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Project information
• Comany entering: UWP Consulting
• Project start date: 14 October 2013
• Project end date: 10 June 2015
• Client: uMkhanyakude District Municipality
• Main contractor: Icon Construction/Veolia
Joint Venture
• Consulting engineer: UWP Consulting
• Project value: R125-million
UWP Consulting was appointed in
April 2011 to commence planning
of the Shemula Bulk Water Supply
Scheme Upgrade, a R845-million bulk
water supply scheme to serve 230 000
people in the northern half of the Jozini and
Umhlabuyalingana Municipalities.
During the preliminary design, the client
decided that the water works itself should
be let as an EPC (turnkey) tender. Certain
elements of the design had already reached
an advanced stage and it was decided to
split the contract into two sub-phases.
Phase IA, a conventional EPCM contract,
included the raw water pumpstation and
rising main, the clear water storage reser-
voir and the clear water pumpstation and
rising main. Phase IB, an EPC contract,
included the full water treatment works
design and construction.
The design of Phase IA was carried out
by UWP while the design of Phase IB was
carried out by the contractor. UWP prepared
a detailed specification for the turnkey
tender to ensure that a state-of-the-art
facility was provided under the EPC contract.
The raw water pumpstation has been
designed as a dry well and consists of a
9 m deep x 7 m diameter concrete structure
embedded in the left bank of the Pongola
River. Generally the flow in the river is kept
constant at 5 cumec and is controlled at the
Pongolapoort Dam some 60 km upstream.
However every September DWS releases
a controlled flood peaking at 600 cumec.
During the flood the water level rises to
within 2 m of the roof of the pumpstation.
To allow for a variable flow rate into the
head of the waterworks in the absence of a
raw water reservoir, variable speed drives
controlled by the works operator were
installed on the raw water pumpsets. Allow-
ance has been made to install larger pumps
when the works is increased from 20 Mℓ/day
to 40 Mℓ/day.
The waterworks layout allows for the
smallest feasible footprint. Emphasis was on
simplicity of operation, operational control
Shemula Water Project – Upgrade:
Phase I – Shemula Water Treatment Works
and maintenance, high performance effi-
ciency and stability together with reliability,
flexibility and economy of operation, as well
as a pleasant working environment.
One of the main design features was
using natural slope of the land to eliminate
the need for any pumping requirements
withintheplantandhencesaveonelectricity.
The filters discharge potable water from
the clearwell directly into the 2,5 Mℓ clear
water reservoir from where a 700 mm dia-
meter gravity main conveys water to the
clear water pumpstation.
The clear water pumpstation, pipework
and rising main have been sized to cater for
the ultimate demand. Allowance has been
made to add a further two pumps alongside
the current four when the plant is upgraded
to 40 Mℓ/day.
The pumps operate at a working pres-
sure of 20 bar and deliver water via a 2 500 m
long x 700 mm diameter GRP rising main to
the existing 4,5 Mℓ command reservoir from
where an existing bulk distribution system
distributes water.
The existing bulk distribution system
is severely undersized and in very poor
condition and Phases 2 to 6 of the scheme
will include bulk pipelines from 700 mm Ø
to 200 mm Ø, terminal reservoirs and
booster pump stations to supply water to
the entire region.