In the early 1900s, sand-cast iron pipe was used almost exclusively for water
distribution piping in the City of Edmonton, Alberta, Canada. During a period of
rapid growth following World War II, a significant amount of cast iron pipe was
installed, most of which was the spun-cast type. An increasing break frequency
led to the decision to discontinue the use of cast iron pipe in 1965. The break
frequency continued to increase throughout the 1970s and early 1980s and limited
replacement of the most problematic sections of cast iron pipe was performed. In
1985, a peak of 1,600 water main breaks were recorded on 758 miles of pipe
resulting in significant inconvenience to many customers. In response to the
problem, a surcharge was introduced to the water bills of all customers in the
City of Edmonton to specifically fund a cast iron water main replacement program.
By the end of 1997, the capital program funded through the surcharge had expended
over $70 million which resulted in a decrease in the length of cast iron water
main to approximately 544 miles and a corresponding decrease in the annual number
of breaks to 489. Aqualta, Edmonton's privatized water utility, is now shifting
from a reactive to a proactive approach to managing the remaining cast iron pipe
network. Alternative technologies such as cathodic protection are now being
applied to some problematic pipe to reduce the rate of deterioration. The utility
is also looking to the use of non-destructive testing for evaluation of pipe
condition and artificial intelligence computer models for prediction of failure
likelihood. This paper discusses Aqualta's cast iron water main replacement
program. Includes reference, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.2 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 12 |
| Published : | 01/01/1999 |
