When Ocean Master activates his Tidal Wave trait would this replace printed hindering and printed blocking terrain with water terrain?

TIDAL WAVE: Once per game, give Ocean Master a double power action and choose an edge of the map your starting area is adjacent to. Roll 2d6 and double the result. Any squares within a number of squares away from the chosen edge are water terrain in addition to any other types this game.

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The wording seems to imply that other terrains (hindering, blocking and elevated) aren't replace, but just threated also as Water Terrain.