volume 1 - Halifax Regional Municipality

Halifax Water Integrated Resource Plan
Appendices
• The current annual expenditure as a percentage of the asset value was based on the
asset renewal expenditures provided in the Five-Year Capital for 2012 to 2017. It was
assumed that the budgeted amounts are indicative of current asset renewal
expenditures.
• Some special assets with significant site-specific conditions affecting renewal costs
such as reservoirs or dams were not modelled but rather subjected to individual
analysis to estimate required renewal over the 30-year period. These were high-level
estimates. Specific detailed evaluations should be made for each of these structures
to establish current condition and replacement requirements.
Based on the below, Table 2.1 shows the following:
• The range of total water asset renewal 30-year NPV costs is from approximately
$581 million for A level water system renewal to $312 million for C level renewal.
This corresponds to near doubling (1.9 x) of costs in moving from C level to A level
• Approximately 25% -30% of costs are associated with WSP renewal activity
depending on the level of renewal.
• Approximately 42% -53 % of costs are associated with linear assets (i.e. distribution
and transmission mains) depending on level of renewal.
• The modelled renewal rates significantly exceed the current renewal rates shown in
the Five-Year Capital Plan for complex facilities such as WSPs, pumping stations,
valves and pressure reducing valves (PRVs).
• Current renewal rates for distribution mains are less than C level while current rates
for transmission mains fall between B level and A level.
• Current renewal for metering significantly exceeds modelled rates at all levels.
As noted below, the asset renewal modeling used some simple rules based on asset age.
For purposes of evaluating asset renewal effectiveness, two metrics were employed –
average asset life at the end-of-period and the fraction of assets above design life.
Revision: 2012-10-29 Integrated Resource Plan –Appendices F-9
October 31 2012 Page 188 of 272