volume 1 - Halifax Regional Municipality

Halifax Water Integrated Resource Plan
Appendices
to control only those 28 overflow locations that are expected to experience growth in their
tributary sewersheds and only to a level sufficient to offset the effects of growth.
Halifax Water has produced an evaluation of the environmental and public health risks
associated with known overflow locations. It has categorized each location according to
the categories presented in Table 2.9.
Table 2.9
Risk Category
A
B
C
D
E
Receiving Water Risk Categories
Risk Description
Drinking water
Supervised HRM beach or on-ground with high potential for human contact
Known unsupervised swimming areas and designated recreational areas (boat clubs, parks etc.)
Other freshwater bodies and/or ground with low potential for human contact
Other marine bodies
The average year overflow volumes associated with current conditions, future growth
with no controls, and future growth under the RWWFP preferred scenario are
summarized for the 28 overflows impacted by growth in Table 2.10. The Table also
includes the 31 non-growth impacted overflow volumes for the same scenarios as well
as differentiating. All overflow locations by risk level.
Table 2.10
Average Year Overflow Volumes
Category
Receiving
Water Risk
Level
Number of
Outfalls
Baseline
(1000 m 3 /yr.)
Growth No
Controls
(1000 m3/yr.)
Preferred
RWWFP
(1000 m 3 /yr.)
E 12 7,891 8,021 9,47 1
D 0 0 0 0
Non-Growth
Outfalls (31)
C 6 74 74 74
B 13 697 696 667
A 0 0 0 0
Total 31 1,560 1,572 1,688
E 15 6,772 10,935 5,449
RWWFP
Growth
Impacted
Outfalls (28)
D 4 46 355 43
C 5 935 4,895 646
B 4 29 51 28
A 0 0 0 0
Total 28 7,782 16,236 6,166
Total System Outfalls 59 9,342 17,808 7,854
Revision: 2012-10-29 Integrated Resource Plan –Appendices F-23
October 31 2012 Page 202 of 272