Construction of the Neebing-McIntyre Floodway was completed in 1984 by the Lakehead Region Conservation Authority with a final cost of $15-million dollars. The Floodway was constructed to address flooding in the lower Neebing River and Intercity Area of the City of Thunder Bay.
The main features of the Floodway include:
- Diversion Structure at Ford Street
- Diversion Channel
- Sediment Trap at Balmoral Street
- Sediment Trap at CPR Bridge
- Widened and deepened Floodway Channel to Lake Superior
- Outlet into Lake Superior
The design capacity of the Floodway is to provide protection up to and including the Regional Storm. The construction of the Floodway has resulted in significant development in the Intercity Area.
The Floodway provides protection by limiting flow volumes in the lower Neebing River to approximately 29 cubic metres per second. The flow in the lower Neebing River is controlled by the Diversion Structure which controls flows through the use of a 2.5 x 2.5 metre opening in the structure. Excess flows are diverted down the Diversion Channel to the widened deepened Neebing-McIntyre Floodway Channel.
Since the opening size is fixed, some diversion occurs almost every year with upstream flows as little as approximately 10 cubic metres per second.
During flood events the Floodway operates without any required actions. The Diversion Structure limits flows down the lower Neebing River and diverts excess flows into the 1.5 kilometre Diversion Channel which directs excess flows to the widened, deepened Neebing-McIntyre Floodway to Lake Superior.
In 1941, the region was hit by a fierce storm which caused extensive flooding on the Neebing River. The flood waters rose to the point where they overflowed into the McIntyre River. In an attempt to deal with flooding problems, the Neebing Valley Conservation Authority (NVCA) was created in 1954. In 1963, as a result of expansion, the NVCA became the Lakehead Region Conservation Authority (LRCA). Since then, the Lakehead Region has received several major rainstorms. The first three major storms, occurring in 1968, 1971 and 1977, caused the Intercity area to experience major damage due to flooding. Such was not the case in 1997, 2008 and 2012 thanks to the construction of the Floodway. The major storm in 2012 resulted in extensive damage; however the Floodway itself was fully functional and worked exactly as designed resulting in no riverine flooding in the lower Neebing River or Intercity area.
The Neebing-McIntyre Floodway also serves as a recreational attraction. Various paved trails along the floodway and diversion channel link to City of Thunder Bay trail network. There are also some fantastic wildlife viewing opportunities along the Floodway, including waterfowl, amphibians, groundhogs, songbirds and more!