I walked past a garden today that had drainage holes at the bottom of a brick retaining wall for land drainage. I believe this is normal construction. However, a fair bit of water had seeped out and formed a really lethal ice patch about 6ft wide across the full width of the road - just before where the side road meets the main road. If you were driving and you slowed to pause to look along the main road, I don't doubt the car would slide. If this happened and you crashed with the main road traffic, could the garden owner be liable?