volume 1 - Halifax Regional Municipality

Halifax Water Integrated Resource Plan
Recommended IRP and Analysis
Figure 6.5
Dartmouth WWTF Demand Reduction
In order to assess the potential benefit to cost relationship associated with the demand
reduction activity the following assumptions were made:
• The bulk of the cost of the 30% future water/wastewater demand reduction would
be incorporated into the cost of the new dwellings and buildings (through low-flow
appliances and fixtures) and would not impact on the IRP capital requirements.
• The cost of the demand reduction for existing water/wastewater usage would be
small and would be largely achieved through existing public education programs
The cost of the I/I program could not be determined precisely due to the absence of
Halifax data. Instead a high-level analysis approach was based on the large scale,
well resourced, multi-year program in King County, Washington.
The King County program examined a wide range of on-lot and public system measures
to achieve flow reductions. The overall goal of the program was a reduction equivalent
to 30% of existing I/I rates. The program considered numerous major expansions of
wastewater collection, conveyance and treatment facilities. An analysis of the King
County costing data for I/I reduction projects was carried out for the IRP and is
presented in Figure 6.6. The costs were indexed from 2005 to 2012 using the ENRCCI.
The costs include a construction cost multiplier accounting for engineering and
contingencies among other factors.
Revision: 2012-10-29 Integrated Resource Plan 83
October 31 2012 Page 116 of 272