How do you protect front lawn from cars?

Hello Ottawa residents, I am wondering how do you protect your front lawn area from cars/trucks? We have a corner plot with no backyard. Only front and side yards. Last summary and this winter I saw cars and trucks driving over the corner of the front lawn. Which essentially destroyed some small plants we had planted there. Now it seems the cars and trucks driving over half the front lawn with snow cover. I am waiting for a nasty surprise when the snow thaws. It is part of city's easement and there seems to be restrictions on what we can place.

Anyone with similar problems or any creative solutions?