Dredging can cause erosion when you don't have a plan to stop the erosion. Unfortunately when issuing a permit a plan to stop erosion is not required. The same goes for a seawall, but a seawall is often the only solution when erosion gets out of hand.
The best way to prevent erosion is to plant as many palm trees on the beach as possible (as their roots hold the sand during for instance a hurricane), to keep vegetation like grass on the beach itself, don't remove the sea grass, don't dredge and don't remove the mangrove in front of the beach.
As this often conflicts with economic interests (including yours, Elbert), a compromise is often necessary, and I think a plan to prevent erosion should become mandatory.