volume 1 - Halifax Regional Municipality

Halifax Water Integrated Resource Plan
Integrated Resource Plan Drivers and Objectives
4.3.3 Wastewater Overflows
At present, Halifax Water is required by NSE to monitor and report on CSOs and SSOs.
NSE has also indicated that the impact of any growth on overflows will need to be
mitigated so that there is no increase in overflow frequency or volume. This is the basis
for the overflow control measures proposed in the RWWFP.
Halifax Water is also taking current actions to mitigate overflows. The Five-Year Capital
Plan includes a number of projects addressing wet weather flow issues that includes
screening of CSO discharges, a number of wet weather flow (I/I) reduction projects, as
well as the overflow monitoring program.
Sections 17, 18, and 20 of the recently implemented WSER reinforce the monitoring and
reporting requirements but require no more action for the present. Discussions with NSE
should be used to verify whether any specific requirements have changed and to confirm
what additional measures NSE will require over and above what is stipulated in the WSER.
As discussed in Section 3 and above, an Enhanced Overflow Control Program has been
included within the IRP to address these future overflow control needs. The Enhanced
Overflow Control Program is presented in Volume 1 Appendix F.
4.3.4 Stormwater System
Under current requirements there are no regulatory compliance issues with respect to
the stormwater system.
The main future concerns are the impacts of stormwater on receiving water quality and
the impacts related to flow volumes and velocity (i.e. flooding and erosion). A report 25
commissioned by HRM noted that stormwater runoff could negatively affect both the
quality and quantity of area water resources. With respect to water quality, the report
stated that stormwater runoff can lead to increased loadings of toxic substances, such
as heavy metals and hydrocarbons, increased nutrient loadings from fertilizers and
organic debris, increased levels of bacteria from animal waste, increased sedimentation,
increased salinity from road salt, lower levels of dissolved oxygen, increased stream
temperature, and reduced biodiversity. Water quantity impacts resulting from
stormwater runoff cited in the report included increased volume and velocity of
watercourses in developed areas and decreased base flows in receiving waters.
The Regional Municipal Planning Strategy 26 commits HRM to preparing a Regional
Stormwater Functional Plan (RSWFP), which is expected to consider:
• Methods to reduce increased stormwater flows caused by development with
consideration given to problems associated with downstream flooding, stream bank
25 Water Resource Management Study, Dillon Consulting Ltd., 2002
26 Regional Plan, Halifax Regional Municipality, 2006
Revision: 2012-10-29 Integrated Resource Plan 39
October 31 2012 Page 72 of 272