DRINKING WATER AND WASTEWATER RELATED CORROSION COST
Saudi Arabia is one of the driest regions in the world, with no perennial rivers. Water is obtained
from following four distinct sources:




non-renewable groundwater from the deep fossil aquifers
desalinated water
surface water
renewable groundwater from shallow alluvial aquifers
Only the last two sources are renewable. Their volume, however, is minimal. Current levels of
groundwater abstraction far exceed the level of natural recharge: In a way groundwater is being
“mined”. For example, the Al-Hasa aquifer in the Eastern Province experienced a drop of 150
meters over the past 25 years. Since the usable volume of the aquifers is not known, it is not
clear how long groundwater mining can be sustained.
Saudi Arabia is the largest producer of desalinated water in the world according to Saline Water
Conversion Corporation (SWCC) annual report 2008 [1]. There are thirty desalination plants
spread on the east and west coasts of Saudi Arabia. Of these, six desalination plants are located
on the coast of the Arabian Gulf and twenty four on the Red-sea coast. The sweet water
production of these plants was 1,055,681,743 cubic meters in year 2008 approximately 1% less
than the previous year (1,066,825,977 cubic meters in 2007). The water production was around
3.3% more in year 2007 compared to that in 2006 (~1,050 million cubic meters). Saudi Arabia is
the third largest consumer of water per capita in the world i.e. 235 liters per capita per day.
In the next several years, it also is expected to become the third largest water reuse market in the
world after the United States and China, according to the Sustainable Water Alliance. Currently,
only about 18% of the 1.84 million m³ of wastewater the country processes daily is reused. There
are 33 wastewater treatment plants with a capacity of 748 million cubic meters per year, and 15
more are under construction. Much of the treated wastewater is being reused to water green
spaces in the cities (landscaping), for irrigation in agriculture and other uses. Water reuse in
Saudi Arabia is growing, both at the level of buildings and at the level of cities. For example,
ablution water in mosques is being reused for the flushing of toilets [2]. Total municipal water
use in Saudi Arabia has been estimated at 2.1 billion cubic meters (BCM) per year in 2004, or
9% of total water use. Agriculture accounts for 88% of water use and industry for only 3%.
Demand has been growing at the rate of 4.3% per annum (average for the period 1999-2004), in
tandem with urban population growth (around 3%). It is tentatively estimated that average water
consumption for those connected to the network is about 235 liters per capita per day, a level
lower than in the United States [3].
Corrosion cost estimation
The total cost of corrosion will be estimated by assuming that at least 50 percent of the
maintenance and operation costs are to replace aging (corrosion) infrastructure, while the other
50 percent would be for system expansion. The operation and maintenance costs include
expenditures related to the water transmission and distribution, water treatment, water storage,
water source, and other water needs.
Several studies show that the direct cost of maintenance and repair of water pipes, and repaving
after work is done is approximately 50 percent of the total budget of water departments [4]. The
total annual direct cost of corrosion for the nation’s drinking water and sewer systems, as per
international practices, is contributed to by:





the cost of replacing aging infrastructure
the cost of unaccounted-for water through leaks,
the cost of corrosion inhibitors,
the cost of internal mortar linings, and
the cost of external coatings and cathodic protection
Specifically, the major cost categories will include the following cost items:

Drinking water infrastructure network cost data which include:
 current annual cost of investment, (Cost X1 billion/year)
 operation and maintenance cost and (Cost X2 billion/year)
 financing of the national drinking water system (Cost X3 billion/year)

Waste water infrastructure network cost data which include:
 current annual cost of investment, (Cost Y1 Billions/year)
 operation and maintenance cost and (Cost Y2 Billions/year)
 financing of the national waste water system (Cost Y3 Billions/year)
The cost of corrosion inhibitors added to the drinking water is a percentage of the total treated
water cost. American Water Works Association (AWWA) [5] estimated that the annual costs for
corrosion inhibitor treatment ranges from $1.00 to $1.50 per residential consumer. Nationally, it
is estimated that approximately 15 percent of the treated water is lost. Studies by AWWA [5]
show that the cost for water pipe rehabilitation by cement mortar lining ranges from 13 percent
to 41 percent of the costs of total pipe replacement. Several studies show that the direct cost of
maintenance and repair of water pipes, and repaving after work is done is approximately 50
percent of the total budget of water departments.
Cost of corrosion for year 2007 and 2008
According to annual report [6] in year 2007 the expenditure related to spare parts was SR
383,005,211, on maintenance SR 135,335,700, and on rehabilitation of the facilities SR
277,215,183. Similarly the respective costs related to spare parts, maintenance, and rehabilitation
in year 2008 were S.R560,587,051, S.R156,512,184, and S.R 272,050,950, respectively. The
cost data given in column 2 of Tables 1 and 2 was obtained from SWCC annual reports [6 and
1]. The corrosion cost given in last column of the Tables 1 and 2 were taken as the 50% of the
items given in column 1. The maximum corrosion cost was occurred on spare parts in year 2007
(around 48% of the total corrosion cost) and 2008 (around 57% of the total corrosion cost), as
can be seen from Tables 1 and 2 respectively. The least corrosion cost was attributed towards
maintenance in both the years i.e. 17% and 16%, respectively. The remaining cost of corrosion
of 35% and 27% corresponding to 2007 and 2008, respectively, in water sector was attributed to
rehabilitation of the water infrastructure, plants, pipelines, etc.
Table 1. Cost of corrosion related to water sector for year 2007.
Spending in
Cost of
Item
2007
Corrosion
Spareparts
383,005,211
191,502,606
Maintenance
135,335,700
67,667,850
Rehabilitation
277,215,183
138,607,592
Total - 2007
795,556,094
397,778,047
Table 2. Cost of corrosion related to water sector for year 2008.
Spending in
Cost of
Item
2008
Corrosion
Spare parts
560,587,051
280,293,526
Maintenance
156,512,184
78,256,092
Rehabilitation
272,050,950
136,025,475
Total - 2008
989,150,185
494,575,093
Data needed:
 Plant name and address
 Technology used
 Plant capacity
 Plant commissioning date
 Length of water distribution pipe line
 Length of sewage system pipe line
 Total annual consumption of water
 Per capita water consumption
 Length of water distribution pipe line
 Drinking water infrastructure network cost data which include:
 current annual cost of investment
 operation and maintenance cost and
 financing of the national drinking water system
 Sewage water infrastructure network cost data which include:
 current annual cost of investment
 operation and maintenance cost and
 financing of the national waste water system
References
1. Saline Water Conversion Corporation (SWCC) annual report 35, 2008, Riyadh, Saudi
Arabia.
2. Walid A. Abderrahman:Water demand management in Saudi Arabia, in: Water Management
in Islam, IDRC, 2001, Edited by Naser I. Faruqui, Asit K. Biswas, and Murad J. Bino
3. W.A. Abderrahman:Water Management in ArRiyadh, International Journal of Water
Resources Development, Vol. 22, No. 2, June 2006, p. 281.
4. Michiel P.H. Brongers, Drinking Water and Sewer System, Appendix – K, CC Technologies
Laboratories, Inc., Dublin, Ohio
5. American
water
works
Association
(AWWA),
th
http://www.awwa.org/index.cfm?showLogin=N (accessed on 27 December 2010)
6. Saline Water Conversion Corporation (SWCC) annual report 34, 2007, Riyadh, Saudi
Arabia.