PURPOSE: To maintain a water shielding property by covering a bentonite layer provided on a water front slope face and the top of an earth cover layer on the bentonite layer and placing a plurality of vegetation bass wherein vegetation soil implanted cylindrical parts are provided side by side.

CONSTITUTION: The upper end of a bentonite sheet 2 provided on a water front slope face is locked with an anchor 3 and fixed with a washer 5 mounted on an anchor pin 4 as well. Then, a cover earth layer 7 comprising cement- mixed soil dressing is sprayed on the sheet 2, thereby forming a water shielding layer. Then, vegetation bags 8 where cylindrical parts are arranged side by side in the crosswise direction are orientated in the horizontal direction and constructed on the cover earth layer 7 and fixed with the anchor pin 4. After a vegetation soil material 11 is stabilized, the bass 8 in the water front areas are bored, thereby growing thick the plants. This construction makes it possible to protect the bentonite layer and the cover earth layer and hold back slip off or erosion of rainwater and exert a water shielding performance for a long period.