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Water Reconciliation Strategy Study for the Large Bulk Water Supply Systems: Greater Bloemfontein Area 30
Unaccounted for Water – Bloemfontein/Mangaung Area (2007/2008 FY)
Input volume
62.04 million
m 3 /a
Authorised
consumption
(estimated)
38.65 million m 3 /a
62.3%
Water losses
(unaccounted for
water)
23.40 million m 3 /a
3. REDUCTION IN BLOEM WATER UAW
Billed authorised
consumption
32.26 million m 3 /a
52.0%
Unbilled authorised
consumption
6.38 million m 3 /a
10.3%
Apparent losses
7 million m 3 /a
30%
Real losses
16.4 million m 3 /a
70%
Billed metered connections
Billed unmetered connections
Unbilled metered connections
(Free Basic Water)
Unbilled unmetered
connections (communal taps)
Unavoidable losses
Illegal connections
Metering inaccuracies
Mains leaks
Reservoirs overflows
Service connection leaks
Revenue
generating water
32.26 million m 3 /a
52.0%
Non-revenue
generating water
29.78 million m 3 /a
48.0%
The bulk water losses for Bloem Water have been calculated as the difference between the volume of
water abstracted from the various sources and the volume of water sold to consumers. Representatives
from Bloem Water have indicated that their total overall losses are in the vicinity of 12% of the bulk water
treated.The table below unpacks the water losses in the bulk water system network of Bloem Water.
Detailed Breakdown of Water Losses in the Bulk System Network of Bloem Water (BW)
(million m 3 /a)
Financial Year
2005 2006 2007 2008 2009
Bulk water supplied from BW's WTWs 53.13 55.27 59.33 62.40 54.82
Less: Bulk meters to MMM 46.20 49.24 52.05 53.99 49.68
Less: Supply to other Local Authorities 2.01 2.34 3.01 3.20 3.29
Bloem Water Conveyance loss downstream of WTP 4.93 3.69 4.27 5.21 1.85
% water loss downstream of WTP 9.6% 7.0% 7.6% 8.8% 3.6%
Bloem Water abstraction from Source 54.91 58.01 62.60 65.87 57.13
Loss in WTW 1.78 2.74 3.25 3.47 2.30
% water loss in WTW 3.2% 4.7% 5.2% 5.3% 4.0%
Bloem Water Total water loss 6.71 6.43 7.52 8.68 4.15
% Total water loss 12.2% 11.1% 12.0% 13.2% 7.3%
It would appear that conveyances losses are in the order of 7% to 9% per annum. Bloem Water has an
active database monitoring system, where the water losses of the different supply systems are monitored
and respective reports are generated. Each of the regional managers within Bloem Water is responsible for
managing their system water losses. The current levels of water losses do not appear inordinately high.
A significant portion of this water loss could also be attributed to the regular bursts which occur on the
Caledon-Bloemfontein pipeline, which is approximately 50 years old.
Interventions Report June 2012