Arrange clams in a large skillet; season with pepper. Spoon breadcrumbs onto clams and smooth with the back of spoon. Drizzle over olive oil. Transfer to broiler. Broil until breadcrumbs are lightly browned, 2 to 3 minutes.
Transfer skillet to stovetop over medium heat. Mix together lemon juice and 1/4 cup water; pour into bottom of skillet. Sprinkle over parsley. Cook 3 to 4 minutes. Serve immediately with lemon wedges.