Thank you for writing.

Here is some information. Without a picture, I am assuming that you have identified the plant.

https://apps.extension.umn.edu/garden/diagnose/weed/grass/creepingbentgrass.html

Start with improving the lawn environment.  Bentgrass does better on overwatered lawns which is the norm in the city.  
https://apps.extension.umn.edu/garden/diagnose/weed/idlist.html#CBentgrass

https://extension.umn.edu/lawncare/water-saving-strategies-home-lawns#:~:text=To%20encourage%20rooting%20and%20drought,a%20half%2Dinch%20of%20water 

The chemical controls are non-selective and kill all plants or are toxic to waterways.  I suggest consultation with a lawn service. The University is not allowed to recommend specific venders.

Thank you for writing back. It is quite possible that a bentgrass species was part of the seed mix in your yard.  https://www.gardeningknowhow.com/lawn-care/specific/bentgrass/growing-bentgrass-in-lawns.htm 

Monoculture lawns, especially trying to focus on blue grass for example, are not sustainable. http://ci.chanhassen.mn.us/DocumentCenter/View/4789/Choosing-Lawn-Grasses-UMN-Extension?bidId=   https://extension.umn.edu/lawn-care/seeding-and-sodding-home-lawns 

For this reason the best approach is to focus on aeration, not overwatering, and overseeding with grasses that you want to select for.  There is increased interest in fine fescues although they do not look like the traditional idea of a nice lawn.

I hope this helps.