"Tidal shoreline" means any land area within New Hampshire that is subject to the ebb and flow of the tide, extending from mean lower low water to land above the highest observable tide line. The term includes rocky shores, unconsolidated vegetated marine or estuarine banks, and artificial or constructed shorelines such as seawalls, bulkheads, and rip-rap slopes.
N.H. Admin. Code § Env-Wt 602.57