Flooding like that on July 1st may mean floodways?

 

5800 reports of flooded basements stemming from Canada Day rainfall of 167 mm.

What can be done? Most believe there are more storms like this to come in the future.

Floodways are engineered diversion channels, bypasses, or designated floodplain zones that safely redirect excess water away from vulnerable urban areas. They prevent billions in damages while frequently providing ecological and recreational benefits. [1, 2, 3, 4]

Floodway examples include:

1. The Red River Floodway (Manitoba, Canada)

A 47-kilometer artificial channel east of Winnipeg that diverts floodwaters from the Red River around the city and safely rejoins the river downstream. [1, 2, 3, 4]

• Why it’s successful: Originally dubbed "Roblin's Folly," it has been used dozens of times since its completion in the 1960s, preventing tens of billions of dollars in flood damages. During non-flood seasons, sections of the floodway are used for agriculture, recreation, and wildlife habitats. [1, 2, 3, 4, 5]

2. The Yolo Bypass (California, USA)

A massive 24,000-hectare engineered floodplain in the Sacramento River Valley. During high-water events, specialized weirs spill water into this bypass rather than letting it flood the city of Sacramento. [1, 2, 3]

• Why it’s successful: The bypass safely conveys roughly 80% of the region's major flood discharge. In the dry season, it serves dual purposes as productive agricultural land (primarily rice) and a critical wetland habitat for migratory birds and native fish. [1, 2, 3, 4]

3. The San Antonio River Tunnel System (Texas, USA)

An underground tunnel system built beneath the city of San Antonio to catch and divert floodwaters away from the highly popular, vulnerable downtown River Walk. [1, 2, 3]

• Why it’s successful: Instead of destroying the city's famous above-ground aesthetics, the underground tunnels safely capture excess runoff. This protects both residents and the tourism industry without disrupting the urban core. [1, 2, 3]

4. The Salmon River Management Plan (Nova Scotia, Canada)

 A designated "floodway" and "flood fringe" with a two-zone approach.

• Why it’s successful: It acts as a successful policy-based floodway model rather than a massive concrete project. Municipalities restrict development in the high-risk, central floodway, while allowing performance-based "cut and fill" developments in the flood fringe. This prevents life-threatening property damage while allowing the community to safely adapt. [1, 2, 3]

5. Setback Levees along the Elbe River (Germany)

The practice of relocating traditional levees further away from the river channel, effectively creating a wider natural floodway between the levees. [1, 2, 3]

• By widening the space the river can occupy, it lowers peak flood stages for nearby towns while simultaneously restoring rare floodplain forests and naturally improving water quality. [1]

The combined sewer systems in Manor Park and West Rockcliffe are problematic too. 

Infrastructure is behind the curve.

Possible work around also include:

• Dedicated Spreading Grounds: Converting local parks or low-lying areas into dual-use spaces (like L.A.'s Tujunga Spreading Grounds) that act as recreational fields dry, but safely pool massive amounts of street runoff during an emergency. [1]
• On-Site Retention Ordinances: Mandating that new commercial developments build underground storage tanks or permeable surfaces to capture rain where it falls, easing the instant pressure on municipal sewers. [1, 2]

• "Sponge City" infrastructure  to prevent urban flash floods
• The infrastructure upgrades currently being debated by Ottawa City Council
• Replacement of neighborhood combined or the preferred 'separated' sewer system

The flooded Queensway relies entirely on underground storm sewers and high-capacity catch basins to pump or drain water up and out into nearby creeks (like Watts Creek or Pinecrest Creek). 

On Canada Day, those local creeks and underground drainage networks were completely overwhelmed. The water on the highway had nowhere to flow because the pipes it connects to were already entirely full of water from surrounding neighbourhoods like Queensway Terrace North.

Tokyo vs. Ottawa: Different Scale, Same Strategy

Tokyo's G-Cans (officially the Metropolitan Area Outer Underground Discharge Channel) is the world's largest underground floodwater diversion facility. Located in Kasukabe, Saitama Prefecture, 50 meters below ground, it protects the city from typhoons and heavy rains using 6.4 km of tunnels and five massive, 65-meter-deep silos. [1, 2]

The central attraction is the colossal pressure-adjusting tank—a cathedral-like space held up by 59 massive concrete pillars—often dubbed the "Underground Temple". [1]

Here are the specific details to visit:

• Location: 720 Kamikanasaki, Kasukabe, Saitama. It is roughly a 60–90 minute trip from central Tokyo, reachable via the Tobu Noda Line to Minami-Sakurai Station (about a 3 km taxi or walk from the station).

While Ottawa does not need a $2.6 billion megastructure, the engineering philosophy behind Tokyo's vaults is exactly what is needed for the Queensway corridor: [1]

• What Tokyo Does: G-Cans captures water when the local rivers and storm drains overflow, holding up to 670,000 cubic metres of water until the main river levels drop. [1]
• What Ottawa Needs: A localized version of this. Instead of a multi-kilometer tunnel network, a highway like the Queensway requires a compact, targeted subterranean concrete retention vault built right within the highway shoulder or nearby transit right-of-way. It doesn't need jet engines; it just needs enough underground volume to hold the surface runoff until the municipal pipes clear.

Tokyo proved to the world that when surface space is non-existent and property rights are dense, the only viable engineering solution is to move the water straight down. [1]

How many more floods must occur before a decision is made?