Water levels in Winnipeg are measured in "feet James," the level above the normal winter ice level as measured at a gauge on the Red River east of James Avenue in the Exchange District, just downstream of The Forks where the Red and Assiniboine rivers meet.
Zero feet James is the baseline winter ice level on the Red River at James Avenue. This is the baseline for measuring river levels in Winnipeg.
In the summer, the St. Andrews Lock and Dam regulates water levels to try to maintain 6.5 feet James.
The walkway elevation at The Forks is 8.5 feet James. It was placed at this elevation on the expectation the walkway would sit above the river most of the summer.
When water levels get to around 15 feet James, we’re informally in minor flood territory. That’s when the city starts to take proactive flood-mitigation measures, such as closing drainage gates to prevent stormwater drains from being inundated with river water.
If James Avenue datum starts flirting with 20 feet, that is considered a major flood level and you’ll start seeing sandbags in vulnerable areas.