How can I kill gr in a dry lake cove?

My house is on a cove at the lake. With the drought, the lake in front of my house dried out. It's a meadow now. How can I kill the gr (about 3 feet tall) before the rains fill up the lake again? The lake is a city water supply. The area I'm talking about is about 120' long by 20 feet wide. When the lake is full again, I would like for the lake bottom in front of my house to be sandy, not gry..so swimming will be better.