raw water main.
• Clarifiers: 32 units of upflow solids contact type, dimensions 7.5×7.5×5.5 m depth each, total capacity 1.1 m3/s.
• Filters: 15 units of rapid gravity sand filters of Paterson Candy type.
• Disinfection: Pre and post chlorination gas.
• Clear water tanks: 2 compartment reinforced concrete circular tank adopted on ground, dimensions 40 m diameter and 4.5 m height, total capacity 5,450 m3.
• Clear water pumping station: 4 horizontal pumps (3 duty + 1 standby), of discharge 0.316 m3/s and head 205 m (operating head 155 to 170 m), total capacity 0.95 m3/s.
System Upgrade (2011-2015)
The plant have recently been expanded to increasing water production in the water works facilities by 50%; thus increasing the treated water output from 82,000 to 196,000 m3/d. The expansion work has been completed and the new plant will be in full production from March 2016
The new additional water pipeline to transfer the additional 114,000 m3/d (total flow 196,000 m3/d), is being constructed and will start operation in March 2016.