The present disclosure relates to methods of stabilizing a seawall and reducing erosion around a seawall. Disclosed herein are methods of reducing erosion around a seawall, comprising injecting an amount of a sealing material to an injection depth at each of a plurality of spaced locations along a landward side of a new seawall. Also disclosed herein are methods for forming a chemical footer for a seawall comprising injecting a polymeric material to an injection depth from 1 foot to 3 feet below the mudline at each of a plurality of spaced locations along a landward side of a seawall. Additionally described herein are methods for reinforcing a seawall, comprising injecting a polymeric material to an injection depth at a plurality of spaced locations along the landward side of the seawall, wherein the injection depth is substantially at the vertical midpoint between the mudline and the top of the seawall.