Area of supply
The Algoa Water Supply System (Algoa WSS) extends from the Kouga River system in
the west to the Sundays River system in the east. The Algoa WSS provides water
to the Gamtoos Irrigation Board, 1.1 million people in the Nelson Mandela Bay
Municipality (NMBM) for domestic use and for use by more than 373 industries,
the Coega Industrial Development Zone and several smaller towns within the Kouga
Municipality area.
The water requirements of the NMBM have increased steadily over the past few
years, due to in-migration, increased service levels and industrial activity.
Planning for the Algoa Water Supply System
The purpose of the Reconciliation Strategy is to determine the current water
balance situation and to develop various possible future water balance scenarios
up to 2040. The Strategy was initially completed in early 2010 and was
subsequently updated in April 2011 due to emergency interventions planned as a
result of the drought, as well as revised Coega IDZ water requirements.
Strategy Steering Committee
In 2010 the Department of Water and Sanitation (DWS) and the Nelson Mandela Bay
Municipality (NMBM), developed a Strategy to ensure the on-going reconciliation
of supply and requirement from the Algoa Water Supply System (Algoa WSS). One of
the recommendations of the Strategy Study was that a Strategy Steering Committee
be formed with a clearly defined mandate and scope of work. A Strategy Steering
Committee with membership from the main users and institutions in the area was
constituted in September 2011.
The objectives of the Strategy Steering Committee are to ensure and monitor
implementation of the recommendations of the Algoa Reconciliation Strategy, to
update the Strategy to ensure that it remains relevant, and to ensure that the
Strategy, its recommendations and progress with the implementation are
appropriately communicated to all stakeholders.
Water requirements and availability
The total usage of water from the AWSS in 2011/12 was 149.7 million m3/a. This
comprises urban use by NMBM and various small towns, Coega Industrial
Development Zone potable use, agricultural water use, losses from the
Kouga/Loerie canal, and ecological water requirements. The sectoral water use in
the Algoa WSS for 2011/12 was as illustrated in the pie-diagram below.
The combined yield of the Algoa WSS sources at an assurance of supply of 98%
(1:50 year assurance of supply) is 164.4 million m3/a. The above graph shows the
High and Low Water Requirement scenarios when compared with the Algoa WSS water
yield. It shows that there is still some surplus water in the system and that
any significant increase in use would put the system at risk. Following on the
recent drought, water use has not yet returned to levels before the drought, but
there is a tendency for usage patterns to be relaxed and return to former levels
of use once a drought has broken. The higher the growth in water requirements,
the higher the risk would be, especially if large users in the Coega IDZ were to
be established within the next five years. Measures to augment the yield of the
system should be continued, on account of the long lead times necessary for
implementation.
Supply interventions to meet future needs
The interventions which have been identified as probably feasible to increase the
available supply to the supply area of the Algoa WSS are:
Nooitgedagt Low-Level Scheme (which is currently being implemented) Groundwater Development – Coega Kop aquifer and Churchill Dam area Re-use of water treated to industrial standards – Fish Water Flats WWTW
Successful implementation of WC/WDM
NMBM is implementing its WC/WDM Strategy Action Plan and this intensification of
the WC/WDM program is expected to result in overall savings of approximately 15
million m3/a within 5 years. DWS supports NMBM by giving significant support to
the implementation of their WC/WDM Plan, and by actively pursuing the
implementation of WC/WDM initiatives in other local authorities served by NMBM
and the Algoa WSS, i.e. Kouga Municipality (Jeffrey’s Bay, Cape St Francis,
Humansdorp, Hankey and Patensie).
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