The Impact Assessment also pointed out that a sizable active littoral zone (estimated to be at least 10m to 20m wide) appears to exist at the site as a product of the shallow local bathymetry, the prevailing winds, the orientation of the shoreline, and the unprotected, eroding characteristic of the shoreline that fronts the WDBA and Windsor Port Authority lands.

We noted that the proposed BBA infill had a high probability of disrupting the ongoing coastal processes and littoral transport patterns in the vicinity of the Broadway Drain, which would serve to accelerate the local rate of net littoral transport from south to north, and thereby further increase the rate that sediment collects near the mouth of the Broadway Drain (as well as within the proposed embayment area to be created on the BBA lands).

Finally, we noted that the proposed BBA infill had the real potential cause greater amounts of organic flotsam and jetsam to collect near the mouth of the Broadway Drain and in the proposed embayment, as well as increase the potential for flow ice to accumulate in the area. It was noted that the potential for increased accumulation of river ice has the potential to increase the flood risk on the Broadway Drain during late winter rainfall events that occur before ice out. This potential would be elevated during periods of low water levels in the Great Lakes.

In recognition of the increased potential for sedimentation of the drain outlet and/or the accumulation of floating debris and river ice at the drain outlet, the training jetties at the outlet of the Broadway Drain need to be appropriately extended or modified from what was originally proposed, in order to mitigate the aforementioned potentials.

C. Proposed Design Alternatives

This section highlights the key characteristics and principal design basis of the two alternative drain outlet configurations, namely:

a) Alternative A – consisting of an outlet design that is needed to accommodate the infill at the BBA property as originally proposed; and

b) Alternative C – consisting of an outlet design that assumes that minor adjustments can be made to the BBA infill.

Note: Alternative B was discarded from any further consideration subsequent to issuance of the Impact Assessment.

i) Alternative A

For this design, the south and north training jetties have been substantially extended (approximately 27m and 37m respectively) from the original through the predicted eddy or recirculation zone that would be created by the infill. The general scope of the outlet configuration is depicted in Figure 1 (attached hereto).

Design Summary for Broadway Drain Outlet – January 12, 2016

Gordie Howe International Bridge