volume 1 - Halifax Regional Municipality

Statement Concerning Halifax Water IRP – Tellus Institute Team
Summary of Halifax Water’s IRP Effort
HW’s development of the Recommended Plan involved a multi-phase analysis. First, Halifax
Water identified three key drivers (growth, regulatory compliance, and asset renewal) and a set
of IRP objectives, as well as major planning assumptions and uncertainties. These were the
inputs from which HW developed an initial set of alternative resource plans to meet the water,
wastewater, and stormwater service needs of the HW service territory through the year 2043. The
alternative plans reflect the mid-range population growth projections that were recently updated
by Halifax Regional Municipality.
HW’s 28 initial resource plans were evaluated not only in terms of 30-year net present value
(NPV) costs, but also the approach and timing of compliance, the degree of overflow control, the
level of asset renewal investment, and the potential environmental and public health impacts.
Based on this analysis, the HW team identified 18 intermediate plans worthy of further
consideration. This involved the elimination of a number of plans as less environmentally
sustainable, the modification of certain plans to ensure consistent wastewater treatment
programs, plus the addition of plans to allow examination of the full range of options for
overflow control plans.
The evaluation of the initial and intermediate plans revealed that asset renewal investments has
the largest impact on cost of the three IRP drivers and accounted for the greatest variation in cost
among the alternative plans. The HW team refined the asset renewal analysis, moving from a
generic approach for all assets to one in which the risks and impacts of failure of each asset class
were considered separately. Based on this assessment a single composite asset renewal strategy
incorporating the risk-based preferred level of asset renewal for each asset class was developed.
Applying the composite asset renewal strategy to the 18 intermediate plans resulted in a set of 10
refined alternative resource plans and considerably reduced the NPV cost variation among the
remaining plans. From the refined plans four plans were shortlisted based on HW’s assessment
that a five-year schedule to meet current wastewater compliance requirements and a ten-year
schedule to implement an overflow control strategy was achievable and appropriately balanced
costs and risks.
From the four short-listed plans a Recommended Plan was selected that incorporates a ten-year
timeframe to meet expected new compliance requirements concerning wastewater nutrient levels
(of particular relevance to the non-Halifax Harbor Solutions Plants that discharge to sensitive
freshwater bodies) and implementation of an enhanced overflow control program that addresses
all overflow locations over the 30-year period. The implementation of the Recommended Plan
implies resource requirements well beyond HW’s existing levels of expenditure and a multiple of
the proposed expenditures in its current Five-Year Capital Plan.
Assessment of Halifax Water’s IRP
This IRP represents significant progress in HW’s understanding of its existing system and its
overall approach to planning. It reflects an intensive effort on the part of the HW team in the face
of significant challenges and provides a solid foundation upon which to build a more
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