updated planning report updated planning report - City of Guelph

Updated Planning Report September 2008
Proposed Lafarge/Silvercreek Development
5.4.4 Addendum III, Response to Guelph EAC Comments April 9, 2008
This further addendum focuses on technical responses to the various issues raised by
Guelph EAC on April 9, 2008. Among the matters addressed are the following:
• the overlaying of certain features on the grading plan, including the creek, setbacks
from the creek banks, location of the stable top of bank, the setback from steep
slopes, development limits, revised pre- and post-development floodplains, setback
from the watercourse, and location and setbacks to the drainage swale;
• reiteration of the 2005 locally significant bird species on the revised development
plan overlay, with similar impacts;
• discussion of some of the design details of the proposed community park;
• the previous hazard lands boundary for both sides of Howitt Creek is
superimposed on the revised development concept, and the rationale for
recommended stream setbacks (development limits) is discussed, based on
“…bankfull channel width...”, resulting in average stream buffer widths of 18.9m on
the west side of the creek, and more than 30m on the east side;
• tree conservation and preservation measures;
• the location and design of the stormwater management facility in proximity to the
creek, in relation to the revised development concept;
• a list of impacts to be addressed in greater detail in a subsequent “Environmental
Implementation Report”, as development design is refined; and,
• a summary of details related to mitigation and compensation.
5.4.5 Addendum IV, Revised Impact Assessment Associated with Revised Storm
Water Management Plan, August 2008
This is the most recent addendum, specifically arising from the altered SWM approach
and details summarized in Section 5.3 of this planning report.
The report concludes that the revised stormwater detention facility is intended to reduce
existing flows in Howitt Creek, and thus “…is not expected to affect channel morphology,
and will likely reduce erosion rates downstream of the subject property.” Companion
technical recommendations are provided to address existing erosion and avoid
exacerbating it.
From a fisheries perspective, the report concludes that the new SWM plan “…will
improve fish habitat in Howitt Creek by buffering flash flows and removing a barrier to
fish passage.” It also notes that standard mitigation methods can be used to avoid fish
habitat impacts in most cases, with compensation options available on this site to
enhance fish habitat where impacts can’t be avoided.
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