Ellicott City has flooded over a dozen times since founded. If you do a search on ‘history of Ellicott City floods’ you’ll find lots of information - including that the town was deliberately built where it is to take advantage of water power for its mill.
This has nothing to do with climate change; though overdevelopment plays a part:
There are various cities which are built at the bottom of a flood plain, and cities don’t want to admit this and put in massive drainage projects to correct poor planning.
I lived in some German village outside of Kaiserslautern for years. The village was mostly flat, but to the south...there was a massive flat plain (farmers field) which stretched out for around 1,000 acres, and it all sloped toward the village.
One day, I was viewing the weather and there was a particular front coming through at a very slow pace. Over the course of an hour...it probably dumped eight inches of rain in an area of 2 miles by 6 miles. That sloping field got the bulk of it. It flooded out the village and there was no way that the drainage system could handle it. Fair amount of damage to at least sixty houses in the village.
After that, the mayor agreed they needed a drainage system that was made to handle reality.
Maybe after this....Ellicott City will get smart and build a real drainage system.