Perfect Seawall — Incredible Retaining Walls We have a house on Gravel Lake that needed a seawall and a series of retaining walls to hold back a 30 drop from the house to the shoreline. Not only was the seawall from First Impression perfectly straight, beautiful to look at and totally durable, but the retaining walls are amazing. The business owner, Bill, built in stairs and landings as well as a fire pit to make the walls serve double duty: it’s a retention system with two optional outdoor areas to enjoy the lake from. As you look at the house from the water, I’m the King of the Lake.