Luckily the lakes are still a little low after 3 summers of flash drought and a mostly snowless winter, so they can take some runoff. In 2019 Minnehaha Creek was flowing over the Grays Bay Dam spillway at Lake Minnetonka for a few weeks, it caused minor flooding along the trails at the lake down the block from my house. (Nokomis) The Mississippi River downstream from St. Anthony’s Falls is in a gorge which acts like a giant storm sewer for the cities, but if rainfall rates are high enough there will definitely be urban flood potential. As you mentioned the suburbs have exploded with growth over the past 30 years so newer built areas will definitely be put to the test. I did the geotech work on a massive flood control project that MNDOT finished up last year, time to put this system to the test.
https://www.kare11.com/article/news/local/mndot-builds-massive-storm-drainage-tanks-along-35w/89-461d7b05-01d7-4b6d-9181-c0a7bf753fe8