As noted in Section 2.3, the recommended improvements were initiated and substantially completed in 2017, prior to completion of the Engineer’s Report, in order to allow development of the PAR and the remainder of the early works associated with construction of the GHIB. Further improvements were undertaken in 2018 to repair some minor bank instability that developed shortly after completion of the initial improvements.

The following summarizes the improvements that have been implemented and that define the new Broadway Drain.

a) Approximately 780 metres of the upstream reach of the original Broadway Drain, from Ojibway Parkway to the existing Sandwich Street was abandoned and replaced with a concrete box culvert that was designed by Stantec as part of the Perimeter Access Road project. This segment of the former drain was replaced with a municipal sewer, and will no longer form part of the Broadway Drain.

b) Three segments of trapezoidal earth-lined channel (totalling 555m in length) with a bottom width of 1.5m and side slopes of 3(hor.):1(vert.) were excavated downstream of the above-noted concrete box culvert. The new drain segments are approximately 3.5m deep at the invert, and have typical top widths ranging from 16 to 23m. Due to the proximity of the new channel to other critical infrastructure (e.g., gas main, new roadway, etc.) and private property, rock slope protection has been installed along the entire north bank of the new earth-lined channels, in order to mitigate the potential for channel bank erosion and long-term recession.

c) The most westerly 190m of the Drain, from Sta. 0+000 to Sta. 0+190 was routed through a 30.5m wide corridor owned by Transport Canada. The typical top width of the drain through this reach ranges from 19m to 20m, allowing for a 6m-wide maintenance corridor along the north side of the drain. The additional 5.0m to 5.5m width through this segment was utilized to alter the alignment of the south bank of the channel to create a series of promontories and intermittent benched areas. The elevation of the benched portion of the south channel slope was intentionally varied in order to allow suitable degrees of submergence at varying Detroit River water levels. The purpose of the benched areas is to create additional habitat diversity along the drain – particularly spawning habitat for Northern Pike

d) In order to avoid impacting lands owned by the WPA, an alternative channel section consisting of an open, steel-lined rectangular section was constructed from Sta. 0+201 to