A red-necked grebe was rescued in Columbia earlier this month. That link to the Howard County Bird Club page shows some photos and a short video of the bird in the wildlife rehabilitator's tub before it was released at Sandy Point. Another red-necked grebe has been staying at Lake Centennial recently. Grebes are not agile at all on dry land, and a couple of species can't even walk if trapped on land. They need lots of open water.
Lake Kittamaqundi, close to my home, gets the small but rather cute pied-billed grebe during the spring and fall migrations, and the bird club has shown me a horned grebe during a walk at Wilde Lake.