invasive groundcover for wet area

I need a ground cover for the storm water retention area beside our house. It is in the corner of our subdivision. The 70' x 100' area fills with water when it rains and slowly drains. It does not hold water, but it is frequently very wet. It is not a pond. Someone suggested Chameleon Houttuynia, but there are so many negative comments about the invasiveness and smell that I am afraid to try it. The County mows the area once or twice a year, so it needs to be able to withstand mowing. Right now we have cattails, thistles and weeds. Mosquitoes are also a problem. The sides are very steep and difficult to mow. We are in north-central Ohio, zone 5b. Any advice?

Groadruck, How about Artemisia Vulgaris Limelight? It's varigated and pretty. I hear it can be invasive in warmer climates.

Thanks for the suggestion, but I am afraid that 4 to 6 feet tall will not work in our application. I think I might try Golden Moneywort. I'm just not sure if it will be invasive enough to crowd out the weeds. Do you have any experience with it?

No Groadruck< I don't. The Artemisia only gets about 2' tall. Most Artemisias grow very quickly and form large patches. Most of them are silver colored. The limelight is bright green with creamy/yellow varigation.

That one spreads far & wide. I'm not sure you'd really want to plant it
anywhere.