volume 1 - Halifax Regional Municipality

Statement Concerning Halifax Water IRP – Tellus Institute Team
comprehensive and more fully integrated IRP. However, various data constraints and other
uncertainties, outlined below, limited the extent to which the HW team was able to fully address
certain key issues that could significantly impact the elements, timing, and cost of the
Recommended Plan. As a result, HW’s IRP process was unlike conventional IRP processes in at
least two important respects. First, in a conventional IRP, each of the alternative resource plans
considered meets all compliance requirements from day one and minimization of NPV costs is
by far most the important driver in the selection of a preferred plan. Second, this minimization of
NPV costs approach provides for a relatively straightforward and objective process that is fully
transparent and easily understood.
In the case of this initial HW IRP, the data limitations outlined below required HW to utilize a
complex sequence of steps in which considerable professional judgment was required and the
criteria for selecting the Recommended Plan included consideration of factors beyond NPV
costs. For example, because HW’s wastewater treatment facilities are currently not in full
compliance with Nova Scotia Environment (NSE) requirements, the timing and nature of
wastewater system compliance was an important variable in HW’s alternative plans. In addition,
the lack of adequate information about existing system conditions as well as regulatory
uncertainty led to the inclusion of other variables related to the degree of overflow control, the
level of asset renewal investment, and potential environmental and public health risks. The
consideration of multiple criteria in selecting the Recommended Plan not only made HW’s initial
IRP process more complex than a conventional IRP, the need for considerable professional
judgment (e.g., concerning the appropriate timing of compliance, the degree of overflow control
and related risks) made it less transparent.
The overriding limitation of the IRP relates to the lack of sufficient information. For example,
while it is abundantly clear that the wastewater system is in need of substantial repair, upgrades
and renewal, it is not possible using existing asset condition data to estimate such important
measures as the likelihood of pipe failure or the impacts of overflows on receiving waters. Such
information is necessary to identify optimal asset renewal strategies and ultimately the
prioritization and timing of individual projects. We note that while this information could not be
developed within the time frame of this initial IRP, HW has recently completed an Asset
Management Assessment Program that provides a detailed multi-year roadmap to address this
gap.
Similarly, sufficient information is not currently available to evaluate the effectiveness of
demand management strategies, particularly for the wastewater system, such as inflow and
infiltration (I/I) reduction and combined sewer separation. The initial level of analysis presented
in the IRP suggests that I/I and other demand management efforts may very well be feasible and
cost effective in some areas of the HW system. A better understanding of the potential flow
reductions from demand management efforts could have important implications for the technical
approach, magnitude and timing of the capital programs required to meet HW’s service needs as
well as for the asset renewal strategy. We note that HW has outlined a proposed I/I Reduction
Pilot Program in the Recommended Plan (as well as an overall Wet Weather System Plan). We
support this proposal and urge HW to develop a detailed scope of work, methodology and
schedule to plan and implement the I/I Reduction Pilot Program in an expeditious manner.
October 31 2012 Page 270 of 272
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