volume 1 - Halifax Regional Municipality

Halifax Water Integrated Resource Plan
Appendices
Table 2.2
Water System Asset Average Age and Fraction Above Design Life
Asset
Design
Asset
Life
(Years)
Variation
Average
Asset Life
(Weighted
Age)
(Years)*
Fraction
Above
Design Life
(Proportion
Greater than
Expected
Life)*
End-of-Period
Asset Age
(Weighted Age)
(Years)*
End-of-Period
Fraction Above
Design Life
(Proportion
Greater than
Expected Life)*
Large WSPs
Small WSPs
Civil - 50
M&E - 30
ICA - 10
Civil - 50
M&E - 30
ICA - 10
A 16.64 0.00%
B 10.7 0% 21.54 0.00%
C 21.58 0.00%
A 15.70 0.00%
B 6.83 0% 15.40 0.00%
C 14.99 0.00%
The results of the analysis for the meters generally show an increase in fraction above
design life for all levels with an attendant increase in average age.
As Halifax Water collects more meaningful asset information, more detailed analysis can
be used to refine the method for determine asset renewal priorities. Presumably this
more detailed analysis will consider accurate age profiles, condition assessment
information, break history and material performance information. However, in order for
this additional level of analysis to be available, significant efforts are needed to gather
the necessary information and make it available and accessible in an appropriate format
(ideally some form of database). This applies to water, wastewater, and stormwater
infrastructure.
The same modeling process was applied to the wastewater and stormwater assets.
Table 2.3 presents the asset renewal costs and renewal rate data while Table 2.4
presents asset design life and average results for these two systems.
The results presented in Table 2.3 shows:
• The range of total wastewater and stormwater asset renewal 30-year NPV costs is
from approximately $886 million for A level wastewater and stormwater system
renewal to $311 million for C level renewal. This corresponds to near tripling (2.9 x)
of costs in moving from C level to A level.
• Approximately 39% - 48% of costs are associated with WWTF renewal activity
depending on level.
• Approximately 22% - 26% of costs are associated with linear assets (i.e. sewers and
forcemains) depending on level.
Revision: 2012-10-29 Integrated Resource Plan –Appendices F-13
October 31 2012 Page 192 of 272